llvm-6502/lib/Target/X86/X86MCAsmInfo.cpp
Rafael Espindola 89fc9e8f5e Enable CFI on OS X.
Currently the output should be almost identical to the one produced by CodeGen
to make the transition easier.

The only two differences I know of are:

* Some files get an extra advance loc of size 0. This will be fixed when
relaxations are enabled.
* The optimization of declaring an EH symbol as an external variable is not
implemented. This is a subset of adding the nounwind attribute, so we if really
this at -O0 we should probably do it at the IL level.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130623 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-30 22:29:54 +00:00

135 lines
4.0 KiB
C++

//===-- X86MCAsmInfo.cpp - X86 asm properties -----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the declarations of the X86MCAsmInfo properties.
//
//===----------------------------------------------------------------------===//
#include "X86MCAsmInfo.h"
#include "X86TargetMachine.h"
#include "llvm/ADT/Triple.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ELF.h"
using namespace llvm;
enum AsmWriterFlavorTy {
// Note: This numbering has to match the GCC assembler dialects for inline
// asm alternatives to work right.
ATT = 0, Intel = 1
};
static cl::opt<AsmWriterFlavorTy>
AsmWriterFlavor("x86-asm-syntax", cl::init(ATT),
cl::desc("Choose style of code to emit from X86 backend:"),
cl::values(clEnumValN(ATT, "att", "Emit AT&T-style assembly"),
clEnumValN(Intel, "intel", "Emit Intel-style assembly"),
clEnumValEnd));
static const char *const x86_asm_table[] = {
"{si}", "S",
"{di}", "D",
"{ax}", "a",
"{cx}", "c",
"{memory}", "memory",
"{flags}", "",
"{dirflag}", "",
"{fpsr}", "",
"{cc}", "cc",
0,0};
X86MCAsmInfoDarwin::X86MCAsmInfoDarwin(const Triple &Triple) {
AsmTransCBE = x86_asm_table;
AssemblerDialect = AsmWriterFlavor;
bool is64Bit = Triple.getArch() == Triple::x86_64;
TextAlignFillValue = 0x90;
if (!is64Bit)
Data64bitsDirective = 0; // we can't emit a 64-bit unit
// Use ## as a comment string so that .s files generated by llvm can go
// through the GCC preprocessor without causing an error. This is needed
// because "clang foo.s" runs the C preprocessor, which is usually reserved
// for .S files on other systems. Perhaps this is because the file system
// wasn't always case preserving or something.
CommentString = "##";
PCSymbol = ".";
SupportsDebugInformation = true;
DwarfUsesInlineInfoSection = true;
// Exceptions handling
ExceptionsType = ExceptionHandling::DwarfCFI;
}
const MCExpr *
X86_64MCAsmInfoDarwin::getExprForPersonalitySymbol(const MCSymbol *Sym,
MCStreamer &Streamer) const {
MCContext &Context = Streamer.getContext();
const MCExpr *Res =
MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_GOTPCREL, Context);
const MCExpr *Four = MCConstantExpr::Create(4, Context);
return MCBinaryExpr::CreateAdd(Res, Four, Context);
}
X86_64MCAsmInfoDarwin::X86_64MCAsmInfoDarwin(const Triple &Triple)
: X86MCAsmInfoDarwin(Triple) {
}
X86ELFMCAsmInfo::X86ELFMCAsmInfo(const Triple &T) {
AsmTransCBE = x86_asm_table;
AssemblerDialect = AsmWriterFlavor;
TextAlignFillValue = 0x90;
PrivateGlobalPrefix = ".L";
WeakRefDirective = "\t.weak\t";
PCSymbol = ".";
// Set up DWARF directives
HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
// Debug Information
SupportsDebugInformation = true;
// Exceptions handling
ExceptionsType = ExceptionHandling::DwarfCFI;
DwarfRequiresFrameSection = false;
// OpenBSD has buggy support for .quad in 32-bit mode, just split into two
// .words.
if (T.getOS() == Triple::OpenBSD && T.getArch() == Triple::x86)
Data64bitsDirective = 0;
}
const MCSection *X86ELFMCAsmInfo::
getNonexecutableStackSection(MCContext &Ctx) const {
return Ctx.getELFSection(".note.GNU-stack", ELF::SHT_PROGBITS,
0, SectionKind::getMetadata());
}
X86MCAsmInfoCOFF::X86MCAsmInfoCOFF(const Triple &Triple) {
if (Triple.getArch() == Triple::x86_64) {
GlobalPrefix = "";
PrivateGlobalPrefix = ".L";
}
AsmTransCBE = x86_asm_table;
AssemblerDialect = AsmWriterFlavor;
TextAlignFillValue = 0x90;
}