src/amd/common/ac_llvm_build.c

/*
 * Copyright 2014 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 */
/* based on pieces from si_pipe.c and radeon_llvm_emit.c */
#include "ac_llvm_build.h"

#include <llvm-c/Core.h>

#include "c11/threads.h"

#include <assert.h>
#include <stdio.h>

#include "ac_llvm_util.h"
#include "ac_exp_param.h"
#include "util/bitscan.h"
#include "util/macros.h"
#include "util/u_atomic.h"
#include "util/u_math.h"
#include "sid.h"

#include "shader_enums.h"

#define AC_LLVM_INITIAL_CF_DEPTH 4

/* Data for if/else/endif and bgnloop/endloop control flow structures.
 */
struct ac_llvm_flow {
	/* Loop exit or next part of if/else/endif. */
	LLVMBasicBlockRef next_block;
	LLVMBasicBlockRef loop_entry_block;
};

/* Initialize module-independent parts of the context.
 *
 * The caller is responsible for initializing ctx::module and ctx::builder.
 */
void
ac_llvm_context_init(struct ac_llvm_context *ctx,
		     enum chip_class chip_class, enum radeon_family family)
{
	LLVMValueRef args[1];

	ctx->context = LLVMContextCreate();

	ctx->chip_class = chip_class;
	ctx->family = family;
	ctx->module = NULL;
	ctx->builder = NULL;

	ctx->voidt = LLVMVoidTypeInContext(ctx->context);
	ctx->i1 = LLVMInt1TypeInContext(ctx->context);
	ctx->i8 = LLVMInt8TypeInContext(ctx->context);
	ctx->i16 = LLVMIntTypeInContext(ctx->context, 16);
	ctx->i32 = LLVMIntTypeInContext(ctx->context, 32);
	ctx->i64 = LLVMIntTypeInContext(ctx->context, 64);
	ctx->intptr = ctx->i32;
	ctx->f16 = LLVMHalfTypeInContext(ctx->context);
	ctx->f32 = LLVMFloatTypeInContext(ctx->context);
	ctx->f64 = LLVMDoubleTypeInContext(ctx->context);
	ctx->v2i16 = LLVMVectorType(ctx->i16, 2);
	ctx->v2i32 = LLVMVectorType(ctx->i32, 2);
	ctx->v3i32 = LLVMVectorType(ctx->i32, 3);
	ctx->v4i32 = LLVMVectorType(ctx->i32, 4);
	ctx->v2f32 = LLVMVectorType(ctx->f32, 2);
	ctx->v4f32 = LLVMVectorType(ctx->f32, 4);
	ctx->v8i32 = LLVMVectorType(ctx->i32, 8);

	ctx->i16_0 = LLVMConstInt(ctx->i16, 0, false);
	ctx->i16_1 = LLVMConstInt(ctx->i16, 1, false);
	ctx->i32_0 = LLVMConstInt(ctx->i32, 0, false);
	ctx->i32_1 = LLVMConstInt(ctx->i32, 1, false);
	ctx->i64_0 = LLVMConstInt(ctx->i64, 0, false);
	ctx->i64_1 = LLVMConstInt(ctx->i64, 1, false);
	ctx->f32_0 = LLVMConstReal(ctx->f32, 0.0);
	ctx->f32_1 = LLVMConstReal(ctx->f32, 1.0);
	ctx->f64_0 = LLVMConstReal(ctx->f64, 0.0);
	ctx->f64_1 = LLVMConstReal(ctx->f64, 1.0);

	ctx->i1false = LLVMConstInt(ctx->i1, 0, false);
	ctx->i1true = LLVMConstInt(ctx->i1, 1, false);

	ctx->range_md_kind = LLVMGetMDKindIDInContext(ctx->context,
						     "range", 5);

	ctx->invariant_load_md_kind = LLVMGetMDKindIDInContext(ctx->context,
							       "invariant.load", 14);

	ctx->fpmath_md_kind = LLVMGetMDKindIDInContext(ctx->context, "fpmath", 6);

	args[0] = LLVMConstReal(ctx->f32, 2.5);
	ctx->fpmath_md_2p5_ulp = LLVMMDNodeInContext(ctx->context, args, 1);

	ctx->uniform_md_kind = LLVMGetMDKindIDInContext(ctx->context,
							"amdgpu.uniform", 14);

	ctx->empty_md = LLVMMDNodeInContext(ctx->context, NULL, 0);
}

void
ac_llvm_context_dispose(struct ac_llvm_context *ctx)
{
	free(ctx->flow);
	ctx->flow = NULL;
	ctx->flow_depth_max = 0;
}

int
ac_get_llvm_num_components(LLVMValueRef value)
{
	LLVMTypeRef type = LLVMTypeOf(value);
	unsigned num_components = LLVMGetTypeKind(type) == LLVMVectorTypeKind
	                              ? LLVMGetVectorSize(type)
	                              : 1;
	return num_components;
}

LLVMValueRef
ac_llvm_extract_elem(struct ac_llvm_context *ac,
		     LLVMValueRef value,
		     int index)
{
	if (LLVMGetTypeKind(LLVMTypeOf(value)) != LLVMVectorTypeKind) {
		assert(index == 0);
		return value;
	}

	return LLVMBuildExtractElement(ac->builder, value,
				       LLVMConstInt(ac->i32, index, false), "");
}

int
ac_get_elem_bits(struct ac_llvm_context *ctx, LLVMTypeRef type)
{
	if (LLVMGetTypeKind(type) == LLVMVectorTypeKind)
		type = LLVMGetElementType(type);

	if (LLVMGetTypeKind(type) == LLVMIntegerTypeKind)
		return LLVMGetIntTypeWidth(type);

	if (type == ctx->f16)
		return 16;
	if (type == ctx->f32)
		return 32;
	if (type == ctx->f64)
		return 64;

	unreachable("Unhandled type kind in get_elem_bits");
}

unsigned
ac_get_type_size(LLVMTypeRef type)
{
	LLVMTypeKind kind = LLVMGetTypeKind(type);

	switch (kind) {
	case LLVMIntegerTypeKind:
		return LLVMGetIntTypeWidth(type) / 8;
	case LLVMHalfTypeKind:
		return 2;
	case LLVMFloatTypeKind:
		return 4;
	case LLVMDoubleTypeKind:
		return 8;
	case LLVMPointerTypeKind:
		if (LLVMGetPointerAddressSpace(type) == AC_ADDR_SPACE_CONST_32BIT)
			return 4;
		return 8;
	case LLVMVectorTypeKind:
		return LLVMGetVectorSize(type) *
		       ac_get_type_size(LLVMGetElementType(type));
	case LLVMArrayTypeKind:
		return LLVMGetArrayLength(type) *
		       ac_get_type_size(LLVMGetElementType(type));
	default:
		assert(0);
		return 0;
	}
}

static LLVMTypeRef to_integer_type_scalar(struct ac_llvm_context *ctx, LLVMTypeRef t)
{
	if (t == ctx->f16 || t == ctx->i16)
		return ctx->i16;
	else if (t == ctx->f32 || t == ctx->i32)
		return ctx->i32;
	else if (t == ctx->f64 || t == ctx->i64)
		return ctx->i64;
	else
		unreachable("Unhandled integer size");
}

LLVMTypeRef
ac_to_integer_type(struct ac_llvm_context *ctx, LLVMTypeRef t)
{
	if (LLVMGetTypeKind(t) == LLVMVectorTypeKind) {
		LLVMTypeRef elem_type = LLVMGetElementType(t);
		return LLVMVectorType(to_integer_type_scalar(ctx, elem_type),
		                      LLVMGetVectorSize(t));
	}
	if (LLVMGetTypeKind(t) == LLVMPointerTypeKind) {
		switch (LLVMGetPointerAddressSpace(t)) {
		case AC_ADDR_SPACE_GLOBAL:
			return ctx->i64;
		case AC_ADDR_SPACE_LDS:
			return ctx->i32;
		default:
			unreachable("unhandled address space");
		}
	}
	return to_integer_type_scalar(ctx, t);
}

LLVMValueRef
ac_to_integer(struct ac_llvm_context *ctx, LLVMValueRef v)
{
	LLVMTypeRef type = LLVMTypeOf(v);
	if (LLVMGetTypeKind(type) == LLVMPointerTypeKind) {
		return LLVMBuildPtrToInt(ctx->builder, v, ac_to_integer_type(ctx, type), "");
	}
	return LLVMBuildBitCast(ctx->builder, v, ac_to_integer_type(ctx, type), "");
}

LLVMValueRef
ac_to_integer_or_pointer(struct ac_llvm_context *ctx, LLVMValueRef v)
{
	LLVMTypeRef type = LLVMTypeOf(v);
	if (LLVMGetTypeKind(type) == LLVMPointerTypeKind)
		return v;
	return ac_to_integer(ctx, v);
}

static LLVMTypeRef to_float_type_scalar(struct ac_llvm_context *ctx, LLVMTypeRef t)
{
	if (t == ctx->i16 || t == ctx->f16)
		return ctx->f16;
	else if (t == ctx->i32 || t == ctx->f32)
		return ctx->f32;
	else if (t == ctx->i64 || t == ctx->f64)
		return ctx->f64;
	else
		unreachable("Unhandled float size");
}

LLVMTypeRef
ac_to_float_type(struct ac_llvm_context *ctx, LLVMTypeRef t)
{
	if (LLVMGetTypeKind(t) == LLVMVectorTypeKind) {
		LLVMTypeRef elem_type = LLVMGetElementType(t);
		return LLVMVectorType(to_float_type_scalar(ctx, elem_type),
		                      LLVMGetVectorSize(t));
	}
	return to_float_type_scalar(ctx, t);
}

LLVMValueRef
ac_to_float(struct ac_llvm_context *ctx, LLVMValueRef v)
{
	LLVMTypeRef type = LLVMTypeOf(v);
	return LLVMBuildBitCast(ctx->builder, v, ac_to_float_type(ctx, type), "");
}


LLVMValueRef
ac_build_intrinsic(struct ac_llvm_context *ctx, const char *name,
		   LLVMTypeRef return_type, LLVMValueRef *params,
		   unsigned param_count, unsigned attrib_mask)
{
	LLVMValueRef function, call;
	bool set_callsite_attrs = !(attrib_mask & AC_FUNC_ATTR_LEGACY);

	function = LLVMGetNamedFunction(ctx->module, name);
	if (!function) {
		LLVMTypeRef param_types[32], function_type;
		unsigned i;

		assert(param_count <= 32);

		for (i = 0; i < param_count; ++i) {
			assert(params[i]);
			param_types[i] = LLVMTypeOf(params[i]);
		}
		function_type =
		    LLVMFunctionType(return_type, param_types, param_count, 0);
		function = LLVMAddFunction(ctx->module, name, function_type);

		LLVMSetFunctionCallConv(function, LLVMCCallConv);
		LLVMSetLinkage(function, LLVMExternalLinkage);

		if (!set_callsite_attrs)
			ac_add_func_attributes(ctx->context, function, attrib_mask);
	}

	call = LLVMBuildCall(ctx->builder, function, params, param_count, "");
	if (set_callsite_attrs)
		ac_add_func_attributes(ctx->context, call, attrib_mask);
	return call;
}

/**
 * Given the i32 or vNi32 \p type, generate the textual name (e.g. for use with
 * intrinsic names).
 */
void ac_build_type_name_for_intr(LLVMTypeRef type, char *buf, unsigned bufsize)
{
	LLVMTypeRef elem_type = type;

	assert(bufsize >= 8);

	if (LLVMGetTypeKind(type) == LLVMVectorTypeKind) {
		int ret = snprintf(buf, bufsize, "v%u",
					LLVMGetVectorSize(type));
		if (ret < 0) {
			char *type_name = LLVMPrintTypeToString(type);
			fprintf(stderr, "Error building type name for: %s\n",
				type_name);
			return;
		}
		elem_type = LLVMGetElementType(type);
		buf += ret;
		bufsize -= ret;
	}
	switch (LLVMGetTypeKind(elem_type)) {
	default: break;
	case LLVMIntegerTypeKind:
		snprintf(buf, bufsize, "i%d", LLVMGetIntTypeWidth(elem_type));
		break;
	case LLVMHalfTypeKind:
		snprintf(buf, bufsize, "f16");
		break;
	case LLVMFloatTypeKind:
		snprintf(buf, bufsize, "f32");
		break;
	case LLVMDoubleTypeKind:
		snprintf(buf, bufsize, "f64");
		break;
	}
}

/**
 * Helper function that builds an LLVM IR PHI node and immediately adds
 * incoming edges.
 */
LLVMValueRef
ac_build_phi(struct ac_llvm_context *ctx, LLVMTypeRef type,
	     unsigned count_incoming, LLVMValueRef *values,
	     LLVMBasicBlockRef *blocks)
{
	LLVMValueRef phi = LLVMBuildPhi(ctx->builder, type, "");
	LLVMAddIncoming(phi, values, blocks, count_incoming);
	return phi;
}

void ac_build_s_barrier(struct ac_llvm_context *ctx)
{
	ac_build_intrinsic(ctx, "llvm.amdgcn.s.barrier", ctx->voidt, NULL,
			   0, AC_FUNC_ATTR_CONVERGENT);
}

/* Prevent optimizations (at least of memory accesses) across the current
 * point in the program by emitting empty inline assembly that is marked as
 * having side effects.
 *
 * Optionally, a value can be passed through the inline assembly to prevent
 * LLVM from hoisting calls to ReadNone functions.
 */
void
ac_build_optimization_barrier(struct ac_llvm_context *ctx,
			      LLVMValueRef *pvgpr)
{
	static int counter = 0;

	LLVMBuilderRef builder = ctx->builder;
	char code[16];

	snprintf(code, sizeof(code), "; %d", p_atomic_inc_return(&counter));

	if (!pvgpr) {
		LLVMTypeRef ftype = LLVMFunctionType(ctx->voidt, NULL, 0, false);
		LLVMValueRef inlineasm = LLVMConstInlineAsm(ftype, code, "", true, false);
		LLVMBuildCall(builder, inlineasm, NULL, 0, "");
	} else {
		LLVMTypeRef ftype = LLVMFunctionType(ctx->i32, &ctx->i32, 1, false);
		LLVMValueRef inlineasm = LLVMConstInlineAsm(ftype, code, "=v,0", true, false);
		LLVMValueRef vgpr = *pvgpr;
		LLVMTypeRef vgpr_type = LLVMTypeOf(vgpr);
		unsigned vgpr_size = ac_get_type_size(vgpr_type);
		LLVMValueRef vgpr0;

		assert(vgpr_size % 4 == 0);

		vgpr = LLVMBuildBitCast(builder, vgpr, LLVMVectorType(ctx->i32, vgpr_size / 4), "");
		vgpr0 = LLVMBuildExtractElement(builder, vgpr, ctx->i32_0, "");
		vgpr0 = LLVMBuildCall(builder, inlineasm, &vgpr0, 1, "");
		vgpr = LLVMBuildInsertElement(builder, vgpr, vgpr0, ctx->i32_0, "");
		vgpr = LLVMBuildBitCast(builder, vgpr, vgpr_type, "");

		*pvgpr = vgpr;
	}
}

LLVMValueRef
ac_build_shader_clock(struct ac_llvm_context *ctx)
{
	LLVMValueRef tmp = ac_build_intrinsic(ctx, "llvm.readcyclecounter",
					      ctx->i64, NULL, 0, 0);
	return LLVMBuildBitCast(ctx->builder, tmp, ctx->v2i32, "");
}

LLVMValueRef
ac_build_ballot(struct ac_llvm_context *ctx,
		LLVMValueRef value)
{
	LLVMValueRef args[3] = {
		value,
		ctx->i32_0,
		LLVMConstInt(ctx->i32, LLVMIntNE, 0)
	};

	/* We currently have no other way to prevent LLVM from lifting the icmp
	 * calls to a dominating basic block.
	 */
	ac_build_optimization_barrier(ctx, &args[0]);

	args[0] = ac_to_integer(ctx, args[0]);

	return ac_build_intrinsic(ctx,
				  "llvm.amdgcn.icmp.i32",
				  ctx->i64, args, 3,
				  AC_FUNC_ATTR_NOUNWIND |
				  AC_FUNC_ATTR_READNONE |
				  AC_FUNC_ATTR_CONVERGENT);
}

LLVMValueRef
ac_build_vote_all(struct ac_llvm_context *ctx, LLVMValueRef value)
{
	LLVMValueRef active_set = ac_build_ballot(ctx, ctx->i32_1);
	LLVMValueRef vote_set = ac_build_ballot(ctx, value);
	return LLVMBuildICmp(ctx->builder, LLVMIntEQ, vote_set, active_set, "");
}

LLVMValueRef
ac_build_vote_any(struct ac_llvm_context *ctx, LLVMValueRef value)
{
	LLVMValueRef vote_set = ac_build_ballot(ctx, value);
	return LLVMBuildICmp(ctx->builder, LLVMIntNE, vote_set,
			     LLVMConstInt(ctx->i64, 0, 0), "");
}

LLVMValueRef
ac_build_vote_eq(struct ac_llvm_context *ctx, LLVMValueRef value)
{
	LLVMValueRef active_set = ac_build_ballot(ctx, ctx->i32_1);
	LLVMValueRef vote_set = ac_build_ballot(ctx, value);

	LLVMValueRef all = LLVMBuildICmp(ctx->builder, LLVMIntEQ,
					 vote_set, active_set, "");
	LLVMValueRef none = LLVMBuildICmp(ctx->builder, LLVMIntEQ,
					  vote_set,
					  LLVMConstInt(ctx->i64, 0, 0), "");
	return LLVMBuildOr(ctx->builder, all, none, "");
}

