llvm-6502/lib/Target/X86/AsmPrinter/X86IntelInstPrinter.cpp
Chris Lattner 6aa928d57a I have manually decoded the imm field of an insertps one too many
times.  This patch causes llc and llvm-mc (which both default to
verbose-asm) to print out comments after a few common shuffle 
instructions which indicates the shuffle mask, e.g.:

	insertps	$113, %xmm3, %xmm0     ## xmm0 = zero,xmm0[1,2],xmm3[1]
	unpcklps	%xmm1, %xmm0    ## xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1]
	pshufd	$1, %xmm1, %xmm1        ## xmm1 = xmm1[1,0,0,0]

This is carefully factored to keep the information extraction (of the
shuffle mask) separate from the printing logic.  I plan to move the
extraction part out somewhere else at some point for other parts of
the x86 backend that want to introspect on the behavior of shuffles.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112387 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-28 20:42:31 +00:00

141 lines
4.0 KiB
C++

//===-- X86IntelInstPrinter.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.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "asm-printer"
#include "X86IntelInstPrinter.h"
#include "X86InstComments.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FormattedStream.h"
#include "X86GenInstrNames.inc"
using namespace llvm;
// Include the auto-generated portion of the assembly writer.
#define MachineInstr MCInst
#define GET_INSTRUCTION_NAME
#include "X86GenAsmWriter1.inc"
#undef MachineInstr
void X86IntelInstPrinter::printInst(const MCInst *MI, raw_ostream &OS) {
printInstruction(MI, OS);
// If verbose assembly is enabled, we can print some informative comments.
if (CommentStream)
EmitAnyX86InstComments(MI, *CommentStream, getRegisterName);
}
StringRef X86IntelInstPrinter::getOpcodeName(unsigned Opcode) const {
return getInstructionName(Opcode);
}
void X86IntelInstPrinter::printSSECC(const MCInst *MI, unsigned Op,
raw_ostream &O) {
switch (MI->getOperand(Op).getImm()) {
default: assert(0 && "Invalid ssecc argument!");
case 0: O << "eq"; break;
case 1: O << "lt"; break;
case 2: O << "le"; break;
case 3: O << "unord"; break;
case 4: O << "neq"; break;
case 5: O << "nlt"; break;
case 6: O << "nle"; break;
case 7: O << "ord"; break;
}
}
/// print_pcrel_imm - This is used to print an immediate value that ends up
/// being encoded as a pc-relative value.
void X86IntelInstPrinter::print_pcrel_imm(const MCInst *MI, unsigned OpNo,
raw_ostream &O) {
const MCOperand &Op = MI->getOperand(OpNo);
if (Op.isImm())
O << Op.getImm();
else {
assert(Op.isExpr() && "unknown pcrel immediate operand");
O << *Op.getExpr();
}
}
static void PrintRegName(raw_ostream &O, StringRef RegName) {
for (unsigned i = 0, e = RegName.size(); i != e; ++i)
O << (char)toupper(RegName[i]);
}
void X86IntelInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
raw_ostream &O) {
const MCOperand &Op = MI->getOperand(OpNo);
if (Op.isReg()) {
PrintRegName(O, getRegisterName(Op.getReg()));
} else if (Op.isImm()) {
O << Op.getImm();
} else {
assert(Op.isExpr() && "unknown operand kind in printOperand");
O << *Op.getExpr();
}
}
void X86IntelInstPrinter::printMemReference(const MCInst *MI, unsigned Op,
raw_ostream &O) {
const MCOperand &BaseReg = MI->getOperand(Op);
unsigned ScaleVal = MI->getOperand(Op+1).getImm();
const MCOperand &IndexReg = MI->getOperand(Op+2);
const MCOperand &DispSpec = MI->getOperand(Op+3);
const MCOperand &SegReg = MI->getOperand(Op+4);
// If this has a segment register, print it.
if (SegReg.getReg()) {
printOperand(MI, Op+4, O);
O << ':';
}
O << '[';
bool NeedPlus = false;
if (BaseReg.getReg()) {
printOperand(MI, Op, O);
NeedPlus = true;
}
if (IndexReg.getReg()) {
if (NeedPlus) O << " + ";
if (ScaleVal != 1)
O << ScaleVal << '*';
printOperand(MI, Op+2, O);
NeedPlus = true;
}
if (!DispSpec.isImm()) {
if (NeedPlus) O << " + ";
assert(DispSpec.isExpr() && "non-immediate displacement for LEA?");
O << *DispSpec.getExpr();
} else {
int64_t DispVal = DispSpec.getImm();
if (DispVal || (!IndexReg.getReg() && !BaseReg.getReg())) {
if (NeedPlus) {
if (DispVal > 0)
O << " + ";
else {
O << " - ";
DispVal = -DispVal;
}
}
O << DispVal;
}
}
O << ']';
}