arch/X86/X86ATTInstPrinter.c

//===-- X86ATTInstPrinter.cpp - AT&T assembly instruction printing --------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file includes code for rendering MCInst instances as AT&T-style
// assembly.
//
//===----------------------------------------------------------------------===//

/* Capstone Disassembler Engine */
/* By Nguyen Anh Quynh <aquynh@gmail.com>, 2013> */

#include <ctype.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "../../utils.h"
#include "../../MCInst.h"
#include "../../SStream.h"
#include "../../MCRegisterInfo.h"
#include "mapping.h"

#define markup(x) ""


const char *X86ATT_getRegisterName(unsigned RegNo);

static void printMemReference(MCInst *MI, unsigned Op, SStream *O);

static void printopaquemem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "OPAQUE PTR ");
	printMemReference(MI, OpNo, O);
}

static void printi8mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "BYTE PTR ");
	printMemReference(MI, OpNo, O);
}

static void printi16mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "WORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printi32mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "DWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printi64mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "QWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printi128mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "XMMWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printi256mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "YMMWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printi512mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	printMemReference(MI, OpNo, O);
}

static void printf32mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "DWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printf64mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "QWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printf80mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "XWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printf128mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "XMMWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printf256mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	SStream_concat(O, "YMMWORD PTR ");
	printMemReference(MI, OpNo, O);
}

static void printf512mem(MCInst *MI, unsigned OpNo, SStream *O)
{
	printMemReference(MI, OpNo, O);
}

static void printMemOffset(MCInst *MI, unsigned Op, SStream *O)
{
	MCOperand *DispSpec = MCInst_getOperand(MI, Op);

	SStream_concat(O, "%s", markup("<mem:"));

	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].type = X86_OP_MEM;
	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.base = X86_REG_INVALID;
	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.index = X86_REG_INVALID;
	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.scale = 1;
	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.disp = 0;

	if (MCOperand_isImm(DispSpec)) {
		int64_t imm = MCOperand_getImm(DispSpec);
		MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.disp = imm;
		if (imm < 0)
			SStream_concat(O, "-0x%"PRIx64, -imm);
		else
			SStream_concat(O, "0x%"PRIx64, imm);
	}

	SStream_concat(O, "%s", markup(">"));

	MI->pub_insn.x86.op_count++;
}

static void printMemOffs8(MCInst *MI, unsigned OpNo, SStream *O)
{
	// If this has a segment register, print it.
	// this is a hack. will fix it later
	if (MI->pub_insn.x86.segment) {
		SStream_concat(O, "%%%s:", X86_reg_name(MI->pub_insn.x86.segment));
	}

	printMemOffset(MI, OpNo, O);
}

static void printMemOffs16(MCInst *MI, unsigned OpNo, SStream *O)
{
	// If this has a segment register, print it.
	// this is a hack. will fix it later
	if (MI->pub_insn.x86.segment) {
		SStream_concat(O, "%%%s:", X86_reg_name(MI->pub_insn.x86.segment));
	}

	printMemOffset(MI, OpNo, O);
}

static void printMemOffs32(MCInst *MI, unsigned OpNo, SStream *O)
{
	// If this has a segment register, print it.
	// this is a hack. will fix it later
	if (MI->pub_insn.x86.segment) {
		SStream_concat(O, "%%%s:", X86_reg_name(MI->pub_insn.x86.segment));
	}

	printMemOffset(MI, OpNo, O);
}

static void printMemOffs64(MCInst *MI, unsigned OpNo, SStream *O)
{
	printMemOffset(MI, OpNo, O);
}

static void printRegName(SStream *OS, unsigned RegNo);

static void printSSECC(MCInst *MI, unsigned Op, SStream *OS)
{
	int64_t Imm = MCOperand_getImm(MCInst_getOperand(MI, Op)) & 0xf;
	switch (Imm) {
		default: break;	// never reach
		case    0: SStream_concat(OS, "eq"); break;
		case    1: SStream_concat(OS, "lt"); break;
		case    2: SStream_concat(OS, "le"); break;
		case    3: SStream_concat(OS, "unord"); break;
		case    4: SStream_concat(OS, "neq"); break;
		case    5: SStream_concat(OS, "nlt"); break;
		case    6: SStream_concat(OS, "nle"); break;
		case    7: SStream_concat(OS, "ord"); break;
		case    8: SStream_concat(OS, "eq_uq"); break;
		case    9: SStream_concat(OS, "nge"); break;
		case  0xa: SStream_concat(OS, "ngt"); break;
		case  0xb: SStream_concat(OS, "false"); break;
		case  0xc: SStream_concat(OS, "neq_oq"); break;
		case  0xd: SStream_concat(OS, "ge"); break;
		case  0xe: SStream_concat(OS, "gt"); break;
		case  0xf: SStream_concat(OS, "true"); break;
	}
}