LLVMValueRef
ac_build_varying_gather_values(struct ac_llvm_context *ctx, LLVMValueRef *values,
			       unsigned value_count, unsigned component)
{
	LLVMValueRef vec = NULL;

	if (value_count == 1) {
		return values[component];
	} else if (!value_count)
		unreachable("value_count is 0");

	for (unsigned i = component; i < value_count + component; i++) {
		LLVMValueRef value = values[i];

		if (i == component)
			vec = LLVMGetUndef( LLVMVectorType(LLVMTypeOf(value), value_count));
		LLVMValueRef index = LLVMConstInt(ctx->i32, i - component, false);
		vec = LLVMBuildInsertElement(ctx->builder, vec, value, index, "");
	}
	return vec;
}

LLVMValueRef
ac_build_gather_values_extended(struct ac_llvm_context *ctx,
				LLVMValueRef *values,
				unsigned value_count,
				unsigned value_stride,
				bool load,
				bool always_vector)
{
	LLVMBuilderRef builder = ctx->builder;
	LLVMValueRef vec = NULL;
	unsigned i;

	if (value_count == 1 && !always_vector) {
		if (load)
			return LLVMBuildLoad(builder, values[0], "");
		return values[0];
	} else if (!value_count)
		unreachable("value_count is 0");

	for (i = 0; i < value_count; i++) {
		LLVMValueRef value = values[i * value_stride];
		if (load)
			value = LLVMBuildLoad(builder, value, "");

		if (!i)
			vec = LLVMGetUndef( LLVMVectorType(LLVMTypeOf(value), value_count));
		LLVMValueRef index = LLVMConstInt(ctx->i32, i, false);
		vec = LLVMBuildInsertElement(builder, vec, value, index, "");
	}
	return vec;
}

LLVMValueRef
ac_build_gather_values(struct ac_llvm_context *ctx,
		       LLVMValueRef *values,
		       unsigned value_count)
{
	return ac_build_gather_values_extended(ctx, values, value_count, 1, false, false);
}

/* Expand a scalar or vector to <dst_channels x type> by filling the remaining
 * channels with undef. Extract at most src_channels components from the input.
 */
static LLVMValueRef
ac_build_expand(struct ac_llvm_context *ctx,
		LLVMValueRef value,
		unsigned src_channels,
		unsigned dst_channels)
{
	LLVMTypeRef elemtype;
	LLVMValueRef chan[dst_channels];

	if (LLVMGetTypeKind(LLVMTypeOf(value)) == LLVMVectorTypeKind) {
		unsigned vec_size = LLVMGetVectorSize(LLVMTypeOf(value));

		if (src_channels == dst_channels && vec_size == dst_channels)
			return value;

		src_channels = MIN2(src_channels, vec_size);

		for (unsigned i = 0; i < src_channels; i++)
			chan[i] = ac_llvm_extract_elem(ctx, value, i);

		elemtype = LLVMGetElementType(LLVMTypeOf(value));
	} else {
		if (src_channels) {
			assert(src_channels == 1);
			chan[0] = value;
		}
		elemtype = LLVMTypeOf(value);
	}

	for (unsigned i = src_channels; i < dst_channels; i++)
		chan[i] = LLVMGetUndef(elemtype);

	return ac_build_gather_values(ctx, chan, dst_channels);
}

/* Expand a scalar or vector to <4 x type> by filling the remaining channels
 * with undef. Extract at most num_channels components from the input.
 */
LLVMValueRef ac_build_expand_to_vec4(struct ac_llvm_context *ctx,
				     LLVMValueRef value,
				     unsigned num_channels)
{
	return ac_build_expand(ctx, value, num_channels, 4);
}

LLVMValueRef ac_build_round(struct ac_llvm_context *ctx, LLVMValueRef value)
{
	unsigned type_size = ac_get_type_size(LLVMTypeOf(value));
	const char *name;

	if (type_size == 2)
		name = "llvm.rint.f16";
	else if (type_size == 4)
		name = "llvm.rint.f32";
	else
		name = "llvm.rint.f64";

	return ac_build_intrinsic(ctx, name, LLVMTypeOf(value), &value, 1,
				  AC_FUNC_ATTR_READNONE);
}

LLVMValueRef
ac_build_fdiv(struct ac_llvm_context *ctx,
	      LLVMValueRef num,
	      LLVMValueRef den)
{
	/* If we do (num / den), LLVM >= 7.0 does:
	 *    return num * v_rcp_f32(den * (fabs(den) > 0x1.0p+96f ? 0x1.0p-32f : 1.0f));
	 *
	 * If we do (num * (1 / den)), LLVM does:
	 *    return num * v_rcp_f32(den);
	 */
	LLVMValueRef one = LLVMTypeOf(num) == ctx->f64 ? ctx->f64_1 : ctx->f32_1;
	LLVMValueRef rcp = LLVMBuildFDiv(ctx->builder, one, den, "");
	LLVMValueRef ret = LLVMBuildFMul(ctx->builder, num, rcp, "");

	/* Use v_rcp_f32 instead of precise division. */
	if (!LLVMIsConstant(ret))
		LLVMSetMetadata(ret, ctx->fpmath_md_kind, ctx->fpmath_md_2p5_ulp);
	return ret;
}

/* See fast_idiv_by_const.h. */
/* Set: increment = util_fast_udiv_info::increment ? multiplier : 0; */
LLVMValueRef ac_build_fast_udiv(struct ac_llvm_context *ctx,
				LLVMValueRef num,
				LLVMValueRef multiplier,
				LLVMValueRef pre_shift,
				LLVMValueRef post_shift,
				LLVMValueRef increment)
{
	LLVMBuilderRef builder = ctx->builder;

	num = LLVMBuildLShr(builder, num, pre_shift, "");
	num = LLVMBuildMul(builder,
			   LLVMBuildZExt(builder, num, ctx->i64, ""),
			   LLVMBuildZExt(builder, multiplier, ctx->i64, ""), "");
	num = LLVMBuildAdd(builder, num,
			   LLVMBuildZExt(builder, increment, ctx->i64, ""), "");
	num = LLVMBuildLShr(builder, num, LLVMConstInt(ctx->i64, 32, 0), "");
	num = LLVMBuildTrunc(builder, num, ctx->i32, "");
	return LLVMBuildLShr(builder, num, post_shift, "");
}

/* See fast_idiv_by_const.h. */
/* If num != UINT_MAX, this more efficient version can be used. */
/* Set: increment = util_fast_udiv_info::increment; */
LLVMValueRef ac_build_fast_udiv_nuw(struct ac_llvm_context *ctx,
				    LLVMValueRef num,
				    LLVMValueRef multiplier,
				    LLVMValueRef pre_shift,
				    LLVMValueRef post_shift,
				    LLVMValueRef increment)
{
	LLVMBuilderRef builder = ctx->builder;

	num = LLVMBuildLShr(builder, num, pre_shift, "");
	num = LLVMBuildNUWAdd(builder, num, increment, "");
	num = LLVMBuildMul(builder,
			   LLVMBuildZExt(builder, num, ctx->i64, ""),
			   LLVMBuildZExt(builder, multiplier, ctx->i64, ""), "");
	num = LLVMBuildLShr(builder, num, LLVMConstInt(ctx->i64, 32, 0), "");
	num = LLVMBuildTrunc(builder, num, ctx->i32, "");
	return LLVMBuildLShr(builder, num, post_shift, "");
}

/* See fast_idiv_by_const.h. */
/* Both operands must fit in 31 bits and the divisor must not be 1. */
LLVMValueRef ac_build_fast_udiv_u31_d_not_one(struct ac_llvm_context *ctx,
					      LLVMValueRef num,
					      LLVMValueRef multiplier,
					      LLVMValueRef post_shift)
{
	LLVMBuilderRef builder = ctx->builder;

	num = LLVMBuildMul(builder,
			   LLVMBuildZExt(builder, num, ctx->i64, ""),
			   LLVMBuildZExt(builder, multiplier, ctx->i64, ""), "");
	num = LLVMBuildLShr(builder, num, LLVMConstInt(ctx->i64, 32, 0), "");
	num = LLVMBuildTrunc(builder, num, ctx->i32, "");
	return LLVMBuildLShr(builder, num, post_shift, "");
}

/* Coordinates for cube map selection. sc, tc, and ma are as in Table 8.27
 * of the OpenGL 4.5 (Compatibility Profile) specification, except ma is
 * already multiplied by two. id is the cube face number.
 */
struct cube_selection_coords {
	LLVMValueRef stc[2];
	LLVMValueRef ma;
	LLVMValueRef id;
};

static void
build_cube_intrinsic(struct ac_llvm_context *ctx,
		     LLVMValueRef in[3],
		     struct cube_selection_coords *out)
{
	LLVMTypeRef f32 = ctx->f32;

	out->stc[1] = ac_build_intrinsic(ctx, "llvm.amdgcn.cubetc",
					 f32, in, 3, AC_FUNC_ATTR_READNONE);
	out->stc[0] = ac_build_intrinsic(ctx, "llvm.amdgcn.cubesc",
					 f32, in, 3, AC_FUNC_ATTR_READNONE);
	out->ma = ac_build_intrinsic(ctx, "llvm.amdgcn.cubema",
				     f32, in, 3, AC_FUNC_ATTR_READNONE);
	out->id = ac_build_intrinsic(ctx, "llvm.amdgcn.cubeid",
				     f32, in, 3, AC_FUNC_ATTR_READNONE);
}

/**
 * Build a manual selection sequence for cube face sc/tc coordinates and
 * major axis vector (multiplied by 2 for consistency) for the given
 * vec3 \p coords, for the face implied by \p selcoords.
 *
 * For the major axis, we always adjust the sign to be in the direction of
 * selcoords.ma; i.e., a positive out_ma means that coords is pointed towards
 * the selcoords major axis.
 */
static void build_cube_select(struct ac_llvm_context *ctx,
			      const struct cube_selection_coords *selcoords,
			      const LLVMValueRef *coords,
			      LLVMValueRef *out_st,
			      LLVMValueRef *out_ma)
{
	LLVMBuilderRef builder = ctx->builder;
	LLVMTypeRef f32 = LLVMTypeOf(coords[0]);
	LLVMValueRef is_ma_positive;
	LLVMValueRef sgn_ma;
	LLVMValueRef is_ma_z, is_not_ma_z;
	LLVMValueRef is_ma_y;
	LLVMValueRef is_ma_x;
	LLVMValueRef sgn;
	LLVMValueRef tmp;

	is_ma_positive = LLVMBuildFCmp(builder, LLVMRealUGE,
		selcoords->ma, LLVMConstReal(f32, 0.0), "");
	sgn_ma = LLVMBuildSelect(builder, is_ma_positive,
		LLVMConstReal(f32, 1.0), LLVMConstReal(f32, -1.0), "");

	is_ma_z = LLVMBuildFCmp(builder, LLVMRealUGE, selcoords->id, LLVMConstReal(f32, 4.0), "");
	is_not_ma_z = LLVMBuildNot(builder, is_ma_z, "");
	is_ma_y = LLVMBuildAnd(builder, is_not_ma_z,
		LLVMBuildFCmp(builder, LLVMRealUGE, selcoords->id, LLVMConstReal(f32, 2.0), ""), "");
	is_ma_x = LLVMBuildAnd(builder, is_not_ma_z, LLVMBuildNot(builder, is_ma_y, ""), "");

	/* Select sc */
	tmp = LLVMBuildSelect(builder, is_ma_x, coords[2], coords[0], "");
	sgn = LLVMBuildSelect(builder, is_ma_y, LLVMConstReal(f32, 1.0),
		LLVMBuildSelect(builder, is_ma_z, sgn_ma,
			LLVMBuildFNeg(builder, sgn_ma, ""), ""), "");
	out_st[0] = LLVMBuildFMul(builder, tmp, sgn, "");

	/* Select tc */
	tmp = LLVMBuildSelect(builder, is_ma_y, coords[2], coords[1], "");
	sgn = LLVMBuildSelect(builder, is_ma_y, sgn_ma,
		LLVMConstReal(f32, -1.0), "");
	out_st[1] = LLVMBuildFMul(builder, tmp, sgn, "");

	/* Select ma */
	tmp = LLVMBuildSelect(builder, is_ma_z, coords[2],
		LLVMBuildSelect(builder, is_ma_y, coords[1], coords[0], ""), "");
	tmp = ac_build_intrinsic(ctx, "llvm.fabs.f32",
				 ctx->f32, &tmp, 1, AC_FUNC_ATTR_READNONE);
	*out_ma = LLVMBuildFMul(builder, tmp, LLVMConstReal(f32, 2.0), "");
}

void
ac_prepare_cube_coords(struct ac_llvm_context *ctx,
		       bool is_deriv, bool is_array, bool is_lod,
		       LLVMValueRef *coords_arg,
		       LLVMValueRef *derivs_arg)
{

	LLVMBuilderRef builder = ctx->builder;
	struct cube_selection_coords selcoords;
	LLVMValueRef coords[3];
	LLVMValueRef invma;

	if (is_array && !is_lod) {
		LLVMValueRef tmp = ac_build_round(ctx, coords_arg[3]);

		/* Section 8.9 (Texture Functions) of the GLSL 4.50 spec says:
		 *
		 *    "For Array forms, the array layer used will be
		 *
		 *       max(0, min(d−1, floor(layer+0.5)))
		 *
		 *     where d is the depth of the texture array and layer
		 *     comes from the component indicated in the tables below.
		 *     Workaroudn for an issue where the layer is taken from a
		 *     helper invocation which happens to fall on a different
		 *     layer due to extrapolation."
		 *
		 * VI and earlier attempt to implement this in hardware by
		 * clamping the value of coords[2] = (8 * layer) + face.
		 * Unfortunately, this means that the we end up with the wrong
		 * face when clamping occurs.
		 *
		 * Clamp the layer earlier to work around the issue.
		 */
		if (ctx->chip_class <= VI) {
			LLVMValueRef ge0;
			ge0 = LLVMBuildFCmp(builder, LLVMRealOGE, tmp, ctx->f32_0, "");
			tmp = LLVMBuildSelect(builder, ge0, tmp, ctx->f32_0, "");
		}

		coords_arg[3] = tmp;
	}

	build_cube_intrinsic(ctx, coords_arg, &selcoords);

	invma = ac_build_intrinsic(ctx, "llvm.fabs.f32",
			ctx->f32, &selcoords.ma, 1, AC_FUNC_ATTR_READNONE);
	invma = ac_build_fdiv(ctx, LLVMConstReal(ctx->f32, 1.0), invma);

	for (int i = 0; i < 2; ++i)
		coords[i] = LLVMBuildFMul(builder, selcoords.stc[i], invma, "");

	coords[2] = selcoords.id;

	if (is_deriv && derivs_arg) {
		LLVMValueRef derivs[4];
		int axis;

		/* Convert cube derivatives to 2D derivatives. */
		for (axis = 0; axis < 2; axis++) {
			LLVMValueRef deriv_st[2];
			LLVMValueRef deriv_ma;

			/* Transform the derivative alongside the texture
			 * coordinate. Mathematically, the correct formula is
			 * as follows. Assume we're projecting onto the +Z face
			 * and denote by dx/dh the derivative of the (original)
			 * X texture coordinate with respect to horizontal
			 * window coordinates. The projection onto the +Z face
			 * plane is:
			 *
			 *   f(x,z) = x/z
			 *
			 * Then df/dh = df/dx * dx/dh + df/dz * dz/dh
			 *            = 1/z * dx/dh - x/z * 1/z * dz/dh.
			 *
			 * This motivatives the implementation below.
			 *
			 * Whether this actually gives the expected results for
			 * apps that might feed in derivatives obtained via
			 * finite differences is anyone's guess. The OpenGL spec
			 * seems awfully quiet about how textureGrad for cube
			 * maps should be handled.
			 */
			build_cube_select(ctx, &selcoords, &derivs_arg[axis * 3],
					  deriv_st, &deriv_ma);

			deriv_ma = LLVMBuildFMul(builder, deriv_ma, invma, "");

			for (int i = 0; i < 2; ++i)
				derivs[axis * 2 + i] =
					LLVMBuildFSub(builder,
						LLVMBuildFMul(builder, deriv_st[i], invma, ""),
						LLVMBuildFMul(builder, deriv_ma, coords[i], ""), "");
		}

		memcpy(derivs_arg, derivs, sizeof(derivs));
	}

	/* Shift the texture coordinate. This must be applied after the
	 * derivative calculation.
	 */
	for (int i = 0; i < 2; ++i)
		coords[i] = LLVMBuildFAdd(builder, coords[i], LLVMConstReal(ctx->f32, 1.5), "");

	if (is_array) {
		/* for cube arrays coord.z = coord.w(array_index) * 8 + face */
		/* coords_arg.w component - array_index for cube arrays */
		coords[2] = ac_build_fmad(ctx, coords_arg[3], LLVMConstReal(ctx->f32, 8.0), coords[2]);
	}

	memcpy(coords_arg, coords, sizeof(coords));
}


LLVMValueRef
ac_build_fs_interp(struct ac_llvm_context *ctx,
		   LLVMValueRef llvm_chan,
		   LLVMValueRef attr_number,
		   LLVMValueRef params,
		   LLVMValueRef i,
		   LLVMValueRef j)
{
	LLVMValueRef args[5];
	LLVMValueRef p1;

	args[0] = i;
	args[1] = llvm_chan;
	args[2] = attr_number;
	args[3] = params;

	p1 = ac_build_intrinsic(ctx, "llvm.amdgcn.interp.p1",
				ctx->f32, args, 4, AC_FUNC_ATTR_READNONE);

	args[0] = p1;
	args[1] = j;
	args[2] = llvm_chan;
	args[3] = attr_number;
	args[4] = params;

	return ac_build_intrinsic(ctx, "llvm.amdgcn.interp.p2",
				  ctx->f32, args, 5, AC_FUNC_ATTR_READNONE);
}

