llvm-6502/lib/MC/MCAsmInfo.cpp

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//===-- MCAsmInfo.cpp - Asm Info -------------------------------------------==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines target asm properties related what form asm statements
// should take.
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/Dwarf.h"
#include <cctype>
#include <cstring>
using namespace llvm;
MCAsmInfo::MCAsmInfo() {
PointerSize = 4;
CalleeSaveStackSlotSize = 4;
IsLittleEndian = true;
StackGrowsUp = false;
HasSubsectionsViaSymbols = false;
HasMachoZeroFillDirective = false;
HasMachoTBSSDirective = false;
HasStaticCtorDtorReferenceInStaticMode = false;
LinkerRequiresNonEmptyDwarfLines = false;
MaxInstLength = 4;
MinInstAlignment = 1;
DollarIsPC = false;
SeparatorString = ";";
CommentString = "#";
LabelSuffix = ":";
This patch is needed to make c++ exceptions work for mips16. Mips16 is really a processor decoding mode (ala thumb 1) and in the same program, mips16 and mips32 functions can exist and can call each other. If a jal type instruction encounters an address with the lower bit set, then the processor switches to mips16 mode (if it is not already in it). If the lower bit is not set, then it switches to mips32 mode. The linker knows which functions are mips16 and which are mips32. When relocation is performed on code labels, this lower order bit is set if the code label is a mips16 code label. In general this works just fine, however when creating exception handling tables and dwarf, there are cases where you don't want this lower order bit added in. This has been traditionally distinguished in gas assembly source by using a different syntax for the label. lab1: ; this will cause the lower order bit to be added lab2=. ; this will not cause the lower order bit to be added In some cases, it does not matter because in dwarf and debug tables the difference of two labels is used and in that case the lower order bits subtract each other out. To fix this, I have added to mcstreamer the notion of a debuglabel. The default is for label and debug label to be the same. So calling EmitLabel and EmitDebugLabel produce the same result. For various reasons, there is only one set of labels that needs to be modified for the mips exceptions to work. These are the "$eh_func_beginXXX" labels. Mips overrides the debug label suffix from ":" to "=." . This initial patch fixes exceptions. More changes most likely will be needed to DwarfCFException to make all of this work for actual debugging. These changes will be to emit debug labels in some places where a simple label is emitted now. Some historical discussion on this from gcc can be found at: http://gcc.gnu.org/ml/gcc-patches/2008-08/msg00623.html http://gcc.gnu.org/ml/gcc-patches/2008-11/msg01273.html git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170279 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-16 04:00:45 +00:00
DebugLabelSuffix = ":";
PrivateGlobalPrefix = "L";
LinkerPrivateGlobalPrefix = "";
InlineAsmStart = "APP";
InlineAsmEnd = "NO_APP";
Code16Directive = ".code16";
Code32Directive = ".code32";
Code64Directive = ".code64";
AssemblerDialect = 0;
AllowAtInName = false;
UseDataRegionDirectives = false;
ZeroDirective = "\t.zero\t";
AsciiDirective = "\t.ascii\t";
AscizDirective = "\t.asciz\t";
Data8bitsDirective = "\t.byte\t";
Data16bitsDirective = "\t.short\t";
Data32bitsDirective = "\t.long\t";
Data64bitsDirective = "\t.quad\t";
SunStyleELFSectionSwitchSyntax = false;
UsesELFSectionDirectiveForBSS = false;
AlignmentIsInBytes = true;
TextAlignFillValue = 0;
GPRel64Directive = nullptr;
GPRel32Directive = nullptr;
GlobalDirective = "\t.globl\t";
HasSetDirective = true;
HasAggressiveSymbolFolding = true;
COMMDirectiveAlignmentIsInBytes = true;
LCOMMDirectiveAlignmentType = LCOMM::NoAlignment;
HasDotTypeDotSizeDirective = true;
HasSingleParameterDotFile = true;