static void printAVXCC(MCInst *MI, unsigned Op, SStream *O)
{
	int64_t Imm = MCOperand_getImm(MCInst_getOperand(MI, Op)) & 0x1f;
	switch (Imm) {
		default: printf("Invalid avxcc argument!\n"); break;
		case    0: SStream_concat(O, "eq"); break;
		case    1: SStream_concat(O, "lt"); break;
		case    2: SStream_concat(O, "le"); break;
		case    3: SStream_concat(O, "unord"); break;
		case    4: SStream_concat(O, "neq"); break;
		case    5: SStream_concat(O, "nlt"); break;
		case    6: SStream_concat(O, "nle"); break;
		case    7: SStream_concat(O, "ord"); break;
		case    8: SStream_concat(O, "eq_uq"); break;
		case    9: SStream_concat(O, "nge"); break;
		case  0xa: SStream_concat(O, "ngt"); break;
		case  0xb: SStream_concat(O, "false"); break;
		case  0xc: SStream_concat(O, "neq_oq"); break;
		case  0xd: SStream_concat(O, "ge"); break;
		case  0xe: SStream_concat(O, "gt"); break;
		case  0xf: SStream_concat(O, "true"); break;
		case 0x10: SStream_concat(O, "eq_os"); break;
		case 0x11: SStream_concat(O, "lt_oq"); break;
		case 0x12: SStream_concat(O, "le_oq"); break;
		case 0x13: SStream_concat(O, "unord_s"); break;
		case 0x14: SStream_concat(O, "neq_us"); break;
		case 0x15: SStream_concat(O, "nlt_uq"); break;
		case 0x16: SStream_concat(O, "nle_uq"); break;
		case 0x17: SStream_concat(O, "ord_s"); break;
		case 0x18: SStream_concat(O, "eq_us"); break;
		case 0x19: SStream_concat(O, "nge_uq"); break;
		case 0x1a: SStream_concat(O, "ngt_uq"); break;
		case 0x1b: SStream_concat(O, "false_os"); break;
		case 0x1c: SStream_concat(O, "neq_os"); break;
		case 0x1d: SStream_concat(O, "ge_oq"); break;
		case 0x1e: SStream_concat(O, "gt_oq"); break;
		case 0x1f: SStream_concat(O, "true_us"); break;
	}
}

/// printPCRelImm - This is used to print an immediate value that ends up
/// being encoded as a pc-relative value (e.g. for jumps and calls).  These
/// print slightly differently than normal immediates.  For example, a $ is not
/// emitted.
static void printPCRelImm(MCInst *MI, unsigned OpNo, SStream *O)
{
	MCOperand *Op = MCInst_getOperand(MI, OpNo);
	if (MCOperand_isImm(Op)) {
		int64_t imm = MCOperand_getImm(Op) + MI->pub_insn.size + MI->pub_insn.address;
		if (imm < 0)
			SStream_concat(O, "-0x%"PRIx64, -imm);
		else
			SStream_concat(O, "0x%"PRIx64, imm);
		MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].type = X86_OP_IMM;
		MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].imm = imm;
		MI->pub_insn.x86.op_count++;
	}
}

static void printOperand(MCInst *MI, unsigned OpNo, SStream *O)
{
	MCOperand *Op  = MCInst_getOperand(MI, OpNo);
	if (MCOperand_isReg(Op)) {
		printRegName(O, MCOperand_getReg(Op));
		MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].type = X86_OP_REG;
		MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].reg = MCOperand_getReg(Op);
		MI->pub_insn.x86.op_count++;
	} else if (MCOperand_isImm(Op)) {
		// Print X86 immediates as signed values.
		int64_t imm = MCOperand_getImm(Op);
		SStream_concat(O, "%s$0x%"PRIx64"%s", markup("<imm:"), imm, markup(">"));
		MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].type = X86_OP_IMM;
		MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].imm = imm;
		MI->pub_insn.x86.op_count++;
	}
}

// local printOperand, without updating public operands
static void _printOperand(MCInst *MI, unsigned OpNo, SStream *O)
{
	MCOperand *Op  = MCInst_getOperand(MI, OpNo);
	if (MCOperand_isReg(Op)) {
		printRegName(O, MCOperand_getReg(Op));
	} else if (MCOperand_isImm(Op)) {
		// Print X86 immediates as signed values.
		int64_t imm = MCOperand_getImm(Op);
		if (imm < 0)
			SStream_concat(O, "%s$-0x%"PRIx64"%s", markup("<imm:"), -imm, markup(">"));
		else
			SStream_concat(O, "%s$0x%"PRIx64"%s", markup("<imm:"), imm, markup(">"));
	}
}

static void printMemReference(MCInst *MI, unsigned Op, SStream *O)
{
	MCOperand *BaseReg  = MCInst_getOperand(MI, Op);
	MCOperand *IndexReg  = MCInst_getOperand(MI, Op+2);
	MCOperand *DispSpec = MCInst_getOperand(MI, Op+3);
	MCOperand *SegReg = MCInst_getOperand(MI, Op+4);