LLVMValueRef
ac_build_fs_interp_mov(struct ac_llvm_context *ctx,
		       LLVMValueRef parameter,
		       LLVMValueRef llvm_chan,
		       LLVMValueRef attr_number,
		       LLVMValueRef params)
{
	LLVMValueRef args[4];

	args[0] = parameter;
	args[1] = llvm_chan;
	args[2] = attr_number;
	args[3] = params;

	return ac_build_intrinsic(ctx, "llvm.amdgcn.interp.mov",
				  ctx->f32, args, 4, AC_FUNC_ATTR_READNONE);
}

LLVMValueRef
ac_build_gep_ptr(struct ac_llvm_context *ctx,
	         LLVMValueRef base_ptr,
	         LLVMValueRef index)
{
	return LLVMBuildGEP(ctx->builder, base_ptr, &index, 1, "");
}

LLVMValueRef
ac_build_gep0(struct ac_llvm_context *ctx,
	      LLVMValueRef base_ptr,
	      LLVMValueRef index)
{
	LLVMValueRef indices[2] = {
		ctx->i32_0,
		index,
	};
	return LLVMBuildGEP(ctx->builder, base_ptr, indices, 2, "");
}

LLVMValueRef ac_build_pointer_add(struct ac_llvm_context *ctx, LLVMValueRef ptr,
				  LLVMValueRef index)
{
	return LLVMBuildPointerCast(ctx->builder,
				    ac_build_gep0(ctx, ptr, index),
				    LLVMTypeOf(ptr), "");
}

void
ac_build_indexed_store(struct ac_llvm_context *ctx,
		       LLVMValueRef base_ptr, LLVMValueRef index,
		       LLVMValueRef value)
{
	LLVMBuildStore(ctx->builder, value,
		       ac_build_gep0(ctx, base_ptr, index));
}

/**
 * Build an LLVM bytecode indexed load using LLVMBuildGEP + LLVMBuildLoad.
 * It's equivalent to doing a load from &base_ptr[index].
 *
 * \param base_ptr  Where the array starts.
 * \param index     The element index into the array.
 * \param uniform   Whether the base_ptr and index can be assumed to be
 *                  dynamically uniform (i.e. load to an SGPR)
 * \param invariant Whether the load is invariant (no other opcodes affect it)
 * \param no_unsigned_wraparound
 *    For all possible re-associations and re-distributions of an expression
 *    "base_ptr + index * elemsize" into "addr + offset" (excluding GEPs
 *    without inbounds in base_ptr), this parameter is true if "addr + offset"
 *    does not result in an unsigned integer wraparound. This is used for
 *    optimal code generation of 32-bit pointer arithmetic.
 *
 *    For example, a 32-bit immediate offset that causes a 32-bit unsigned
 *    integer wraparound can't be an imm offset in s_load_dword, because
 *    the instruction performs "addr + offset" in 64 bits.
 *
 *    Expected usage for bindless textures by chaining GEPs:
 *      // possible unsigned wraparound, don't use InBounds:
 *      ptr1 = LLVMBuildGEP(base_ptr, index);
 *      image = load(ptr1); // becomes "s_load ptr1, 0"
 *
 *      ptr2 = LLVMBuildInBoundsGEP(ptr1, 32 / elemsize);
 *      sampler = load(ptr2); // becomes "s_load ptr1, 32" thanks to InBounds
 */
static LLVMValueRef
ac_build_load_custom(struct ac_llvm_context *ctx, LLVMValueRef base_ptr,
		     LLVMValueRef index, bool uniform, bool invariant,
		     bool no_unsigned_wraparound)
{
	LLVMValueRef pointer, result;
	LLVMValueRef indices[2] = {ctx->i32_0, index};

	if (no_unsigned_wraparound &&
	    LLVMGetPointerAddressSpace(LLVMTypeOf(base_ptr)) == AC_ADDR_SPACE_CONST_32BIT)
		pointer = LLVMBuildInBoundsGEP(ctx->builder, base_ptr, indices, 2, "");
	else
		pointer = LLVMBuildGEP(ctx->builder, base_ptr, indices, 2, "");

	if (uniform)
		LLVMSetMetadata(pointer, ctx->uniform_md_kind, ctx->empty_md);
	result = LLVMBuildLoad(ctx->builder, pointer, "");
	if (invariant)
		LLVMSetMetadata(result, ctx->invariant_load_md_kind, ctx->empty_md);
	return result;
}

LLVMValueRef ac_build_load(struct ac_llvm_context *ctx, LLVMValueRef base_ptr,
			   LLVMValueRef index)
{
	return ac_build_load_custom(ctx, base_ptr, index, false, false, false);
}

LLVMValueRef ac_build_load_invariant(struct ac_llvm_context *ctx,
				     LLVMValueRef base_ptr, LLVMValueRef index)
{
	return ac_build_load_custom(ctx, base_ptr, index, false, true, false);
}

/* This assumes that there is no unsigned integer wraparound during the address
 * computation, excluding all GEPs within base_ptr. */
LLVMValueRef ac_build_load_to_sgpr(struct ac_llvm_context *ctx,
				   LLVMValueRef base_ptr, LLVMValueRef index)
{
	return ac_build_load_custom(ctx, base_ptr, index, true, true, true);
}

/* See ac_build_load_custom() documentation. */
LLVMValueRef ac_build_load_to_sgpr_uint_wraparound(struct ac_llvm_context *ctx,
				   LLVMValueRef base_ptr, LLVMValueRef index)
{
	return ac_build_load_custom(ctx, base_ptr, index, true, true, false);
}

/* TBUFFER_STORE_FORMAT_{X,XY,XYZ,XYZW} <- the suffix is selected by num_channels=1..4.
 * The type of vdata must be one of i32 (num_channels=1), v2i32 (num_channels=2),
 * or v4i32 (num_channels=3,4).
 */
void
ac_build_buffer_store_dword(struct ac_llvm_context *ctx,
			    LLVMValueRef rsrc,
			    LLVMValueRef vdata,
			    unsigned num_channels,
			    LLVMValueRef voffset,
			    LLVMValueRef soffset,
			    unsigned inst_offset,
			    bool glc,
			    bool slc,
			    bool writeonly_memory,
			    bool swizzle_enable_hint)
{
	/* Split 3 channel stores, becase LLVM doesn't support 3-channel
	 * intrinsics. */
	if (num_channels == 3) {
		LLVMValueRef v[3], v01;

		for (int i = 0; i < 3; i++) {
			v[i] = LLVMBuildExtractElement(ctx->builder, vdata,
					LLVMConstInt(ctx->i32, i, 0), "");
		}
		v01 = ac_build_gather_values(ctx, v, 2);

		ac_build_buffer_store_dword(ctx, rsrc, v01, 2, voffset,
					    soffset, inst_offset, glc, slc,
					    writeonly_memory, swizzle_enable_hint);
		ac_build_buffer_store_dword(ctx, rsrc, v[2], 1, voffset,
					    soffset, inst_offset + 8,
					    glc, slc,
					    writeonly_memory, swizzle_enable_hint);
		return;
	}

	/* SWIZZLE_ENABLE requires that soffset isn't folded into voffset
	 * (voffset is swizzled, but soffset isn't swizzled).
	 * llvm.amdgcn.buffer.store doesn't have a separate soffset parameter.
	 */
	if (!swizzle_enable_hint) {
		LLVMValueRef offset = soffset;

		static const char *types[] = {"f32", "v2f32", "v4f32"};

		if (inst_offset)
			offset = LLVMBuildAdd(ctx->builder, offset,
					      LLVMConstInt(ctx->i32, inst_offset, 0), "");
		if (voffset)
			offset = LLVMBuildAdd(ctx->builder, offset, voffset, "");

		LLVMValueRef args[] = {
			ac_to_float(ctx, vdata),
			LLVMBuildBitCast(ctx->builder, rsrc, ctx->v4i32, ""),
			ctx->i32_0,
			offset,
			LLVMConstInt(ctx->i1, glc, 0),
			LLVMConstInt(ctx->i1, slc, 0),
		};

		char name[256];
		snprintf(name, sizeof(name), "llvm.amdgcn.buffer.store.%s",
			 types[CLAMP(num_channels, 1, 3) - 1]);

		ac_build_intrinsic(ctx, name, ctx->voidt,
				   args, ARRAY_SIZE(args),
				   writeonly_memory ?
				   AC_FUNC_ATTR_INACCESSIBLE_MEM_ONLY :
				   AC_FUNC_ATTR_WRITEONLY);
		return;
	}

	static const unsigned dfmt[] = {
		V_008F0C_BUF_DATA_FORMAT_32,
		V_008F0C_BUF_DATA_FORMAT_32_32,
		V_008F0C_BUF_DATA_FORMAT_32_32_32,
		V_008F0C_BUF_DATA_FORMAT_32_32_32_32
	};
	static const char *types[] = {"i32", "v2i32", "v4i32"};
	LLVMValueRef args[] = {
		vdata,
		LLVMBuildBitCast(ctx->builder, rsrc, ctx->v4i32, ""),
		ctx->i32_0,
		voffset ? voffset : ctx->i32_0,
		soffset,
		LLVMConstInt(ctx->i32, inst_offset, 0),
		LLVMConstInt(ctx->i32, dfmt[num_channels - 1], 0),
		LLVMConstInt(ctx->i32, V_008F0C_BUF_NUM_FORMAT_UINT, 0),
		LLVMConstInt(ctx->i1, glc, 0),
		LLVMConstInt(ctx->i1, slc, 0),
	};
	char name[256];
	snprintf(name, sizeof(name), "llvm.amdgcn.tbuffer.store.%s",
		 types[CLAMP(num_channels, 1, 3) - 1]);

	ac_build_intrinsic(ctx, name, ctx->voidt,
			   args, ARRAY_SIZE(args),
			   writeonly_memory ?
				   AC_FUNC_ATTR_INACCESSIBLE_MEM_ONLY :
				   AC_FUNC_ATTR_WRITEONLY);
}

static LLVMValueRef
ac_build_buffer_load_common(struct ac_llvm_context *ctx,
			    LLVMValueRef rsrc,
			    LLVMValueRef vindex,
			    LLVMValueRef voffset,
			    unsigned num_channels,
			    bool glc,
			    bool slc,
			    bool can_speculate,
			    bool use_format)
{
	LLVMValueRef args[] = {
		LLVMBuildBitCast(ctx->builder, rsrc, ctx->v4i32, ""),
		vindex ? vindex : ctx->i32_0,
		voffset,
		LLVMConstInt(ctx->i1, glc, 0),
		LLVMConstInt(ctx->i1, slc, 0)
	};
	unsigned func = CLAMP(num_channels, 1, 3) - 1;

	LLVMTypeRef types[] = {ctx->f32, ctx->v2f32, ctx->v4f32};
	const char *type_names[] = {"f32", "v2f32", "v4f32"};
	char name[256];

	if (use_format) {
		snprintf(name, sizeof(name), "llvm.amdgcn.buffer.load.format.%s",
			 type_names[func]);
	} else {
		snprintf(name, sizeof(name), "llvm.amdgcn.buffer.load.%s",
			 type_names[func]);
	}

	return ac_build_intrinsic(ctx, name, types[func], args,
				  ARRAY_SIZE(args),
				  ac_get_load_intr_attribs(can_speculate));
}

static LLVMValueRef
ac_build_llvm8_buffer_load_common(struct ac_llvm_context *ctx,
				  LLVMValueRef rsrc,
				  LLVMValueRef vindex,
				  LLVMValueRef voffset,
				  LLVMValueRef soffset,
				  unsigned num_channels,
				  bool glc,
				  bool slc,
				  bool can_speculate,
				  bool use_format,
				  bool structurized)
{
	LLVMValueRef args[5];
	int idx = 0;
	args[idx++] = LLVMBuildBitCast(ctx->builder, rsrc, ctx->v4i32, "");
	if (structurized)
		args[idx++] = vindex ? vindex : ctx->i32_0;
	args[idx++] = voffset ? voffset : ctx->i32_0;
	args[idx++] = soffset ? soffset : ctx->i32_0;
	args[idx++] = LLVMConstInt(ctx->i32, (glc ? 1 : 0) + (slc ? 2 : 0), 0);
	unsigned func = CLAMP(num_channels, 1, 3) - 1;

	LLVMTypeRef types[] = {ctx->f32, ctx->v2f32, ctx->v4f32};
	const char *type_names[] = {"f32", "v2f32", "v4f32"};
	const char *indexing_kind = structurized ? "struct" : "raw";
	char name[256];

	if (use_format) {
		snprintf(name, sizeof(name), "llvm.amdgcn.%s.buffer.load.format.%s",
			 indexing_kind, type_names[func]);
	} else {
		snprintf(name, sizeof(name), "llvm.amdgcn.%s.buffer.load.%s",
			 indexing_kind, type_names[func]);
	}

	return ac_build_intrinsic(ctx, name, types[func], args,
				  idx,
				  ac_get_load_intr_attribs(can_speculate));
}

LLVMValueRef
ac_build_buffer_load(struct ac_llvm_context *ctx,
		     LLVMValueRef rsrc,
		     int num_channels,
		     LLVMValueRef vindex,
		     LLVMValueRef voffset,
		     LLVMValueRef soffset,
		     unsigned inst_offset,
		     unsigned glc,
		     unsigned slc,
		     bool can_speculate,
		     bool allow_smem)
{
	LLVMValueRef offset = LLVMConstInt(ctx->i32, inst_offset, 0);
	if (voffset)
		offset = LLVMBuildAdd(ctx->builder, offset, voffset, "");
	if (soffset)
		offset = LLVMBuildAdd(ctx->builder, offset, soffset, "");

	if (allow_smem && !slc &&
	    (!glc || (HAVE_LLVM >= 0x0800 && ctx->chip_class >= VI))) {
		assert(vindex == NULL);

		LLVMValueRef result[8];

		for (int i = 0; i < num_channels; i++) {
			if (i) {
				offset = LLVMBuildAdd(ctx->builder, offset,
						      LLVMConstInt(ctx->i32, 4, 0), "");
			}
			const char *intrname =
				HAVE_LLVM >= 0x0800 ? "llvm.amdgcn.s.buffer.load.f32"
						    : "llvm.SI.load.const.v4i32";
			unsigned num_args = HAVE_LLVM >= 0x0800 ? 3 : 2;
			LLVMValueRef args[3] = {
				rsrc,
				offset,
				glc ? ctx->i32_1 : ctx->i32_0,
			};
			result[i] = ac_build_intrinsic(ctx, intrname,
						       ctx->f32, args, num_args,
						       AC_FUNC_ATTR_READNONE |
						       (HAVE_LLVM < 0x0800 ? AC_FUNC_ATTR_LEGACY : 0));
		}
		if (num_channels == 1)
			return result[0];

		if (num_channels == 3)
			result[num_channels++] = LLVMGetUndef(ctx->f32);
		return ac_build_gather_values(ctx, result, num_channels);
	}

	return ac_build_buffer_load_common(ctx, rsrc, vindex, offset,
					   num_channels, glc, slc,
					   can_speculate, false);
}

LLVMValueRef ac_build_buffer_load_format(struct ac_llvm_context *ctx,
					 LLVMValueRef rsrc,
					 LLVMValueRef vindex,
					 LLVMValueRef voffset,
					 unsigned num_channels,
					 bool glc,
					 bool can_speculate)
{
	if (HAVE_LLVM >= 0x800) {
		return ac_build_llvm8_buffer_load_common(ctx, rsrc, vindex, voffset, ctx->i32_0,
							 num_channels, glc, false,
							 can_speculate, true, true);
	}
	return ac_build_buffer_load_common(ctx, rsrc, vindex, voffset,
					   num_channels, glc, false,
					   can_speculate, true);
}

LLVMValueRef ac_build_buffer_load_format_gfx9_safe(struct ac_llvm_context *ctx,
                                                  LLVMValueRef rsrc,
                                                  LLVMValueRef vindex,
                                                  LLVMValueRef voffset,
                                                  unsigned num_channels,
                                                  bool glc,
                                                  bool can_speculate)
{
	if (HAVE_LLVM >= 0x800) {
		return ac_build_llvm8_buffer_load_common(ctx, rsrc, vindex, voffset, ctx->i32_0,
							 num_channels, glc, false,
							 can_speculate, true, true);
	}

	LLVMValueRef elem_count = LLVMBuildExtractElement(ctx->builder, rsrc, LLVMConstInt(ctx->i32, 2, 0), "");
	LLVMValueRef stride = LLVMBuildExtractElement(ctx->builder, rsrc, ctx->i32_1, "");
	stride = LLVMBuildLShr(ctx->builder, stride, LLVMConstInt(ctx->i32, 16, 0), "");

	LLVMValueRef new_elem_count = LLVMBuildSelect(ctx->builder,
	                                              LLVMBuildICmp(ctx->builder, LLVMIntUGT, elem_count, stride, ""),
	                                              elem_count, stride, "");

	LLVMValueRef new_rsrc = LLVMBuildInsertElement(ctx->builder, rsrc, new_elem_count,
	                                               LLVMConstInt(ctx->i32, 2, 0), "");

	return ac_build_buffer_load_common(ctx, new_rsrc, vindex, voffset,
	                                   num_channels, glc, false,
	                                   can_speculate, true);
}