HasIdentDirective = false;
HasNoDeadStrip = false;
WeakRefDirective = nullptr;
HasWeakDefDirective = false;
HasWeakDefCanBeHiddenDirective = false;
HasLinkOnceDirective = false;
HiddenVisibilityAttr = MCSA_Hidden;
HiddenDeclarationVisibilityAttr = MCSA_Hidden;
ProtectedVisibilityAttr = MCSA_Protected;
HasLEB128 = false;
SupportsDebugInformation = false;
ExceptionsType = ExceptionHandling::None;
DwarfUsesRelocationsAcrossSections = true;
DwarfFDESymbolsUseAbsDiff = false;
DwarfRegNumForCFI = false;
NeedsDwarfSectionOffsetDirective = false;
UseParensForSymbolVariant = false;
Re-commit: Demote EmitRawText call in AsmPrinter::EmitInlineAsm() and remove hasRawTextSupport() call Summary: AsmPrinter::EmitInlineAsm() will no longer use the EmitRawText() call for targets with mature MC support. Such targets will always parse the inline assembly (even when emitting assembly). Targets without mature MC support continue to use EmitRawText() for assembly output. The hasRawTextSupport() check in AsmPrinter::EmitInlineAsm() has been replaced with MCAsmInfo::UseIntegratedAs which when true, causes the integrated assembler to parse inline assembly (even when emitting assembly output). UseIntegratedAs is set to true for targets that consider any failure to parse valid assembly to be a bug. Target specific subclasses generally enable the integrated assembler in their constructor. The default value can be overridden with -no-integrated-as. All tests that rely on inline assembly supporting invalid assembly (for example, those that use mnemonics such as 'foo' or 'hello world') have been updated to disable the integrated assembler. Changes since review (and last commit attempt): - Fixed test failures that were missed due to configuration of local build. (fixes crash.ll and a couple others). - Fixed tests that happened to pass because the local build was on X86 (should fix 2007-12-17-InvokeAsm.ll) - mature-mc-support.ll's should no longer require all targets to be compiled. (should fix ARM and PPC buildbots) - Object output (-filetype=obj and similar) now forces the integrated assembler to be enabled regardless of default setting or -no-integrated-as. (should fix SystemZ buildbots) Reviewers: rafael Reviewed By: rafael CC: llvm-commits Differential Revision: http://llvm-reviews.chandlerc.com/D2686 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201333 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-13 14:44:26 +00:00
// FIXME: Clang's logic should be synced with the logic used to initialize
// this member and the two implementations should be merged.
// For reference:
// - Solaris always enables the integrated assembler by default
// - SparcELFMCAsmInfo and X86ELFMCAsmInfo are handling this case
// - Windows always enables the integrated assembler by default
// - MCAsmInfoCOFF is handling this case, should it be MCAsmInfoMicrosoft?
// - MachO targets always enables the integrated assembler by default
// - MCAsmInfoDarwin is handling this case
// - Generic_GCC toolchains enable the integrated assembler on a per
// architecture basis.
// - The target subclasses for AArch64, ARM, and X86 handle these cases
UseIntegratedAssembler = false;
CompressDebugSections = false;
}
MCAsmInfo::~MCAsmInfo() {
}
const MCExpr *
MCAsmInfo::getExprForPersonalitySymbol(const MCSymbol *Sym,
unsigned Encoding,
MCStreamer &Streamer) const {
return getExprForFDESymbol(Sym, Encoding, Streamer);
}
const MCExpr *
MCAsmInfo::getExprForFDESymbol(const MCSymbol *Sym,
unsigned Encoding,
MCStreamer &Streamer) const {
if (!(Encoding & dwarf::DW_EH_PE_pcrel))
return MCSymbolRefExpr::Create(Sym, Streamer.getContext());
MCContext &Context = Streamer.getContext();
const MCExpr *Res = MCSymbolRefExpr::Create(Sym, Context);
MCSymbol *PCSym = Context.CreateTempSymbol();
Streamer.EmitLabel(PCSym);
const MCExpr *PC = MCSymbolRefExpr::Create(PCSym, Context);
return MCBinaryExpr::CreateSub(Res, PC, Context);
}