	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].type = X86_OP_MEM;
	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.base = MCOperand_getReg(BaseReg);
	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.index = MCOperand_getReg(IndexReg);
	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.scale = 1;
	MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.disp = 0;

	SStream_concat(O, markup("<mem:"));

	// If this has a segment register, print it.
	if (MCOperand_getReg(SegReg)) {
		_printOperand(MI, Op+4, O);
		SStream_concat(O, ":");
	}

	if (MCOperand_isImm(DispSpec)) {
		int64_t DispVal = MCOperand_getImm(DispSpec);
		MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.disp = DispVal;
		if (DispVal || (!MCOperand_getReg(IndexReg) && !MCOperand_getReg(BaseReg))) {
			if (DispVal < 0)
				SStream_concat(O, "-0x%"PRIx64, -DispVal);
			else
				SStream_concat(O, "0x%"PRIx64, DispVal);
		}
	}

	if (MCOperand_getReg(IndexReg) || MCOperand_getReg(BaseReg)) {
		SStream_concat(O, "(");

		if (MCOperand_getReg(BaseReg))
			_printOperand(MI, Op, O);

		if (MCOperand_getReg(IndexReg)) {
			SStream_concat(O, ", ");
			_printOperand(MI, Op+2, O);
			unsigned ScaleVal = MCOperand_getImm(MCInst_getOperand(MI, Op+1));
			MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].mem.scale = ScaleVal;
			if (ScaleVal != 1) {
				SStream_concat(O, ", %s%u%s", markup("<imm:"), ScaleVal, markup(">"));
			}
		}
		SStream_concat(O, ")");
	}

	SStream_concat(O, markup(">"));

	MI->pub_insn.x86.op_count++;
}

#include "X86InstPrinter.h"

#define GET_INSTRINFO_ENUM
#include "X86GenInstrInfo.inc"

#define GET_REGINFO_ENUM
#include "X86GenRegisterInfo.inc"

// Include the auto-generated portion of the assembly writer.
#define PRINT_ALIAS_INSTR
#include "X86GenAsmWriter.inc"

static void printRegName(SStream *OS, unsigned RegNo)
{
	SStream_concat(OS, "%s%%%s%s", markup("<reg:"), getRegisterName(RegNo), markup(">"));
}

// get the first op from the asm buffer
// NOTE: make sure firstop is big enough to contain the resulted string
static void get_last_op(char *buffer, char *lastop)
{
	char *comma = strrchr(buffer, ',');
	if (comma) {
		// skip a space after the comma
		strcpy(lastop, comma + 2);
	} else	// no op
		lastop[0] = '\0';
}

void X86_ATT_printInst(MCInst *MI, SStream *OS, void *info)
{
	// FIXME
	//const MCInstrDesc *Desc = MII.get(MI->getOpcode());
	//uint64_t TSFlags = Desc.TSFlags;

	//if (TSFlags & X86II::LOCK)
	//  OS << "\tlock\n";

	// Try to print any aliases first.
	if (printAliasInstr(MI, OS)) {
		char *mnem = strdup(OS->buffer);
		char *tab = strchr(mnem, '\t');
		if (tab)
			*tab = '\0';
		// reflect the new insn name (alias) in the opcode
		MCInst_setOpcode(MI, X86_get_insn_id2(X86_map_insn(mnem)));
		free(mnem);
	} else
	   printInstruction(MI, OS);

	// first op can be embedded in the asm by llvm.
	// so we have to handle that case to not miss the first op.
	char lastop[32];
	get_last_op(OS->buffer, lastop);
	char *acc_regs[] = {"rax", "eax", "ax", "al", NULL};
	if (lastop[0] == '%' && str_in_list(acc_regs, lastop+1)) {
		// this is one of the registers AL, AX, EAX, RAX
		// canonicalize the register name first
		//int i;
		//for (i = 1; lastop[i]; i++)
		//	lastop[i] = tolower(lastop[i]);
		if (MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count - 1].type != X86_OP_REG) {
			MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].type = X86_OP_REG;
			MI->pub_insn.x86.operands[MI->pub_insn.x86.op_count].reg = x86_map_regname(lastop + 1);
			MI->pub_insn.x86.op_count++;
		}
	}
}