LLVMValueRef
ac_build_tbuffer_load_short(struct ac_llvm_context *ctx,
			    LLVMValueRef rsrc,
			    LLVMValueRef vindex,
			    LLVMValueRef voffset,
				LLVMValueRef soffset,
				LLVMValueRef immoffset,
				LLVMValueRef glc)
{
	unsigned dfmt = V_008F0C_BUF_DATA_FORMAT_16;
	unsigned nfmt = V_008F0C_BUF_NUM_FORMAT_UINT;
	LLVMValueRef res;

	if (HAVE_LLVM >= 0x0800) {
		voffset = LLVMBuildAdd(ctx->builder, voffset, immoffset, "");

		res = ac_build_llvm8_tbuffer_load(ctx, rsrc, vindex, voffset,
						  soffset, 1, dfmt, nfmt, glc,
						  false, true, true);
	} else {
		const char *name = "llvm.amdgcn.tbuffer.load.i32";
		LLVMTypeRef type = ctx->i32;
		LLVMValueRef params[] = {
					rsrc,
					vindex,
					voffset,
					soffset,
					immoffset,
					LLVMConstInt(ctx->i32, dfmt, false),
					LLVMConstInt(ctx->i32, nfmt, false),
					glc,
					ctx->i1false,
		};
		res = ac_build_intrinsic(ctx, name, type, params, 9, 0);
	}

	return LLVMBuildTrunc(ctx->builder, res, ctx->i16, "");
}

LLVMValueRef
ac_build_llvm8_tbuffer_load(struct ac_llvm_context *ctx,
			    LLVMValueRef rsrc,
			    LLVMValueRef vindex,
			    LLVMValueRef voffset,
			    LLVMValueRef soffset,
			    unsigned num_channels,
			    unsigned dfmt,
			    unsigned nfmt,
			    bool glc,
			    bool slc,
			    bool can_speculate,
			    bool structurized)
{
	LLVMValueRef args[6];
	int idx = 0;
	args[idx++] = LLVMBuildBitCast(ctx->builder, rsrc, ctx->v4i32, "");
	if (structurized)
		args[idx++] = vindex ? vindex : ctx->i32_0;
	args[idx++] = voffset ? voffset : ctx->i32_0;
	args[idx++] = soffset ? soffset : ctx->i32_0;
	args[idx++] = LLVMConstInt(ctx->i32, dfmt | (nfmt << 4), 0);
	args[idx++] = LLVMConstInt(ctx->i32, (glc ? 1 : 0) + (slc ? 2 : 0), 0);
	unsigned func = CLAMP(num_channels, 1, 3) - 1;

	LLVMTypeRef types[] = {ctx->i32, ctx->v2i32, ctx->v4i32};
	const char *type_names[] = {"i32", "v2i32", "v4i32"};
	const char *indexing_kind = structurized ? "struct" : "raw";
	char name[256];

	snprintf(name, sizeof(name), "llvm.amdgcn.%s.tbuffer.load.%s",
		 indexing_kind, type_names[func]);

	return ac_build_intrinsic(ctx, name, types[func], args,
				  idx,
				  ac_get_load_intr_attribs(can_speculate));
}

/**
 * Set range metadata on an instruction.  This can only be used on load and
 * call instructions.  If you know an instruction can only produce the values
 * 0, 1, 2, you would do set_range_metadata(value, 0, 3);
 * \p lo is the minimum value inclusive.
 * \p hi is the maximum value exclusive.
 */
static void set_range_metadata(struct ac_llvm_context *ctx,
			       LLVMValueRef value, unsigned lo, unsigned hi)
{
	LLVMValueRef range_md, md_args[2];
	LLVMTypeRef type = LLVMTypeOf(value);
	LLVMContextRef context = LLVMGetTypeContext(type);

	md_args[0] = LLVMConstInt(type, lo, false);
	md_args[1] = LLVMConstInt(type, hi, false);
	range_md = LLVMMDNodeInContext(context, md_args, 2);
	LLVMSetMetadata(value, ctx->range_md_kind, range_md);
}

LLVMValueRef
ac_get_thread_id(struct ac_llvm_context *ctx)
{
	LLVMValueRef tid;

	LLVMValueRef tid_args[2];
	tid_args[0] = LLVMConstInt(ctx->i32, 0xffffffff, false);
	tid_args[1] = ctx->i32_0;
	tid_args[1] = ac_build_intrinsic(ctx,
					 "llvm.amdgcn.mbcnt.lo", ctx->i32,
					 tid_args, 2, AC_FUNC_ATTR_READNONE);

	tid = ac_build_intrinsic(ctx, "llvm.amdgcn.mbcnt.hi",
				 ctx->i32, tid_args,
				 2, AC_FUNC_ATTR_READNONE);
	set_range_metadata(ctx, tid, 0, 64);
	return tid;
}

/*
 * SI implements derivatives using the local data store (LDS)
 * All writes to the LDS happen in all executing threads at
 * the same time. TID is the Thread ID for the current
 * thread and is a value between 0 and 63, representing
 * the thread's position in the wavefront.
 *
 * For the pixel shader threads are grouped into quads of four pixels.
 * The TIDs of the pixels of a quad are:
 *
 *  +------+------+
 *  |4n + 0|4n + 1|
 *  +------+------+
 *  |4n + 2|4n + 3|
 *  +------+------+
 *
 * So, masking the TID with 0xfffffffc yields the TID of the top left pixel
 * of the quad, masking with 0xfffffffd yields the TID of the top pixel of
 * the current pixel's column, and masking with 0xfffffffe yields the TID
 * of the left pixel of the current pixel's row.
 *
 * Adding 1 yields the TID of the pixel to the right of the left pixel, and
 * adding 2 yields the TID of the pixel below the top pixel.
 */
LLVMValueRef
ac_build_ddxy(struct ac_llvm_context *ctx,
	      uint32_t mask,
	      int idx,
	      LLVMValueRef val)
{
	unsigned tl_lanes[4], trbl_lanes[4];
	LLVMValueRef tl, trbl;
	LLVMValueRef result;

	for (unsigned i = 0; i < 4; ++i) {
		tl_lanes[i] = i & mask;
		trbl_lanes[i] = (i & mask) + idx;
	}

	tl = ac_build_quad_swizzle(ctx, val,
				   tl_lanes[0], tl_lanes[1],
				   tl_lanes[2], tl_lanes[3]);
	trbl = ac_build_quad_swizzle(ctx, val,
				     trbl_lanes[0], trbl_lanes[1],
				     trbl_lanes[2], trbl_lanes[3]);

	tl = LLVMBuildBitCast(ctx->builder, tl, ctx->f32, "");
	trbl = LLVMBuildBitCast(ctx->builder, trbl, ctx->f32, "");
	result = LLVMBuildFSub(ctx->builder, trbl, tl, "");

	result = ac_build_intrinsic(ctx, "llvm.amdgcn.wqm.f32", ctx->f32,
				    &result, 1, 0);

	return result;
}

void
ac_build_sendmsg(struct ac_llvm_context *ctx,
		 uint32_t msg,
		 LLVMValueRef wave_id)
{
	LLVMValueRef args[2];
	args[0] = LLVMConstInt(ctx->i32, msg, false);
	args[1] = wave_id;
	ac_build_intrinsic(ctx, "llvm.amdgcn.s.sendmsg", ctx->voidt, args, 2, 0);
}

LLVMValueRef
ac_build_imsb(struct ac_llvm_context *ctx,
	      LLVMValueRef arg,
	      LLVMTypeRef dst_type)
{
	LLVMValueRef msb = ac_build_intrinsic(ctx, "llvm.amdgcn.sffbh.i32",
					      dst_type, &arg, 1,
					      AC_FUNC_ATTR_READNONE);

	/* The HW returns the last bit index from MSB, but NIR/TGSI wants
	 * the index from LSB. Invert it by doing "31 - msb". */
	msb = LLVMBuildSub(ctx->builder, LLVMConstInt(ctx->i32, 31, false),
			   msb, "");

	LLVMValueRef all_ones = LLVMConstInt(ctx->i32, -1, true);
	LLVMValueRef cond = LLVMBuildOr(ctx->builder,
					LLVMBuildICmp(ctx->builder, LLVMIntEQ,
						      arg, ctx->i32_0, ""),
					LLVMBuildICmp(ctx->builder, LLVMIntEQ,
						      arg, all_ones, ""), "");

	return LLVMBuildSelect(ctx->builder, cond, all_ones, msb, "");
}

LLVMValueRef
ac_build_umsb(struct ac_llvm_context *ctx,
	      LLVMValueRef arg,
	      LLVMTypeRef dst_type)
{
	const char *intrin_name;
	LLVMTypeRef type;
	LLVMValueRef highest_bit;
	LLVMValueRef zero;
	unsigned bitsize;

	bitsize = ac_get_elem_bits(ctx, LLVMTypeOf(arg));
	switch (bitsize) {
	case 64:
		intrin_name = "llvm.ctlz.i64";
		type = ctx->i64;
		highest_bit = LLVMConstInt(ctx->i64, 63, false);
		zero = ctx->i64_0;
		break;
	case 32:
		intrin_name = "llvm.ctlz.i32";
		type = ctx->i32;
		highest_bit = LLVMConstInt(ctx->i32, 31, false);
		zero = ctx->i32_0;
		break;
	case 16:
		intrin_name = "llvm.ctlz.i16";
		type = ctx->i16;
		highest_bit = LLVMConstInt(ctx->i16, 15, false);
		zero = ctx->i16_0;
		break;
	default:
		unreachable(!"invalid bitsize");
		break;
	}

	LLVMValueRef params[2] = {
		arg,
		ctx->i1true,
	};

	LLVMValueRef msb = ac_build_intrinsic(ctx, intrin_name, type,
					      params, 2,
					      AC_FUNC_ATTR_READNONE);

	/* The HW returns the last bit index from MSB, but TGSI/NIR wants
	 * the index from LSB. Invert it by doing "31 - msb". */
	msb = LLVMBuildSub(ctx->builder, highest_bit, msb, "");
	msb = LLVMBuildTruncOrBitCast(ctx->builder, msb, ctx->i32, "");

	/* check for zero */
	return LLVMBuildSelect(ctx->builder,
			       LLVMBuildICmp(ctx->builder, LLVMIntEQ, arg, zero, ""),
			       LLVMConstInt(ctx->i32, -1, true), msb, "");
}

LLVMValueRef ac_build_fmin(struct ac_llvm_context *ctx, LLVMValueRef a,
			   LLVMValueRef b)
{
	char name[64];
	snprintf(name, sizeof(name), "llvm.minnum.f%d", ac_get_elem_bits(ctx, LLVMTypeOf(a)));
	LLVMValueRef args[2] = {a, b};
	return ac_build_intrinsic(ctx, name, LLVMTypeOf(a), args, 2,
				  AC_FUNC_ATTR_READNONE);
}

LLVMValueRef ac_build_fmax(struct ac_llvm_context *ctx, LLVMValueRef a,
			   LLVMValueRef b)
{
	char name[64];
	snprintf(name, sizeof(name), "llvm.maxnum.f%d", ac_get_elem_bits(ctx, LLVMTypeOf(a)));
	LLVMValueRef args[2] = {a, b};
	return ac_build_intrinsic(ctx, name, LLVMTypeOf(a), args, 2,
				  AC_FUNC_ATTR_READNONE);
}

LLVMValueRef ac_build_imin(struct ac_llvm_context *ctx, LLVMValueRef a,
			   LLVMValueRef b)
{
	LLVMValueRef cmp = LLVMBuildICmp(ctx->builder, LLVMIntSLE, a, b, "");
	return LLVMBuildSelect(ctx->builder, cmp, a, b, "");
}

LLVMValueRef ac_build_imax(struct ac_llvm_context *ctx, LLVMValueRef a,
			   LLVMValueRef b)
{
	LLVMValueRef cmp = LLVMBuildICmp(ctx->builder, LLVMIntSGT, a, b, "");
	return LLVMBuildSelect(ctx->builder, cmp, a, b, "");
}

LLVMValueRef ac_build_umin(struct ac_llvm_context *ctx, LLVMValueRef a,
			   LLVMValueRef b)
{
	LLVMValueRef cmp = LLVMBuildICmp(ctx->builder, LLVMIntULE, a, b, "");
	return LLVMBuildSelect(ctx->builder, cmp, a, b, "");
}

LLVMValueRef ac_build_clamp(struct ac_llvm_context *ctx, LLVMValueRef value)
{
	LLVMTypeRef t = LLVMTypeOf(value);
	return ac_build_fmin(ctx, ac_build_fmax(ctx, value, LLVMConstReal(t, 0.0)),
			     LLVMConstReal(t, 1.0));
}

void ac_build_export(struct ac_llvm_context *ctx, struct ac_export_args *a)
{
	LLVMValueRef args[9];

	args[0] = LLVMConstInt(ctx->i32, a->target, 0);
	args[1] = LLVMConstInt(ctx->i32, a->enabled_channels, 0);

	if (a->compr) {
		LLVMTypeRef i16 = LLVMInt16TypeInContext(ctx->context);
		LLVMTypeRef v2i16 = LLVMVectorType(i16, 2);

		args[2] = LLVMBuildBitCast(ctx->builder, a->out[0],
				v2i16, "");
		args[3] = LLVMBuildBitCast(ctx->builder, a->out[1],
				v2i16, "");
		args[4] = LLVMConstInt(ctx->i1, a->done, 0);
		args[5] = LLVMConstInt(ctx->i1, a->valid_mask, 0);

		ac_build_intrinsic(ctx, "llvm.amdgcn.exp.compr.v2i16",
				   ctx->voidt, args, 6, 0);
	} else {
		args[2] = a->out[0];
		args[3] = a->out[1];
		args[4] = a->out[2];
		args[5] = a->out[3];
		args[6] = LLVMConstInt(ctx->i1, a->done, 0);
		args[7] = LLVMConstInt(ctx->i1, a->valid_mask, 0);

		ac_build_intrinsic(ctx, "llvm.amdgcn.exp.f32",
				   ctx->voidt, args, 8, 0);
	}
}

void ac_build_export_null(struct ac_llvm_context *ctx)
{
	struct ac_export_args args;

	args.enabled_channels = 0x0; /* enabled channels */
	args.valid_mask = 1; /* whether the EXEC mask is valid */
	args.done = 1; /* DONE bit */
	args.target = V_008DFC_SQ_EXP_NULL;
	args.compr = 0; /* COMPR flag (0 = 32-bit export) */
	args.out[0] = LLVMGetUndef(ctx->f32); /* R */
	args.out[1] = LLVMGetUndef(ctx->f32); /* G */
	args.out[2] = LLVMGetUndef(ctx->f32); /* B */
	args.out[3] = LLVMGetUndef(ctx->f32); /* A */

	ac_build_export(ctx, &args);
}

static unsigned ac_num_coords(enum ac_image_dim dim)
{
	switch (dim) {
	case ac_image_1d:
		return 1;
	case ac_image_2d:
	case ac_image_1darray:
		 return 2;
	case ac_image_3d:
	case ac_image_cube:
	case ac_image_2darray:
	case ac_image_2dmsaa:
		return 3;
	case ac_image_2darraymsaa:
		return 4;
	default:
		unreachable("ac_num_coords: bad dim");
	}
}

static unsigned ac_num_derivs(enum ac_image_dim dim)
{
	switch (dim) {
	case ac_image_1d:
	case ac_image_1darray:
		return 2;
	case ac_image_2d:
	case ac_image_2darray:
	case ac_image_cube:
		return 4;
	case ac_image_3d:
		return 6;
	case ac_image_2dmsaa:
	case ac_image_2darraymsaa:
	default:
		unreachable("derivatives not supported");
	}
}

static const char *get_atomic_name(enum ac_atomic_op op)
{
	switch (op) {
	case ac_atomic_swap: return "swap";
	case ac_atomic_add: return "add";
	case ac_atomic_sub: return "sub";
	case ac_atomic_smin: return "smin";
	case ac_atomic_umin: return "umin";
	case ac_atomic_smax: return "smax";
	case ac_atomic_umax: return "umax";
	case ac_atomic_and: return "and";
	case ac_atomic_or: return "or";
	case ac_atomic_xor: return "xor";
	}
	unreachable("bad atomic op");
}

