src/gallium/drivers/llvmpipe/lp_bld_flow.c

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/**
 * LLVM control flow build helpers.
 *
 * @author Jose Fonseca <jfonseca@vmware.com>
 */

#include "lp_bld_flow.h"



void
lp_build_loop_begin(LLVMBuilderRef builder,
                    LLVMValueRef start,
                    struct lp_build_loop_state *state)
{
   LLVMBasicBlockRef block = LLVMGetInsertBlock(builder);
   LLVMValueRef function = LLVMGetBasicBlockParent(block);

   state->block = LLVMAppendBasicBlock(function, "loop");

   LLVMBuildBr(builder, state->block);

   LLVMPositionBuilderAtEnd(builder, state->block);

   state->counter = LLVMBuildPhi(builder, LLVMTypeOf(start), "");

   LLVMAddIncoming(state->counter, &start, &block, 1);

}


void
lp_build_loop_end(LLVMBuilderRef builder,
                  LLVMValueRef end,
                  LLVMValueRef step,
                  struct lp_build_loop_state *state)
{
   LLVMBasicBlockRef block = LLVMGetInsertBlock(builder);
   LLVMValueRef function = LLVMGetBasicBlockParent(block);
   LLVMValueRef next;
   LLVMValueRef cond;
   LLVMBasicBlockRef after_block;

   if (!step)
      step = LLVMConstInt(LLVMTypeOf(end), 1, 0);

   next = LLVMBuildAdd(builder, state->counter, step, "");

   cond = LLVMBuildICmp(builder, LLVMIntNE, next, end, "");

   after_block = LLVMAppendBasicBlock(function, "");

   LLVMBuildCondBr(builder, cond, after_block, state->block);

   LLVMAddIncoming(state->counter, &next, &block, 1);

   LLVMPositionBuilderAtEnd(builder, after_block);
}