LLVMValueRef ac_build_image_opcode(struct ac_llvm_context *ctx,
				   struct ac_image_args *a)
{
	const char *overload[3] = { "", "", "" };
	unsigned num_overloads = 0;
	LLVMValueRef args[18];
	unsigned num_args = 0;
	enum ac_image_dim dim = a->dim;

	assert(!a->lod || a->lod == ctx->i32_0 || a->lod == ctx->f32_0 ||
	       !a->level_zero);
	assert((a->opcode != ac_image_get_resinfo && a->opcode != ac_image_load_mip &&
		a->opcode != ac_image_store_mip) ||
	       a->lod);
	assert(a->opcode == ac_image_sample || a->opcode == ac_image_gather4 ||
	       (!a->compare && !a->offset));
	assert((a->opcode == ac_image_sample || a->opcode == ac_image_gather4 ||
		a->opcode == ac_image_get_lod) ||
	       !a->bias);
	assert((a->bias ? 1 : 0) +
	       (a->lod ? 1 : 0) +
	       (a->level_zero ? 1 : 0) +
	       (a->derivs[0] ? 1 : 0) <= 1);

	if (a->opcode == ac_image_get_lod) {
		switch (dim) {
		case ac_image_1darray:
			dim = ac_image_1d;
			break;
		case ac_image_2darray:
		case ac_image_cube:
			dim = ac_image_2d;
			break;
		default:
			break;
		}
	}

	bool sample = a->opcode == ac_image_sample ||
		      a->opcode == ac_image_gather4 ||
		      a->opcode == ac_image_get_lod;
	bool atomic = a->opcode == ac_image_atomic ||
		      a->opcode == ac_image_atomic_cmpswap;
	LLVMTypeRef coord_type = sample ? ctx->f32 : ctx->i32;

	if (atomic || a->opcode == ac_image_store || a->opcode == ac_image_store_mip) {
		args[num_args++] = a->data[0];
		if (a->opcode == ac_image_atomic_cmpswap)
			args[num_args++] = a->data[1];
	}

	if (!atomic)
		args[num_args++] = LLVMConstInt(ctx->i32, a->dmask, false);

	if (a->offset)
		args[num_args++] = ac_to_integer(ctx, a->offset);
	if (a->bias) {
		args[num_args++] = ac_to_float(ctx, a->bias);
		overload[num_overloads++] = ".f32";
	}
	if (a->compare)
		args[num_args++] = ac_to_float(ctx, a->compare);
	if (a->derivs[0]) {
		unsigned count = ac_num_derivs(dim);
		for (unsigned i = 0; i < count; ++i)
			args[num_args++] = ac_to_float(ctx, a->derivs[i]);
		overload[num_overloads++] = ".f32";
	}
	unsigned num_coords =
		a->opcode != ac_image_get_resinfo ? ac_num_coords(dim) : 0;
	for (unsigned i = 0; i < num_coords; ++i)
		args[num_args++] = LLVMBuildBitCast(ctx->builder, a->coords[i], coord_type, "");
	if (a->lod)
		args[num_args++] = LLVMBuildBitCast(ctx->builder, a->lod, coord_type, "");
	overload[num_overloads++] = sample ? ".f32" : ".i32";

	args[num_args++] = a->resource;
	if (sample) {
		args[num_args++] = a->sampler;
		args[num_args++] = LLVMConstInt(ctx->i1, a->unorm, false);
	}

	args[num_args++] = ctx->i32_0; /* texfailctrl */
	args[num_args++] = LLVMConstInt(ctx->i32, a->cache_policy, false);

	const char *name;
	const char *atomic_subop = "";
	switch (a->opcode) {
	case ac_image_sample: name = "sample"; break;
	case ac_image_gather4: name = "gather4"; break;
	case ac_image_load: name = "load"; break;
	case ac_image_load_mip: name = "load.mip"; break;
	case ac_image_store: name = "store"; break;
	case ac_image_store_mip: name = "store.mip"; break;
	case ac_image_atomic:
		name = "atomic.";
		atomic_subop = get_atomic_name(a->atomic);
		break;
	case ac_image_atomic_cmpswap:
		name = "atomic.";
		atomic_subop = "cmpswap";
		break;
	case ac_image_get_lod: name = "getlod"; break;
	case ac_image_get_resinfo: name = "getresinfo"; break;
	default: unreachable("invalid image opcode");
	}

	const char *dimname;
	switch (dim) {
	case ac_image_1d: dimname = "1d"; break;
	case ac_image_2d: dimname = "2d"; break;
	case ac_image_3d: dimname = "3d"; break;
	case ac_image_cube: dimname = "cube"; break;
	case ac_image_1darray: dimname = "1darray"; break;
	case ac_image_2darray: dimname = "2darray"; break;
	case ac_image_2dmsaa: dimname = "2dmsaa"; break;
	case ac_image_2darraymsaa: dimname = "2darraymsaa"; break;
	default: unreachable("invalid dim");
	}

	bool lod_suffix =
		a->lod && (a->opcode == ac_image_sample || a->opcode == ac_image_gather4);
	char intr_name[96];
	snprintf(intr_name, sizeof(intr_name),
		 "llvm.amdgcn.image.%s%s" /* base name */
		 "%s%s%s" /* sample/gather modifiers */
		 ".%s.%s%s%s%s", /* dimension and type overloads */
		 name, atomic_subop,
		 a->compare ? ".c" : "",
		 a->bias ? ".b" :
		 lod_suffix ? ".l" :
		 a->derivs[0] ? ".d" :
		 a->level_zero ? ".lz" : "",
		 a->offset ? ".o" : "",
		 dimname,
		 atomic ? "i32" : "v4f32",
		 overload[0], overload[1], overload[2]);

	LLVMTypeRef retty;
	if (atomic)
		retty = ctx->i32;
	else if (a->opcode == ac_image_store || a->opcode == ac_image_store_mip)
		retty = ctx->voidt;
	else
		retty = ctx->v4f32;

	LLVMValueRef result =
		ac_build_intrinsic(ctx, intr_name, retty, args, num_args,
				   a->attributes);
	if (!sample && retty == ctx->v4f32) {
		result = LLVMBuildBitCast(ctx->builder, result,
					  ctx->v4i32, "");
	}
	return result;
}

LLVMValueRef ac_build_cvt_pkrtz_f16(struct ac_llvm_context *ctx,
				    LLVMValueRef args[2])
{
	LLVMTypeRef v2f16 =
		LLVMVectorType(LLVMHalfTypeInContext(ctx->context), 2);

	return ac_build_intrinsic(ctx, "llvm.amdgcn.cvt.pkrtz", v2f16,
				  args, 2, AC_FUNC_ATTR_READNONE);
}

LLVMValueRef ac_build_cvt_pknorm_i16(struct ac_llvm_context *ctx,
				     LLVMValueRef args[2])
{
	LLVMValueRef res =
		ac_build_intrinsic(ctx, "llvm.amdgcn.cvt.pknorm.i16",
				   ctx->v2i16, args, 2,
				   AC_FUNC_ATTR_READNONE);
	return LLVMBuildBitCast(ctx->builder, res, ctx->i32, "");
}

LLVMValueRef ac_build_cvt_pknorm_u16(struct ac_llvm_context *ctx,
				     LLVMValueRef args[2])
{
	LLVMValueRef res =
		ac_build_intrinsic(ctx, "llvm.amdgcn.cvt.pknorm.u16",
				   ctx->v2i16, args, 2,
				   AC_FUNC_ATTR_READNONE);
	return LLVMBuildBitCast(ctx->builder, res, ctx->i32, "");
}

/* The 8-bit and 10-bit clamping is for HW workarounds. */
LLVMValueRef ac_build_cvt_pk_i16(struct ac_llvm_context *ctx,
				 LLVMValueRef args[2], unsigned bits, bool hi)
{
	assert(bits == 8 || bits == 10 || bits == 16);

	LLVMValueRef max_rgb = LLVMConstInt(ctx->i32,
		bits == 8 ? 127 : bits == 10 ? 511 : 32767, 0);
	LLVMValueRef min_rgb = LLVMConstInt(ctx->i32,
		bits == 8 ? -128 : bits == 10 ? -512 : -32768, 0);
	LLVMValueRef max_alpha =
		bits != 10 ? max_rgb : ctx->i32_1;
	LLVMValueRef min_alpha =
		bits != 10 ? min_rgb : LLVMConstInt(ctx->i32, -2, 0);

	/* Clamp. */
	if (bits != 16) {
		for (int i = 0; i < 2; i++) {
			bool alpha = hi && i == 1;
			args[i] = ac_build_imin(ctx, args[i],
						alpha ? max_alpha : max_rgb);
			args[i] = ac_build_imax(ctx, args[i],
						alpha ? min_alpha : min_rgb);
		}
	}

	LLVMValueRef res =
		ac_build_intrinsic(ctx, "llvm.amdgcn.cvt.pk.i16",
				   ctx->v2i16, args, 2,
				   AC_FUNC_ATTR_READNONE);
	return LLVMBuildBitCast(ctx->builder, res, ctx->i32, "");
}

/* The 8-bit and 10-bit clamping is for HW workarounds. */
LLVMValueRef ac_build_cvt_pk_u16(struct ac_llvm_context *ctx,
				 LLVMValueRef args[2], unsigned bits, bool hi)
{
	assert(bits == 8 || bits == 10 || bits == 16);

	LLVMValueRef max_rgb = LLVMConstInt(ctx->i32,
		bits == 8 ? 255 : bits == 10 ? 1023 : 65535, 0);
	LLVMValueRef max_alpha =
		bits != 10 ? max_rgb : LLVMConstInt(ctx->i32, 3, 0);

	/* Clamp. */
	if (bits != 16) {
		for (int i = 0; i < 2; i++) {
			bool alpha = hi && i == 1;
			args[i] = ac_build_umin(ctx, args[i],
						alpha ? max_alpha : max_rgb);
		}
	}

	LLVMValueRef res =
		ac_build_intrinsic(ctx, "llvm.amdgcn.cvt.pk.u16",
				   ctx->v2i16, args, 2,
				   AC_FUNC_ATTR_READNONE);
	return LLVMBuildBitCast(ctx->builder, res, ctx->i32, "");
}

LLVMValueRef ac_build_wqm_vote(struct ac_llvm_context *ctx, LLVMValueRef i1)
{
	return ac_build_intrinsic(ctx, "llvm.amdgcn.wqm.vote", ctx->i1,
				  &i1, 1, AC_FUNC_ATTR_READNONE);
}

void ac_build_kill_if_false(struct ac_llvm_context *ctx, LLVMValueRef i1)
{
	ac_build_intrinsic(ctx, "llvm.amdgcn.kill", ctx->voidt,
			   &i1, 1, 0);
}

LLVMValueRef ac_build_bfe(struct ac_llvm_context *ctx, LLVMValueRef input,
			  LLVMValueRef offset, LLVMValueRef width,
			  bool is_signed)
{
	LLVMValueRef args[] = {
		input,
		offset,
		width,
	};

	return ac_build_intrinsic(ctx,
				  is_signed ? "llvm.amdgcn.sbfe.i32" :
					      "llvm.amdgcn.ubfe.i32",
				  ctx->i32, args, 3,
				  AC_FUNC_ATTR_READNONE);
}

LLVMValueRef ac_build_imad(struct ac_llvm_context *ctx, LLVMValueRef s0,
			   LLVMValueRef s1, LLVMValueRef s2)
{
	return LLVMBuildAdd(ctx->builder,
			    LLVMBuildMul(ctx->builder, s0, s1, ""), s2, "");
}

LLVMValueRef ac_build_fmad(struct ac_llvm_context *ctx, LLVMValueRef s0,
			   LLVMValueRef s1, LLVMValueRef s2)
{
	return LLVMBuildFAdd(ctx->builder,
			     LLVMBuildFMul(ctx->builder, s0, s1, ""), s2, "");
}

void ac_build_waitcnt(struct ac_llvm_context *ctx, unsigned simm16)
{
	LLVMValueRef args[1] = {
		LLVMConstInt(ctx->i32, simm16, false),
	};
	ac_build_intrinsic(ctx, "llvm.amdgcn.s.waitcnt",
			   ctx->voidt, args, 1, 0);
}

LLVMValueRef ac_build_fract(struct ac_llvm_context *ctx, LLVMValueRef src0,
			    unsigned bitsize)
{
	LLVMTypeRef type;
	char *intr;

	if (bitsize == 32) {
		intr = "llvm.floor.f32";
		type = ctx->f32;
	} else {
		intr = "llvm.floor.f64";
		type = ctx->f64;
	}

	LLVMValueRef params[] = {
		src0,
	};
	LLVMValueRef floor = ac_build_intrinsic(ctx, intr, type, params, 1,
						AC_FUNC_ATTR_READNONE);
	return LLVMBuildFSub(ctx->builder, src0, floor, "");
}

LLVMValueRef ac_build_isign(struct ac_llvm_context *ctx, LLVMValueRef src0,
			    unsigned bitsize)
{
	LLVMValueRef cmp, val, zero, one;
	LLVMTypeRef type;

	switch (bitsize) {
	case 64:
		type = ctx->i64;
		zero = ctx->i64_0;
		one = ctx->i64_1;
		break;
	case 32:
		type = ctx->i32;
		zero = ctx->i32_0;
		one = ctx->i32_1;
		break;
	case 16:
		type = ctx->i16;
		zero = ctx->i16_0;
		one = ctx->i16_1;
		break;
	default:
		unreachable(!"invalid bitsize");
		break;
	}

	cmp = LLVMBuildICmp(ctx->builder, LLVMIntSGT, src0, zero, "");
	val = LLVMBuildSelect(ctx->builder, cmp, one, src0, "");
	cmp = LLVMBuildICmp(ctx->builder, LLVMIntSGE, val, zero, "");
	val = LLVMBuildSelect(ctx->builder, cmp, val, LLVMConstInt(type, -1, true), "");
	return val;
}

LLVMValueRef ac_build_fsign(struct ac_llvm_context *ctx, LLVMValueRef src0,
			    unsigned bitsize)
{
	LLVMValueRef cmp, val, zero, one;
	LLVMTypeRef type;

	if (bitsize == 32) {
		type = ctx->f32;
		zero = ctx->f32_0;
		one = ctx->f32_1;
	} else {
		type = ctx->f64;
		zero = ctx->f64_0;
		one = ctx->f64_1;
	}

	cmp = LLVMBuildFCmp(ctx->builder, LLVMRealOGT, src0, zero, "");
	val = LLVMBuildSelect(ctx->builder, cmp, one, src0, "");
	cmp = LLVMBuildFCmp(ctx->builder, LLVMRealOGE, val, zero, "");
	val = LLVMBuildSelect(ctx->builder, cmp, val, LLVMConstReal(type, -1.0), "");
	return val;
}

LLVMValueRef ac_build_bit_count(struct ac_llvm_context *ctx, LLVMValueRef src0)
{
	LLVMValueRef result;
	unsigned bitsize;

	bitsize = ac_get_elem_bits(ctx, LLVMTypeOf(src0));

	switch (bitsize) {
	case 64:
		result = ac_build_intrinsic(ctx, "llvm.ctpop.i64", ctx->i64,
					    (LLVMValueRef []) { src0 }, 1,
					    AC_FUNC_ATTR_READNONE);

		result = LLVMBuildTrunc(ctx->builder, result, ctx->i32, "");
		break;
	case 32:
		result = ac_build_intrinsic(ctx, "llvm.ctpop.i32", ctx->i32,
					    (LLVMValueRef []) { src0 }, 1,
					    AC_FUNC_ATTR_READNONE);
		break;
	case 16:
		result = ac_build_intrinsic(ctx, "llvm.ctpop.i16", ctx->i16,
					    (LLVMValueRef []) { src0 }, 1,
					    AC_FUNC_ATTR_READNONE);
		break;
	default:
		unreachable(!"invalid bitsize");
		break;
	}

	return result;
}

LLVMValueRef ac_build_bitfield_reverse(struct ac_llvm_context *ctx,
				       LLVMValueRef src0)
{
	LLVMValueRef result;
	unsigned bitsize;

	bitsize = ac_get_elem_bits(ctx, LLVMTypeOf(src0));

	switch (bitsize) {
	case 32:
		result = ac_build_intrinsic(ctx, "llvm.bitreverse.i32", ctx->i32,
					    (LLVMValueRef []) { src0 }, 1,
					    AC_FUNC_ATTR_READNONE);
		break;
	case 16:
		result = ac_build_intrinsic(ctx, "llvm.bitreverse.i16", ctx->i16,
					    (LLVMValueRef []) { src0 }, 1,
					    AC_FUNC_ATTR_READNONE);
		break;
	default:
		unreachable(!"invalid bitsize");
		break;
	}

	return result;
}

#define AC_EXP_TARGET		0
#define AC_EXP_ENABLED_CHANNELS 1
#define AC_EXP_OUT0		2

enum ac_ir_type {
	AC_IR_UNDEF,
	AC_IR_CONST,
	AC_IR_VALUE,
};

struct ac_vs_exp_chan
{
	LLVMValueRef value;
	float const_float;
	enum ac_ir_type type;
};

struct ac_vs_exp_inst {
	unsigned offset;
	LLVMValueRef inst;
	struct ac_vs_exp_chan chan[4];
};

struct ac_vs_exports {
	unsigned num;
	struct ac_vs_exp_inst exp[VARYING_SLOT_MAX];
};

/* Return true if the PARAM export has been eliminated. */
static bool ac_eliminate_const_output(uint8_t *vs_output_param_offset,
				      uint32_t num_outputs,
				      struct ac_vs_exp_inst *exp)
{
	unsigned i, default_val; /* SPI_PS_INPUT_CNTL_i.DEFAULT_VAL */
	bool is_zero[4] = {}, is_one[4] = {};

	for (i = 0; i < 4; i++) {
		/* It's a constant expression. Undef outputs are eliminated too. */
		if (exp->chan[i].type == AC_IR_UNDEF) {
			is_zero[i] = true;
			is_one[i] = true;
		} else if (exp->chan[i].type == AC_IR_CONST) {
			if (exp->chan[i].const_float == 0)
				is_zero[i] = true;
			else if (exp->chan[i].const_float == 1)
				is_one[i] = true;
			else
				return false; /* other constant */
		} else
			return false;
	}

	/* Only certain combinations of 0 and 1 can be eliminated. */
	if (is_zero[0] && is_zero[1] && is_zero[2])
		default_val = is_zero[3] ? 0 : 1;
	else if (is_one[0] && is_one[1] && is_one[2])
		default_val = is_zero[3] ? 2 : 3;
	else
		return false;

	/* The PARAM export can be represented as DEFAULT_VAL. Kill it. */
	LLVMInstructionEraseFromParent(exp->inst);

	/* Change OFFSET to DEFAULT_VAL. */
	for (i = 0; i < num_outputs; i++) {
		if (vs_output_param_offset[i] == exp->offset) {
			vs_output_param_offset[i] =
				AC_EXP_PARAM_DEFAULT_VAL_0000 + default_val;
			break;
		}
	}
	return true;
}

static bool ac_eliminate_duplicated_output(struct ac_llvm_context *ctx,
					   uint8_t *vs_output_param_offset,
					   uint32_t num_outputs,
					   struct ac_vs_exports *processed,
				           struct ac_vs_exp_inst *exp)
{
	unsigned p, copy_back_channels = 0;

	/* See if the output is already in the list of processed outputs.
	 * The LLVMValueRef comparison relies on SSA.
	 */
	for (p = 0; p < processed->num; p++) {
		bool different = false;

		for (unsigned j = 0; j < 4; j++) {
			struct ac_vs_exp_chan *c1 = &processed->exp[p].chan[j];
			struct ac_vs_exp_chan *c2 = &exp->chan[j];

			/* Treat undef as a match. */
			if (c2->type == AC_IR_UNDEF)
				continue;

			/* If c1 is undef but c2 isn't, we can copy c2 to c1
			 * and consider the instruction duplicated.
			 */
			if (c1->type == AC_IR_UNDEF) {
				copy_back_channels |= 1 << j;
				continue;
			}

			/* Test whether the channels are not equal. */
			if (c1->type != c2->type ||
			    (c1->type == AC_IR_CONST &&
			     c1->const_float != c2->const_float) ||
			    (c1->type == AC_IR_VALUE &&
			     c1->value != c2->value)) {
				different = true;
				break;
			}
		}
		if (!different)
			break;

		copy_back_channels = 0;
	}
	if (p == processed->num)
		return false;

	/* If a match was found, but the matching export has undef where the new
	 * one has a normal value, copy the normal value to the undef channel.
	 */
	struct ac_vs_exp_inst *match = &processed->exp[p];

	/* Get current enabled channels mask. */
	LLVMValueRef arg = LLVMGetOperand(match->inst, AC_EXP_ENABLED_CHANNELS);
	unsigned enabled_channels = LLVMConstIntGetZExtValue(arg);

	while (copy_back_channels) {
		unsigned chan = u_bit_scan(&copy_back_channels);

		assert(match->chan[chan].type == AC_IR_UNDEF);
		LLVMSetOperand(match->inst, AC_EXP_OUT0 + chan,
			       exp->chan[chan].value);
		match->chan[chan] = exp->chan[chan];

		/* Update number of enabled channels because the original mask
		 * is not always 0xf.
		 */
		enabled_channels |= (1 << chan);
		LLVMSetOperand(match->inst, AC_EXP_ENABLED_CHANNELS,
			       LLVMConstInt(ctx->i32, enabled_channels, 0));
	}

	/* The PARAM export is duplicated. Kill it. */
	LLVMInstructionEraseFromParent(exp->inst);

	/* Change OFFSET to the matching export. */
	for (unsigned i = 0; i < num_outputs; i++) {
		if (vs_output_param_offset[i] == exp->offset) {
			vs_output_param_offset[i] = match->offset;
			break;
		}
	}
	return true;
}

void ac_optimize_vs_outputs(struct ac_llvm_context *ctx,
			    LLVMValueRef main_fn,
			    uint8_t *vs_output_param_offset,
			    uint32_t num_outputs,
			    uint8_t *num_param_exports)
{
	LLVMBasicBlockRef bb;
	bool removed_any = false;
	struct ac_vs_exports exports;

	exports.num = 0;

	/* Process all LLVM instructions. */
	bb = LLVMGetFirstBasicBlock(main_fn);
	while (bb) {
		LLVMValueRef inst = LLVMGetFirstInstruction(bb);

		while (inst) {
			LLVMValueRef cur = inst;
			inst = LLVMGetNextInstruction(inst);
			struct ac_vs_exp_inst exp;

			if (LLVMGetInstructionOpcode(cur) != LLVMCall)
				continue;

			LLVMValueRef callee = ac_llvm_get_called_value(cur);

			if (!ac_llvm_is_function(callee))
				continue;

			const char *name = LLVMGetValueName(callee);
			unsigned num_args = LLVMCountParams(callee);

			/* Check if this is an export instruction. */
			if ((num_args != 9 && num_args != 8) ||
			    (strcmp(name, "llvm.SI.export") &&
			     strcmp(name, "llvm.amdgcn.exp.f32")))
				continue;

			LLVMValueRef arg = LLVMGetOperand(cur, AC_EXP_TARGET);
			unsigned target = LLVMConstIntGetZExtValue(arg);

			if (target < V_008DFC_SQ_EXP_PARAM)
				continue;

			target -= V_008DFC_SQ_EXP_PARAM;

			/* Parse the instruction. */
			memset(&exp, 0, sizeof(exp));
			exp.offset = target;
			exp.inst = cur;

			for (unsigned i = 0; i < 4; i++) {
				LLVMValueRef v = LLVMGetOperand(cur, AC_EXP_OUT0 + i);

				exp.chan[i].value = v;

				if (LLVMIsUndef(v)) {
					exp.chan[i].type = AC_IR_UNDEF;
				} else if (LLVMIsAConstantFP(v)) {
					LLVMBool loses_info;
					exp.chan[i].type = AC_IR_CONST;
					exp.chan[i].const_float =
						LLVMConstRealGetDouble(v, &loses_info);
				} else {
					exp.chan[i].type = AC_IR_VALUE;
				}
			}

			/* Eliminate constant and duplicated PARAM exports. */
			if (ac_eliminate_const_output(vs_output_param_offset,
						      num_outputs, &exp) ||
			    ac_eliminate_duplicated_output(ctx,
							   vs_output_param_offset,
							   num_outputs, &exports,
							   &exp)) {
				removed_any = true;
			} else {
				exports.exp[exports.num++] = exp;
			}
		}
		bb = LLVMGetNextBasicBlock(bb);
	}

	/* Remove holes in export memory due to removed PARAM exports.
	 * This is done by renumbering all PARAM exports.
	 */
	if (removed_any) {
		uint8_t old_offset[VARYING_SLOT_MAX];
		unsigned out, i;

		/* Make a copy of the offsets. We need the old version while
		 * we are modifying some of them. */
		memcpy(old_offset, vs_output_param_offset,
		       sizeof(old_offset));

		for (i = 0; i < exports.num; i++) {
			unsigned offset = exports.exp[i].offset;

			/* Update vs_output_param_offset. Multiple outputs can
			 * have the same offset.
			 */
			for (out = 0; out < num_outputs; out++) {
				if (old_offset[out] == offset)
					vs_output_param_offset[out] = i;
			}

			/* Change the PARAM offset in the instruction. */
			LLVMSetOperand(exports.exp[i].inst, AC_EXP_TARGET,
				       LLVMConstInt(ctx->i32,
						    V_008DFC_SQ_EXP_PARAM + i, 0));
		}
		*num_param_exports = exports.num;
	}
}

void ac_init_exec_full_mask(struct ac_llvm_context *ctx)
{
	LLVMValueRef full_mask = LLVMConstInt(ctx->i64, ~0ull, 0);
	ac_build_intrinsic(ctx,
			   "llvm.amdgcn.init.exec", ctx->voidt,
			   &full_mask, 1, AC_FUNC_ATTR_CONVERGENT);
}

void ac_declare_lds_as_pointer(struct ac_llvm_context *ctx)
{
	unsigned lds_size = ctx->chip_class >= CIK ? 65536 : 32768;
	ctx->lds = LLVMBuildIntToPtr(ctx->builder, ctx->i32_0,
				     LLVMPointerType(LLVMArrayType(ctx->i32, lds_size / 4), AC_ADDR_SPACE_LDS),
				     "lds");
}

LLVMValueRef ac_lds_load(struct ac_llvm_context *ctx,
			 LLVMValueRef dw_addr)
{
	return ac_build_load(ctx, ctx->lds, dw_addr);
}

void ac_lds_store(struct ac_llvm_context *ctx,
		  LLVMValueRef dw_addr,
		  LLVMValueRef value)
{
	value = ac_to_integer(ctx, value);
	ac_build_indexed_store(ctx, ctx->lds,
			       dw_addr, value);
}

LLVMValueRef ac_find_lsb(struct ac_llvm_context *ctx,
			 LLVMTypeRef dst_type,
			 LLVMValueRef src0)
{
	unsigned src0_bitsize = ac_get_elem_bits(ctx, LLVMTypeOf(src0));
	const char *intrin_name;
	LLVMTypeRef type;
	LLVMValueRef zero;

	switch (src0_bitsize) {
	case 64:
		intrin_name = "llvm.cttz.i64";
		type = ctx->i64;
		zero = ctx->i64_0;
		break;
	case 32:
		intrin_name = "llvm.cttz.i32";
		type = ctx->i32;
		zero = ctx->i32_0;
		break;
	case 16:
		intrin_name = "llvm.cttz.i16";
		type = ctx->i16;
		zero = ctx->i16_0;
		break;
	default:
		unreachable(!"invalid bitsize");
	}

	LLVMValueRef params[2] = {
		src0,

		/* The value of 1 means that ffs(x=0) = undef, so LLVM won't
		 * add special code to check for x=0. The reason is that
		 * the LLVM behavior for x=0 is different from what we
		 * need here. However, LLVM also assumes that ffs(x) is
		 * in [0, 31], but GLSL expects that ffs(0) = -1, so
		 * a conditional assignment to handle 0 is still required.
		 *
		 * The hardware already implements the correct behavior.
		 */
		ctx->i1true,
	};

	LLVMValueRef lsb = ac_build_intrinsic(ctx, intrin_name, type,
					      params, 2,
					      AC_FUNC_ATTR_READNONE);

	if (src0_bitsize == 64) {
		lsb = LLVMBuildTrunc(ctx->builder, lsb, ctx->i32, "");
	}

	/* TODO: We need an intrinsic to skip this conditional. */
	/* Check for zero: */
	return LLVMBuildSelect(ctx->builder, LLVMBuildICmp(ctx->builder,
							   LLVMIntEQ, src0,
							   zero, ""),
			       LLVMConstInt(ctx->i32, -1, 0), lsb, "");
}

LLVMTypeRef ac_array_in_const_addr_space(LLVMTypeRef elem_type)
{
	return LLVMPointerType(LLVMArrayType(elem_type, 0),
			       AC_ADDR_SPACE_CONST);
}

LLVMTypeRef ac_array_in_const32_addr_space(LLVMTypeRef elem_type)
{
	return LLVMPointerType(LLVMArrayType(elem_type, 0),
			       AC_ADDR_SPACE_CONST_32BIT);
}

static struct ac_llvm_flow *
get_current_flow(struct ac_llvm_context *ctx)
{
	if (ctx->flow_depth > 0)
		return &ctx->flow[ctx->flow_depth - 1];
	return NULL;
}

static struct ac_llvm_flow *
get_innermost_loop(struct ac_llvm_context *ctx)
{
	for (unsigned i = ctx->flow_depth; i > 0; --i) {
		if (ctx->flow[i - 1].loop_entry_block)
			return &ctx->flow[i - 1];
	}
	return NULL;
}

static struct ac_llvm_flow *
push_flow(struct ac_llvm_context *ctx)
{
	struct ac_llvm_flow *flow;

	if (ctx->flow_depth >= ctx->flow_depth_max) {
		unsigned new_max = MAX2(ctx->flow_depth << 1,
					AC_LLVM_INITIAL_CF_DEPTH);

		ctx->flow = realloc(ctx->flow, new_max * sizeof(*ctx->flow));
		ctx->flow_depth_max = new_max;
	}

	flow = &ctx->flow[ctx->flow_depth];
	ctx->flow_depth++;

	flow->next_block = NULL;
	flow->loop_entry_block = NULL;
	return flow;
}

static void set_basicblock_name(LLVMBasicBlockRef bb, const char *base,
				int label_id)
{
	char buf[32];
	snprintf(buf, sizeof(buf), "%s%d", base, label_id);
	LLVMSetValueName(LLVMBasicBlockAsValue(bb), buf);
}

/* Append a basic block at the level of the parent flow.
 */
static LLVMBasicBlockRef append_basic_block(struct ac_llvm_context *ctx,
					    const char *name)
{
	assert(ctx->flow_depth >= 1);

	if (ctx->flow_depth >= 2) {
		struct ac_llvm_flow *flow = &ctx->flow[ctx->flow_depth - 2];

		return LLVMInsertBasicBlockInContext(ctx->context,
						     flow->next_block, name);
	}

	LLVMValueRef main_fn =
		LLVMGetBasicBlockParent(LLVMGetInsertBlock(ctx->builder));
	return LLVMAppendBasicBlockInContext(ctx->context, main_fn, name);
}

/* Emit a branch to the given default target for the current block if
 * applicable -- that is, if the current block does not already contain a
 * branch from a break or continue.
 */
static void emit_default_branch(LLVMBuilderRef builder,
				LLVMBasicBlockRef target)
{
	if (!LLVMGetBasicBlockTerminator(LLVMGetInsertBlock(builder)))
		 LLVMBuildBr(builder, target);
}

void ac_build_bgnloop(struct ac_llvm_context *ctx, int label_id)
{
	struct ac_llvm_flow *flow = push_flow(ctx);
	flow->loop_entry_block = append_basic_block(ctx, "LOOP");
	flow->next_block = append_basic_block(ctx, "ENDLOOP");
	set_basicblock_name(flow->loop_entry_block, "loop", label_id);
	LLVMBuildBr(ctx->builder, flow->loop_entry_block);
	LLVMPositionBuilderAtEnd(ctx->builder, flow->loop_entry_block);
}

void ac_build_break(struct ac_llvm_context *ctx)
{
	struct ac_llvm_flow *flow = get_innermost_loop(ctx);
	LLVMBuildBr(ctx->builder, flow->next_block);
}

void ac_build_continue(struct ac_llvm_context *ctx)
{
	struct ac_llvm_flow *flow = get_innermost_loop(ctx);
	LLVMBuildBr(ctx->builder, flow->loop_entry_block);
}

void ac_build_else(struct ac_llvm_context *ctx, int label_id)
{
	struct ac_llvm_flow *current_branch = get_current_flow(ctx);
	LLVMBasicBlockRef endif_block;

	assert(!current_branch->loop_entry_block);

	endif_block = append_basic_block(ctx, "ENDIF");
	emit_default_branch(ctx->builder, endif_block);

	LLVMPositionBuilderAtEnd(ctx->builder, current_branch->next_block);
	set_basicblock_name(current_branch->next_block, "else", label_id);

	current_branch->next_block = endif_block;
}

void ac_build_endif(struct ac_llvm_context *ctx, int label_id)
{
	struct ac_llvm_flow *current_branch = get_current_flow(ctx);

	assert(!current_branch->loop_entry_block);

	emit_default_branch(ctx->builder, current_branch->next_block);
	LLVMPositionBuilderAtEnd(ctx->builder, current_branch->next_block);
	set_basicblock_name(current_branch->next_block, "endif", label_id);

	ctx->flow_depth--;
}

void ac_build_endloop(struct ac_llvm_context *ctx, int label_id)
{
	struct ac_llvm_flow *current_loop = get_current_flow(ctx);

	assert(current_loop->loop_entry_block);

	emit_default_branch(ctx->builder, current_loop->loop_entry_block);

	LLVMPositionBuilderAtEnd(ctx->builder, current_loop->next_block);
	set_basicblock_name(current_loop->next_block, "endloop", label_id);
	ctx->flow_depth--;
}

void ac_build_ifcc(struct ac_llvm_context *ctx, LLVMValueRef cond, int label_id)
{
	struct ac_llvm_flow *flow = push_flow(ctx);
	LLVMBasicBlockRef if_block;

	if_block = append_basic_block(ctx, "IF");
	flow->next_block = append_basic_block(ctx, "ELSE");
	set_basicblock_name(if_block, "if", label_id);
	LLVMBuildCondBr(ctx->builder, cond, if_block, flow->next_block);
	LLVMPositionBuilderAtEnd(ctx->builder, if_block);
}

void ac_build_if(struct ac_llvm_context *ctx, LLVMValueRef value,
		 int label_id)
{
	LLVMValueRef cond = LLVMBuildFCmp(ctx->builder, LLVMRealUNE,
					  value, ctx->f32_0, "");
	ac_build_ifcc(ctx, cond, label_id);
}

void ac_build_uif(struct ac_llvm_context *ctx, LLVMValueRef value,
		  int label_id)
{
	LLVMValueRef cond = LLVMBuildICmp(ctx->builder, LLVMIntNE,
					  ac_to_integer(ctx, value),
					  ctx->i32_0, "");
	ac_build_ifcc(ctx, cond, label_id);
}

LLVMValueRef ac_build_alloca_undef(struct ac_llvm_context *ac, LLVMTypeRef type,
			     const char *name)
{
	LLVMBuilderRef builder = ac->builder;
	LLVMBasicBlockRef current_block = LLVMGetInsertBlock(builder);
	LLVMValueRef function = LLVMGetBasicBlockParent(current_block);
	LLVMBasicBlockRef first_block = LLVMGetEntryBasicBlock(function);
	LLVMValueRef first_instr = LLVMGetFirstInstruction(first_block);
	LLVMBuilderRef first_builder = LLVMCreateBuilderInContext(ac->context);
	LLVMValueRef res;

	if (first_instr) {
		LLVMPositionBuilderBefore(first_builder, first_instr);
	} else {
		LLVMPositionBuilderAtEnd(first_builder, first_block);
	}

	res = LLVMBuildAlloca(first_builder, type, name);
	LLVMDisposeBuilder(first_builder);
	return res;
}

LLVMValueRef ac_build_alloca(struct ac_llvm_context *ac,
				   LLVMTypeRef type, const char *name)
{
	LLVMValueRef ptr = ac_build_alloca_undef(ac, type, name);
	LLVMBuildStore(ac->builder, LLVMConstNull(type), ptr);
	return ptr;
}

LLVMValueRef ac_cast_ptr(struct ac_llvm_context *ctx, LLVMValueRef ptr,
                         LLVMTypeRef type)
{
	int addr_space = LLVMGetPointerAddressSpace(LLVMTypeOf(ptr));
	return LLVMBuildBitCast(ctx->builder, ptr,
	                        LLVMPointerType(type, addr_space), "");
}

LLVMValueRef ac_trim_vector(struct ac_llvm_context *ctx, LLVMValueRef value,
			    unsigned count)
{
	unsigned num_components = ac_get_llvm_num_components(value);
	if (count == num_components)
		return value;

	LLVMValueRef masks[MAX2(count, 2)];
	masks[0] = ctx->i32_0;
	masks[1] = ctx->i32_1;
	for (unsigned i = 2; i < count; i++)
		masks[i] = LLVMConstInt(ctx->i32, i, false);

	if (count == 1)
		return LLVMBuildExtractElement(ctx->builder, value, masks[0],
		                               "");

	LLVMValueRef swizzle = LLVMConstVector(masks, count);
	return LLVMBuildShuffleVector(ctx->builder, value, value, swizzle, "");
}

LLVMValueRef ac_unpack_param(struct ac_llvm_context *ctx, LLVMValueRef param,
			     unsigned rshift, unsigned bitwidth)
{
	LLVMValueRef value = param;
	if (rshift)
		value = LLVMBuildLShr(ctx->builder, value,
				      LLVMConstInt(ctx->i32, rshift, false), "");

	if (rshift + bitwidth < 32) {
		unsigned mask = (1 << bitwidth) - 1;
		value = LLVMBuildAnd(ctx->builder, value,
				     LLVMConstInt(ctx->i32, mask, false), "");
	}
	return value;
}

/* Adjust the sample index according to FMASK.
 *
 * For uncompressed MSAA surfaces, FMASK should return 0x76543210,
 * which is the identity mapping. Each nibble says which physical sample
 * should be fetched to get that sample.
 *
 * For example, 0x11111100 means there are only 2 samples stored and
 * the second sample covers 3/4 of the pixel. When reading samples 0
 * and 1, return physical sample 0 (determined by the first two 0s
 * in FMASK), otherwise return physical sample 1.
 *
 * The sample index should be adjusted as follows:
 *   addr[sample_index] = (fmask >> (addr[sample_index] * 4)) & 0xF;
 */
void ac_apply_fmask_to_sample(struct ac_llvm_context *ac, LLVMValueRef fmask,
			      LLVMValueRef *addr, bool is_array_tex)
{
	struct ac_image_args fmask_load = {};
	fmask_load.opcode = ac_image_load;
	fmask_load.resource = fmask;
	fmask_load.dmask = 0xf;
	fmask_load.dim = is_array_tex ? ac_image_2darray : ac_image_2d;

	fmask_load.coords[0] = addr[0];
	fmask_load.coords[1] = addr[1];
	if (is_array_tex)
		fmask_load.coords[2] = addr[2];

	LLVMValueRef fmask_value = ac_build_image_opcode(ac, &fmask_load);
	fmask_value = LLVMBuildExtractElement(ac->builder, fmask_value,
					      ac->i32_0, "");

	/* Apply the formula. */
	unsigned sample_chan = is_array_tex ? 3 : 2;
	LLVMValueRef final_sample;
	final_sample = LLVMBuildMul(ac->builder, addr[sample_chan],
				    LLVMConstInt(ac->i32, 4, 0), "");
	final_sample = LLVMBuildLShr(ac->builder, fmask_value, final_sample, "");
	/* Mask the sample index by 0x7, because 0x8 means an unknown value
	 * with EQAA, so those will map to 0. */
	final_sample = LLVMBuildAnd(ac->builder, final_sample,
				    LLVMConstInt(ac->i32, 0x7, 0), "");

	/* Don't rewrite the sample index if WORD1.DATA_FORMAT of the FMASK
	 * resource descriptor is 0 (invalid).
	 */
	LLVMValueRef tmp;
	tmp = LLVMBuildBitCast(ac->builder, fmask, ac->v8i32, "");
	tmp = LLVMBuildExtractElement(ac->builder, tmp, ac->i32_1, "");
	tmp = LLVMBuildICmp(ac->builder, LLVMIntNE, tmp, ac->i32_0, "");

	/* Replace the MSAA sample index. */
	addr[sample_chan] = LLVMBuildSelect(ac->builder, tmp, final_sample,
					    addr[sample_chan], "");
}

static LLVMValueRef
_ac_build_readlane(struct ac_llvm_context *ctx, LLVMValueRef src, LLVMValueRef lane)
{
	ac_build_optimization_barrier(ctx, &src);
	return ac_build_intrinsic(ctx,
			lane == NULL ? "llvm.amdgcn.readfirstlane" : "llvm.amdgcn.readlane",
			LLVMTypeOf(src), (LLVMValueRef []) {
			src, lane },
			lane == NULL ? 1 : 2,
			AC_FUNC_ATTR_READNONE |
			AC_FUNC_ATTR_CONVERGENT);
}

/**
 * Builds the "llvm.amdgcn.readlane" or "llvm.amdgcn.readfirstlane" intrinsic.
 * @param ctx
 * @param src
 * @param lane - id of the lane or NULL for the first active lane
 * @return value of the lane
 */
LLVMValueRef
ac_build_readlane(struct ac_llvm_context *ctx, LLVMValueRef src, LLVMValueRef lane)
{
	LLVMTypeRef src_type = LLVMTypeOf(src);
	src = ac_to_integer(ctx, src);
	unsigned bits = LLVMGetIntTypeWidth(LLVMTypeOf(src));
	LLVMValueRef ret;

	if (bits == 32) {
		ret = _ac_build_readlane(ctx, src, lane);
	} else {
		assert(bits % 32 == 0);
		LLVMTypeRef vec_type = LLVMVectorType(ctx->i32, bits / 32);
		LLVMValueRef src_vector =
			LLVMBuildBitCast(ctx->builder, src, vec_type, "");
		ret = LLVMGetUndef(vec_type);
		for (unsigned i = 0; i < bits / 32; i++) {
			src = LLVMBuildExtractElement(ctx->builder, src_vector,
						LLVMConstInt(ctx->i32, i, 0), "");
			LLVMValueRef ret_comp = _ac_build_readlane(ctx, src, lane);
			ret = LLVMBuildInsertElement(ctx->builder, ret, ret_comp,
						LLVMConstInt(ctx->i32, i, 0), "");
		}
	}
	return LLVMBuildBitCast(ctx->builder, ret, src_type, "");
}

LLVMValueRef
ac_build_writelane(struct ac_llvm_context *ctx, LLVMValueRef src, LLVMValueRef value, LLVMValueRef lane)
{
	/* TODO: Use the actual instruction when LLVM adds an intrinsic for it.
	 */
	LLVMValueRef pred = LLVMBuildICmp(ctx->builder, LLVMIntEQ, lane,
					  ac_get_thread_id(ctx), "");
	return LLVMBuildSelect(ctx->builder, pred, value, src, "");
}

LLVMValueRef
ac_build_mbcnt(struct ac_llvm_context *ctx, LLVMValueRef mask)
{
	LLVMValueRef mask_vec = LLVMBuildBitCast(ctx->builder, mask,
						 LLVMVectorType(ctx->i32, 2),
						 "");
	LLVMValueRef mask_lo = LLVMBuildExtractElement(ctx->builder, mask_vec,
						       ctx->i32_0, "");
	LLVMValueRef mask_hi = LLVMBuildExtractElement(ctx->builder, mask_vec,
						       ctx->i32_1, "");
	LLVMValueRef val =
		ac_build_intrinsic(ctx, "llvm.amdgcn.mbcnt.lo", ctx->i32,
				   (LLVMValueRef []) { mask_lo, ctx->i32_0 },
				   2, AC_FUNC_ATTR_READNONE);
	val = ac_build_intrinsic(ctx, "llvm.amdgcn.mbcnt.hi", ctx->i32,
				 (LLVMValueRef []) { mask_hi, val },
				 2, AC_FUNC_ATTR_READNONE);
	return val;
}

enum dpp_ctrl {
	_dpp_quad_perm = 0x000,
	_dpp_row_sl = 0x100,
	_dpp_row_sr = 0x110,
	_dpp_row_rr = 0x120,
	dpp_wf_sl1 = 0x130,
	dpp_wf_rl1 = 0x134,
	dpp_wf_sr1 = 0x138,
	dpp_wf_rr1 = 0x13C,
	dpp_row_mirror = 0x140,
	dpp_row_half_mirror = 0x141,
	dpp_row_bcast15 = 0x142,
	dpp_row_bcast31 = 0x143
};

static inline enum dpp_ctrl
dpp_quad_perm(unsigned lane0, unsigned lane1, unsigned lane2, unsigned lane3)
{
	assert(lane0 < 4 && lane1 < 4 && lane2 < 4 && lane3 < 4);
	return _dpp_quad_perm | lane0 | (lane1 << 2) | (lane2 << 4) | (lane3 << 6);
}

static inline enum dpp_ctrl
dpp_row_sl(unsigned amount)
{
	assert(amount > 0 && amount < 16);
	return _dpp_row_sl | amount;
}

static inline enum dpp_ctrl
dpp_row_sr(unsigned amount)
{
	assert(amount > 0 && amount < 16);
	return _dpp_row_sr | amount;
}

static LLVMValueRef
_ac_build_dpp(struct ac_llvm_context *ctx, LLVMValueRef old, LLVMValueRef src,
	      enum dpp_ctrl dpp_ctrl, unsigned row_mask, unsigned bank_mask,
	      bool bound_ctrl)
{
	return ac_build_intrinsic(ctx, "llvm.amdgcn.update.dpp.i32",
					LLVMTypeOf(old),
					(LLVMValueRef[]) {
						old, src,
						LLVMConstInt(ctx->i32, dpp_ctrl, 0),
						LLVMConstInt(ctx->i32, row_mask, 0),
						LLVMConstInt(ctx->i32, bank_mask, 0),
						LLVMConstInt(ctx->i1, bound_ctrl, 0) },
					6, AC_FUNC_ATTR_READNONE | AC_FUNC_ATTR_CONVERGENT);
}

static LLVMValueRef
ac_build_dpp(struct ac_llvm_context *ctx, LLVMValueRef old, LLVMValueRef src,
	     enum dpp_ctrl dpp_ctrl, unsigned row_mask, unsigned bank_mask,
	     bool bound_ctrl)
{
	LLVMTypeRef src_type = LLVMTypeOf(src);
	src = ac_to_integer(ctx, src);
	old = ac_to_integer(ctx, old);
	unsigned bits = LLVMGetIntTypeWidth(LLVMTypeOf(src));
	LLVMValueRef ret;
	if (bits == 32) {
		ret = _ac_build_dpp(ctx, old, src, dpp_ctrl, row_mask,
				    bank_mask, bound_ctrl);
	} else {
		assert(bits % 32 == 0);
		LLVMTypeRef vec_type = LLVMVectorType(ctx->i32, bits / 32);
		LLVMValueRef src_vector =
			LLVMBuildBitCast(ctx->builder, src, vec_type, "");
		LLVMValueRef old_vector =
			LLVMBuildBitCast(ctx->builder, old, vec_type, "");
		ret = LLVMGetUndef(vec_type);
		for (unsigned i = 0; i < bits / 32; i++) {
			src = LLVMBuildExtractElement(ctx->builder, src_vector,
						      LLVMConstInt(ctx->i32, i,
								   0), "");
			old = LLVMBuildExtractElement(ctx->builder, old_vector,
						      LLVMConstInt(ctx->i32, i,
								   0), "");
			LLVMValueRef ret_comp = _ac_build_dpp(ctx, old, src,
							      dpp_ctrl,
							      row_mask,
							      bank_mask,
							      bound_ctrl);
			ret = LLVMBuildInsertElement(ctx->builder, ret,
						     ret_comp,
						     LLVMConstInt(ctx->i32, i,
								  0), "");
		}
	}
	return LLVMBuildBitCast(ctx->builder, ret, src_type, "");
}

static inline unsigned
ds_pattern_bitmode(unsigned and_mask, unsigned or_mask, unsigned xor_mask)
{
	assert(and_mask < 32 && or_mask < 32 && xor_mask < 32);
	return and_mask | (or_mask << 5) | (xor_mask << 10);
}

static LLVMValueRef
_ac_build_ds_swizzle(struct ac_llvm_context *ctx, LLVMValueRef src, unsigned mask)
{
	return ac_build_intrinsic(ctx, "llvm.amdgcn.ds.swizzle",
				   LLVMTypeOf(src), (LLVMValueRef []) {
					src, LLVMConstInt(ctx->i32, mask, 0) },
				   2, AC_FUNC_ATTR_READNONE | AC_FUNC_ATTR_CONVERGENT);
}

LLVMValueRef
ac_build_ds_swizzle(struct ac_llvm_context *ctx, LLVMValueRef src, unsigned mask)
{
	LLVMTypeRef src_type = LLVMTypeOf(src);
	src = ac_to_integer(ctx, src);
	unsigned bits = LLVMGetIntTypeWidth(LLVMTypeOf(src));
	LLVMValueRef ret;
	if (bits == 32) {
		ret = _ac_build_ds_swizzle(ctx, src, mask);
	} else {
		assert(bits % 32 == 0);
		LLVMTypeRef vec_type = LLVMVectorType(ctx->i32, bits / 32);
		LLVMValueRef src_vector =
			LLVMBuildBitCast(ctx->builder, src, vec_type, "");
		ret = LLVMGetUndef(vec_type);
		for (unsigned i = 0; i < bits / 32; i++) {
			src = LLVMBuildExtractElement(ctx->builder, src_vector,
						      LLVMConstInt(ctx->i32, i,
								   0), "");
			LLVMValueRef ret_comp = _ac_build_ds_swizzle(ctx, src,
								     mask);
			ret = LLVMBuildInsertElement(ctx->builder, ret,
						     ret_comp,
						     LLVMConstInt(ctx->i32, i,
								  0), "");
		}
	}
	return LLVMBuildBitCast(ctx->builder, ret, src_type, "");
}

static LLVMValueRef
ac_build_wwm(struct ac_llvm_context *ctx, LLVMValueRef src)
{
	char name[32], type[8];
	ac_build_type_name_for_intr(LLVMTypeOf(src), type, sizeof(type));
	snprintf(name, sizeof(name), "llvm.amdgcn.wwm.%s", type);
	return ac_build_intrinsic(ctx, name, LLVMTypeOf(src),
				  (LLVMValueRef []) { src }, 1,
				  AC_FUNC_ATTR_READNONE);
}

static LLVMValueRef
ac_build_set_inactive(struct ac_llvm_context *ctx, LLVMValueRef src,
		      LLVMValueRef inactive)
{
	char name[33], type[8];
	LLVMTypeRef src_type = LLVMTypeOf(src);
	src = ac_to_integer(ctx, src);
	inactive = ac_to_integer(ctx, inactive);
	ac_build_type_name_for_intr(LLVMTypeOf(src), type, sizeof(type));
	snprintf(name, sizeof(name), "llvm.amdgcn.set.inactive.%s", type);
	LLVMValueRef ret =
		ac_build_intrinsic(ctx, name,
					LLVMTypeOf(src), (LLVMValueRef []) {
					src, inactive }, 2,
					AC_FUNC_ATTR_READNONE |
					AC_FUNC_ATTR_CONVERGENT);
	return LLVMBuildBitCast(ctx->builder, ret, src_type, "");
}

static LLVMValueRef
get_reduction_identity(struct ac_llvm_context *ctx, nir_op op, unsigned type_size)
{
	if (type_size == 4) {
		switch (op) {
		case nir_op_iadd: return ctx->i32_0;
		case nir_op_fadd: return ctx->f32_0;
		case nir_op_imul: return ctx->i32_1;
		case nir_op_fmul: return ctx->f32_1;
		case nir_op_imin: return LLVMConstInt(ctx->i32, INT32_MAX, 0);
		case nir_op_umin: return LLVMConstInt(ctx->i32, UINT32_MAX, 0);
		case nir_op_fmin: return LLVMConstReal(ctx->f32, INFINITY);
		case nir_op_imax: return LLVMConstInt(ctx->i32, INT32_MIN, 0);
		case nir_op_umax: return ctx->i32_0;
		case nir_op_fmax: return LLVMConstReal(ctx->f32, -INFINITY);
		case nir_op_iand: return LLVMConstInt(ctx->i32, -1, 0);
		case nir_op_ior: return ctx->i32_0;
		case nir_op_ixor: return ctx->i32_0;
		default:
			unreachable("bad reduction intrinsic");
		}
	} else { /* type_size == 64bit */
		switch (op) {
		case nir_op_iadd: return ctx->i64_0;
		case nir_op_fadd: return ctx->f64_0;
		case nir_op_imul: return ctx->i64_1;
		case nir_op_fmul: return ctx->f64_1;
		case nir_op_imin: return LLVMConstInt(ctx->i64, INT64_MAX, 0);
		case nir_op_umin: return LLVMConstInt(ctx->i64, UINT64_MAX, 0);
		case nir_op_fmin: return LLVMConstReal(ctx->f64, INFINITY);
		case nir_op_imax: return LLVMConstInt(ctx->i64, INT64_MIN, 0);
		case nir_op_umax: return ctx->i64_0;
		case nir_op_fmax: return LLVMConstReal(ctx->f64, -INFINITY);
		case nir_op_iand: return LLVMConstInt(ctx->i64, -1, 0);
		case nir_op_ior: return ctx->i64_0;
		case nir_op_ixor: return ctx->i64_0;
		default:
			unreachable("bad reduction intrinsic");
		}
	}
}

static LLVMValueRef
ac_build_alu_op(struct ac_llvm_context *ctx, LLVMValueRef lhs, LLVMValueRef rhs, nir_op op)
{
	bool _64bit = ac_get_type_size(LLVMTypeOf(lhs)) == 8;
	switch (op) {
	case nir_op_iadd: return LLVMBuildAdd(ctx->builder, lhs, rhs, "");
	case nir_op_fadd: return LLVMBuildFAdd(ctx->builder, lhs, rhs, "");
	case nir_op_imul: return LLVMBuildMul(ctx->builder, lhs, rhs, "");
	case nir_op_fmul: return LLVMBuildFMul(ctx->builder, lhs, rhs, "");
	case nir_op_imin: return LLVMBuildSelect(ctx->builder,
					LLVMBuildICmp(ctx->builder, LLVMIntSLT, lhs, rhs, ""),
					lhs, rhs, "");
	case nir_op_umin: return LLVMBuildSelect(ctx->builder,
					LLVMBuildICmp(ctx->builder, LLVMIntULT, lhs, rhs, ""),
					lhs, rhs, "");
	case nir_op_fmin: return ac_build_intrinsic(ctx,
					_64bit ? "llvm.minnum.f64" : "llvm.minnum.f32",
					_64bit ? ctx->f64 : ctx->f32,
					(LLVMValueRef[]){lhs, rhs}, 2, AC_FUNC_ATTR_READNONE);
	case nir_op_imax: return LLVMBuildSelect(ctx->builder,
					LLVMBuildICmp(ctx->builder, LLVMIntSGT, lhs, rhs, ""),
					lhs, rhs, "");
	case nir_op_umax: return LLVMBuildSelect(ctx->builder,
					LLVMBuildICmp(ctx->builder, LLVMIntUGT, lhs, rhs, ""),
					lhs, rhs, "");
	case nir_op_fmax: return ac_build_intrinsic(ctx,
					_64bit ? "llvm.maxnum.f64" : "llvm.maxnum.f32",
					_64bit ? ctx->f64 : ctx->f32,
					(LLVMValueRef[]){lhs, rhs}, 2, AC_FUNC_ATTR_READNONE);
	case nir_op_iand: return LLVMBuildAnd(ctx->builder, lhs, rhs, "");
	case nir_op_ior: return LLVMBuildOr(ctx->builder, lhs, rhs, "");
	case nir_op_ixor: return LLVMBuildXor(ctx->builder, lhs, rhs, "");
	default:
		unreachable("bad reduction intrinsic");
	}
}

/**
 * \param maxprefix specifies that the result only needs to be correct for a
 *     prefix of this many threads
 *
 * TODO: add inclusive and excluse scan functions for SI chip class.
 */
static LLVMValueRef
ac_build_scan(struct ac_llvm_context *ctx, nir_op op, LLVMValueRef src, LLVMValueRef identity,
	      unsigned maxprefix)
{
	LLVMValueRef result, tmp;
	result = src;
	if (maxprefix <= 1)
		return result;
	tmp = ac_build_dpp(ctx, identity, src, dpp_row_sr(1), 0xf, 0xf, false);
	result = ac_build_alu_op(ctx, result, tmp, op);
	if (maxprefix <= 2)
		return result;
	tmp = ac_build_dpp(ctx, identity, src, dpp_row_sr(2), 0xf, 0xf, false);
	result = ac_build_alu_op(ctx, result, tmp, op);
	if (maxprefix <= 3)
		return result;
	tmp = ac_build_dpp(ctx, identity, src, dpp_row_sr(3), 0xf, 0xf, false);
	result = ac_build_alu_op(ctx, result, tmp, op);
	if (maxprefix <= 4)
		return result;
	tmp = ac_build_dpp(ctx, identity, result, dpp_row_sr(4), 0xf, 0xe, false);
	result = ac_build_alu_op(ctx, result, tmp, op);
	if (maxprefix <= 8)
		return result;
	tmp = ac_build_dpp(ctx, identity, result, dpp_row_sr(8), 0xf, 0xc, false);
	result = ac_build_alu_op(ctx, result, tmp, op);
	if (maxprefix <= 16)
		return result;
	tmp = ac_build_dpp(ctx, identity, result, dpp_row_bcast15, 0xa, 0xf, false);
	result = ac_build_alu_op(ctx, result, tmp, op);
	if (maxprefix <= 32)
		return result;
	tmp = ac_build_dpp(ctx, identity, result, dpp_row_bcast31, 0xc, 0xf, false);
	result = ac_build_alu_op(ctx, result, tmp, op);
	return result;
}

LLVMValueRef
ac_build_inclusive_scan(struct ac_llvm_context *ctx, LLVMValueRef src, nir_op op)
{
	LLVMValueRef result;

	if (LLVMTypeOf(src) == ctx->i1 && op == nir_op_iadd) {
		LLVMBuilderRef builder = ctx->builder;
		src = LLVMBuildZExt(builder, src, ctx->i32, "");
		result = ac_build_ballot(ctx, src);
		result = ac_build_mbcnt(ctx, result);
		result = LLVMBuildAdd(builder, result, src, "");
		return result;
	}

	ac_build_optimization_barrier(ctx, &src);

	LLVMValueRef identity =
		get_reduction_identity(ctx, op, ac_get_type_size(LLVMTypeOf(src)));
	result = LLVMBuildBitCast(ctx->builder, ac_build_set_inactive(ctx, src, identity),
				  LLVMTypeOf(identity), "");
	result = ac_build_scan(ctx, op, result, identity, 64);

	return ac_build_wwm(ctx, result);
}

LLVMValueRef
ac_build_exclusive_scan(struct ac_llvm_context *ctx, LLVMValueRef src, nir_op op)
{
	LLVMValueRef result;

	if (LLVMTypeOf(src) == ctx->i1 && op == nir_op_iadd) {
		LLVMBuilderRef builder = ctx->builder;
		src = LLVMBuildZExt(builder, src, ctx->i32, "");
		result = ac_build_ballot(ctx, src);
		result = ac_build_mbcnt(ctx, result);
		return result;
	}

	ac_build_optimization_barrier(ctx, &src);

	LLVMValueRef identity =
		get_reduction_identity(ctx, op, ac_get_type_size(LLVMTypeOf(src)));
	result = LLVMBuildBitCast(ctx->builder, ac_build_set_inactive(ctx, src, identity),
				  LLVMTypeOf(identity), "");
	result = ac_build_dpp(ctx, identity, result, dpp_wf_sr1, 0xf, 0xf, false);
	result = ac_build_scan(ctx, op, result, identity, 64);

	return ac_build_wwm(ctx, result);
}

LLVMValueRef
ac_build_reduce(struct ac_llvm_context *ctx, LLVMValueRef src, nir_op op, unsigned cluster_size)
{
	if (cluster_size == 1) return src;
	ac_build_optimization_barrier(ctx, &src);
	LLVMValueRef result, swap;
	LLVMValueRef identity = get_reduction_identity(ctx, op,
								ac_get_type_size(LLVMTypeOf(src)));
	result = LLVMBuildBitCast(ctx->builder,
								ac_build_set_inactive(ctx, src, identity),
								LLVMTypeOf(identity), "");
	swap = ac_build_quad_swizzle(ctx, result, 1, 0, 3, 2);
	result = ac_build_alu_op(ctx, result, swap, op);
	if (cluster_size == 2) return ac_build_wwm(ctx, result);

	swap = ac_build_quad_swizzle(ctx, result, 2, 3, 0, 1);
	result = ac_build_alu_op(ctx, result, swap, op);
	if (cluster_size == 4) return ac_build_wwm(ctx, result);

	if (ctx->chip_class >= VI)
		swap = ac_build_dpp(ctx, identity, result, dpp_row_half_mirror, 0xf, 0xf, false);
	else
		swap = ac_build_ds_swizzle(ctx, result, ds_pattern_bitmode(0x1f, 0, 0x04));
	result = ac_build_alu_op(ctx, result, swap, op);
	if (cluster_size == 8) return ac_build_wwm(ctx, result);

	if (ctx->chip_class >= VI)
		swap = ac_build_dpp(ctx, identity, result, dpp_row_mirror, 0xf, 0xf, false);
	else
		swap = ac_build_ds_swizzle(ctx, result, ds_pattern_bitmode(0x1f, 0, 0x08));
	result = ac_build_alu_op(ctx, result, swap, op);
	if (cluster_size == 16) return ac_build_wwm(ctx, result);

	if (ctx->chip_class >= VI && cluster_size != 32)
		swap = ac_build_dpp(ctx, identity, result, dpp_row_bcast15, 0xa, 0xf, false);
	else
		swap = ac_build_ds_swizzle(ctx, result, ds_pattern_bitmode(0x1f, 0, 0x10));
	result = ac_build_alu_op(ctx, result, swap, op);
	if (cluster_size == 32) return ac_build_wwm(ctx, result);

	if (ctx->chip_class >= VI) {
		swap = ac_build_dpp(ctx, identity, result, dpp_row_bcast31, 0xc, 0xf, false);
		result = ac_build_alu_op(ctx, result, swap, op);
		result = ac_build_readlane(ctx, result, LLVMConstInt(ctx->i32, 63, 0));
		return ac_build_wwm(ctx, result);
	} else {
		swap = ac_build_readlane(ctx, result, ctx->i32_0);
		result = ac_build_readlane(ctx, result, LLVMConstInt(ctx->i32, 32, 0));
		result = ac_build_alu_op(ctx, result, swap, op);
		return ac_build_wwm(ctx, result);
	}
}

/**
 * "Top half" of a scan that reduces per-wave values across an entire
 * workgroup.
 *
 * The source value must be present in the highest lane of the wave, and the
 * highest lane must be live.
 */
void
ac_build_wg_wavescan_top(struct ac_llvm_context *ctx, struct ac_wg_scan *ws)
{
	if (ws->maxwaves <= 1)
		return;

	const LLVMValueRef i32_63 = LLVMConstInt(ctx->i32, 63, false);
	LLVMBuilderRef builder = ctx->builder;
	LLVMValueRef tid = ac_get_thread_id(ctx);
	LLVMValueRef tmp;

	tmp = LLVMBuildICmp(builder, LLVMIntEQ, tid, i32_63, "");
	ac_build_ifcc(ctx, tmp, 1000);
	LLVMBuildStore(builder, ws->src, LLVMBuildGEP(builder, ws->scratch, &ws->waveidx, 1, ""));
	ac_build_endif(ctx, 1000);
}

/**
 * "Bottom half" of a scan that reduces per-wave values across an entire
 * workgroup.
 *
 * The caller must place a barrier between the top and bottom halves.
 */
void
ac_build_wg_wavescan_bottom(struct ac_llvm_context *ctx, struct ac_wg_scan *ws)
{
	const LLVMTypeRef type = LLVMTypeOf(ws->src);
	const LLVMValueRef identity =
		get_reduction_identity(ctx, ws->op, ac_get_type_size(type));

	if (ws->maxwaves <= 1) {
		ws->result_reduce = ws->src;
		ws->result_inclusive = ws->src;
		ws->result_exclusive = identity;
		return;
	}
	assert(ws->maxwaves <= 32);

	LLVMBuilderRef builder = ctx->builder;
	LLVMValueRef tid = ac_get_thread_id(ctx);
	LLVMBasicBlockRef bbs[2];
	LLVMValueRef phivalues_scan[2];
	LLVMValueRef tmp, tmp2;

	bbs[0] = LLVMGetInsertBlock(builder);
	phivalues_scan[0] = LLVMGetUndef(type);

	if (ws->enable_reduce)
		tmp = LLVMBuildICmp(builder, LLVMIntULT, tid, ws->numwaves, "");
	else if (ws->enable_inclusive)
		tmp = LLVMBuildICmp(builder, LLVMIntULE, tid, ws->waveidx, "");
	else
		tmp = LLVMBuildICmp(builder, LLVMIntULT, tid, ws->waveidx, "");
	ac_build_ifcc(ctx, tmp, 1001);
	{
		tmp = LLVMBuildLoad(builder, LLVMBuildGEP(builder, ws->scratch, &tid, 1, ""), "");

		ac_build_optimization_barrier(ctx, &tmp);

		bbs[1] = LLVMGetInsertBlock(builder);
		phivalues_scan[1] = ac_build_scan(ctx, ws->op, tmp, identity, ws->maxwaves);
	}
	ac_build_endif(ctx, 1001);

	const LLVMValueRef scan = ac_build_phi(ctx, type, 2, phivalues_scan, bbs);

	if (ws->enable_reduce) {
		tmp = LLVMBuildSub(builder, ws->numwaves, ctx->i32_1, "");
		ws->result_reduce = ac_build_readlane(ctx, scan, tmp);
	}
	if (ws->enable_inclusive)
		ws->result_inclusive = ac_build_readlane(ctx, scan, ws->waveidx);
	if (ws->enable_exclusive) {
		tmp = LLVMBuildSub(builder, ws->waveidx, ctx->i32_1, "");
		tmp = ac_build_readlane(ctx, scan, tmp);
		tmp2 = LLVMBuildICmp(builder, LLVMIntEQ, ws->waveidx, ctx->i32_0, "");
		ws->result_exclusive = LLVMBuildSelect(builder, tmp2, identity, tmp, "");
	}
}

/**
 * Inclusive scan of a per-wave value across an entire workgroup.
 *
 * This implies an s_barrier instruction.
 *
 * Unlike ac_build_inclusive_scan, the caller \em must ensure that all threads
 * of the workgroup are live. (This requirement cannot easily be relaxed in a
 * useful manner because of the barrier in the algorithm.)
 */
void
ac_build_wg_wavescan(struct ac_llvm_context *ctx, struct ac_wg_scan *ws)
{
	ac_build_wg_wavescan_top(ctx, ws);
	ac_build_s_barrier(ctx);
	ac_build_wg_wavescan_bottom(ctx, ws);
}

/**
 * "Top half" of a scan that reduces per-thread values across an entire
 * workgroup.
 *
 * All lanes must be active when this code runs.
 */
void
ac_build_wg_scan_top(struct ac_llvm_context *ctx, struct ac_wg_scan *ws)
{
	if (ws->enable_exclusive) {
		ws->extra = ac_build_exclusive_scan(ctx, ws->src, ws->op);
		if (LLVMTypeOf(ws->src) == ctx->i1 && ws->op == nir_op_iadd)
			ws->src = LLVMBuildZExt(ctx->builder, ws->src, ctx->i32, "");
		ws->src = ac_build_alu_op(ctx, ws->extra, ws->src, ws->op);
	} else {
		ws->src = ac_build_inclusive_scan(ctx, ws->src, ws->op);
	}

	bool enable_inclusive = ws->enable_inclusive;
	bool enable_exclusive = ws->enable_exclusive;
	ws->enable_inclusive = false;
	ws->enable_exclusive = ws->enable_exclusive || enable_inclusive;
	ac_build_wg_wavescan_top(ctx, ws);
	ws->enable_inclusive = enable_inclusive;
	ws->enable_exclusive = enable_exclusive;
}

/**
 * "Bottom half" of a scan that reduces per-thread values across an entire
 * workgroup.
 *
 * The caller must place a barrier between the top and bottom halves.
 */
void
ac_build_wg_scan_bottom(struct ac_llvm_context *ctx, struct ac_wg_scan *ws)
{
	bool enable_inclusive = ws->enable_inclusive;
	bool enable_exclusive = ws->enable_exclusive;
	ws->enable_inclusive = false;
	ws->enable_exclusive = ws->enable_exclusive || enable_inclusive;
	ac_build_wg_wavescan_bottom(ctx, ws);
	ws->enable_inclusive = enable_inclusive;
	ws->enable_exclusive = enable_exclusive;

	/* ws->result_reduce is already the correct value */
	if (ws->enable_inclusive)
		ws->result_inclusive = ac_build_alu_op(ctx, ws->result_exclusive, ws->src, ws->op);
	if (ws->enable_exclusive)
		ws->result_exclusive = ac_build_alu_op(ctx, ws->result_exclusive, ws->extra, ws->op);
}

/**
 * A scan that reduces per-thread values across an entire workgroup.
 *
 * The caller must ensure that all lanes are active when this code runs
 * (WWM is insufficient!), because there is an implied barrier.
 */
void
ac_build_wg_scan(struct ac_llvm_context *ctx, struct ac_wg_scan *ws)
{
	ac_build_wg_scan_top(ctx, ws);
	ac_build_s_barrier(ctx);
	ac_build_wg_scan_bottom(ctx, ws);
}

LLVMValueRef
ac_build_quad_swizzle(struct ac_llvm_context *ctx, LLVMValueRef src,
		unsigned lane0, unsigned lane1, unsigned lane2, unsigned lane3)
{
	unsigned mask = dpp_quad_perm(lane0, lane1, lane2, lane3);
	if (ctx->chip_class >= VI) {
		return ac_build_dpp(ctx, src, src, mask, 0xf, 0xf, false);
	} else {
		return ac_build_ds_swizzle(ctx, src, (1 << 15) | mask);
	}
}

LLVMValueRef
ac_build_shuffle(struct ac_llvm_context *ctx, LLVMValueRef src, LLVMValueRef index)
{
	index = LLVMBuildMul(ctx->builder, index, LLVMConstInt(ctx->i32, 4, 0), "");
	return ac_build_intrinsic(ctx,
		  "llvm.amdgcn.ds.bpermute", ctx->i32,
		  (LLVMValueRef []) {index, src}, 2,
		  AC_FUNC_ATTR_READNONE |
		  AC_FUNC_ATTR_CONVERGENT);
}