llvm-6502/lib/CodeGen/LLVMTargetMachine.cpp
Rafael Espindola 195a0ce484 Change some methods in MCDwarf.cpp to be able to handle an arbitrary
MCStreamer instead of just MCObjectStreamer. Address changes cannot
be as efficient as we have to use DW_LNE_set_addres, but at least
most of the logic is shared.

This will be used so that, with CodeGen still using EmitDwarfLocDirective,
llvm-gcc is able to produce debug_line sections without needing an
assembler that supports .loc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119777 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-19 02:26:16 +00:00

473 lines
17 KiB
C++

//===-- LLVMTargetMachine.cpp - Implement the LLVMTargetMachine class -----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the LLVMTargetMachine class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Target/TargetMachine.h"
#include "llvm/PassManager.h"
#include "llvm/Analysis/Verifier.h"
#include "llvm/Assembly/PrintModulePass.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineFunctionAnalysis.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/GCStrategy.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/StandardPasses.h"
using namespace llvm;
namespace llvm {
bool EnableFastISel;
}
static cl::opt<bool> DisablePostRA("disable-post-ra", cl::Hidden,
cl::desc("Disable Post Regalloc"));
static cl::opt<bool> DisableBranchFold("disable-branch-fold", cl::Hidden,
cl::desc("Disable branch folding"));
static cl::opt<bool> DisableTailDuplicate("disable-tail-duplicate", cl::Hidden,
cl::desc("Disable tail duplication"));
static cl::opt<bool> DisableEarlyTailDup("disable-early-taildup", cl::Hidden,
cl::desc("Disable pre-register allocation tail duplication"));
static cl::opt<bool> DisableCodePlace("disable-code-place", cl::Hidden,
cl::desc("Disable code placement"));
static cl::opt<bool> DisableSSC("disable-ssc", cl::Hidden,
cl::desc("Disable Stack Slot Coloring"));
static cl::opt<bool> DisableMachineLICM("disable-machine-licm", cl::Hidden,
cl::desc("Disable Machine LICM"));
static cl::opt<bool> DisablePostRAMachineLICM("disable-postra-machine-licm",
cl::Hidden,
cl::desc("Disable Machine LICM"));
static cl::opt<bool> DisableMachineSink("disable-machine-sink", cl::Hidden,
cl::desc("Disable Machine Sinking"));
static cl::opt<bool> DisableLSR("disable-lsr", cl::Hidden,
cl::desc("Disable Loop Strength Reduction Pass"));
static cl::opt<bool> DisableCGP("disable-cgp", cl::Hidden,
cl::desc("Disable Codegen Prepare"));
static cl::opt<bool> PrintLSR("print-lsr-output", cl::Hidden,
cl::desc("Print LLVM IR produced by the loop-reduce pass"));
static cl::opt<bool> PrintISelInput("print-isel-input", cl::Hidden,
cl::desc("Print LLVM IR input to isel pass"));
static cl::opt<bool> PrintGCInfo("print-gc", cl::Hidden,
cl::desc("Dump garbage collector data"));
static cl::opt<bool> ShowMCEncoding("show-mc-encoding", cl::Hidden,
cl::desc("Show encoding in .s output"));
static cl::opt<bool> ShowMCInst("show-mc-inst", cl::Hidden,
cl::desc("Show instruction structure in .s output"));
static cl::opt<bool> EnableMCLogging("enable-mc-api-logging", cl::Hidden,
cl::desc("Enable MC API logging"));
static cl::opt<bool> VerifyMachineCode("verify-machineinstrs", cl::Hidden,
cl::desc("Verify generated machine code"),
cl::init(getenv("LLVM_VERIFY_MACHINEINSTRS")!=NULL));
static cl::opt<cl::boolOrDefault>
AsmVerbose("asm-verbose", cl::desc("Add comments to directives."),
cl::init(cl::BOU_UNSET));
static bool getVerboseAsm() {
switch (AsmVerbose) {
default:
case cl::BOU_UNSET: return TargetMachine::getAsmVerbosityDefault();
case cl::BOU_TRUE: return true;
case cl::BOU_FALSE: return false;
}
}
// Enable or disable FastISel. Both options are needed, because
// FastISel is enabled by default with -fast, and we wish to be
// able to enable or disable fast-isel independently from -O0.
static cl::opt<cl::boolOrDefault>
EnableFastISelOption("fast-isel", cl::Hidden,
cl::desc("Enable the \"fast\" instruction selector"));
// Enable or disable an experimental optimization to split GEPs
// and run a special GVN pass which does not examine loads, in
// an effort to factor out redundancy implicit in complex GEPs.
static cl::opt<bool> EnableSplitGEPGVN("split-gep-gvn", cl::Hidden,
cl::desc("Split GEPs and run no-load GVN"));
LLVMTargetMachine::LLVMTargetMachine(const Target &T,
const std::string &Triple)
: TargetMachine(T), TargetTriple(Triple) {
AsmInfo = T.createAsmInfo(TargetTriple);
}
// Set the default code model for the JIT for a generic target.
// FIXME: Is small right here? or .is64Bit() ? Large : Small?
void LLVMTargetMachine::setCodeModelForJIT() {
setCodeModel(CodeModel::Small);
}
// Set the default code model for static compilation for a generic target.
void LLVMTargetMachine::setCodeModelForStatic() {
setCodeModel(CodeModel::Small);
}
bool LLVMTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
formatted_raw_ostream &Out,
CodeGenFileType FileType,
CodeGenOpt::Level OptLevel,
bool DisableVerify) {
// Add common CodeGen passes.
MCContext *Context = 0;
if (addCommonCodeGenPasses(PM, OptLevel, DisableVerify, Context))
return true;
assert(Context != 0 && "Failed to get MCContext");
const MCAsmInfo &MAI = *getMCAsmInfo();
OwningPtr<MCStreamer> AsmStreamer;
switch (FileType) {
default: return true;
case CGFT_AssemblyFile: {
MCInstPrinter *InstPrinter =
getTarget().createMCInstPrinter(MAI.getAssemblerDialect(), MAI);
// Create a code emitter if asked to show the encoding.
MCCodeEmitter *MCE = 0;
if (ShowMCEncoding)
MCE = getTarget().createCodeEmitter(*this, *Context);
const TargetLoweringObjectFile &TLOF =
getTargetLowering()->getObjFileLowering();
int PointerSize = getTargetData()->getPointerSize();
MCStreamer *S;
if (hasMCUseLoc())
S = getTarget().createAsmStreamer(*Context, Out,
getTargetData()->isLittleEndian(),
getVerboseAsm(),
InstPrinter,
MCE,
ShowMCInst);
else
S = createAsmStreamerNoLoc(*Context, Out,
getTargetData()->isLittleEndian(),
getVerboseAsm(),
&TLOF,
PointerSize,
InstPrinter,
MCE,
ShowMCInst);
AsmStreamer.reset(S);
break;
}
case CGFT_ObjectFile: {
// Create the code emitter for the target if it exists. If not, .o file
// emission fails.
MCCodeEmitter *MCE = getTarget().createCodeEmitter(*this, *Context);
TargetAsmBackend *TAB = getTarget().createAsmBackend(TargetTriple);
if (MCE == 0 || TAB == 0)
return true;
AsmStreamer.reset(getTarget().createObjectStreamer(TargetTriple, *Context,
*TAB, Out, MCE,
hasMCRelaxAll()));
AsmStreamer.get()->InitSections();
break;
}
case CGFT_Null:
// The Null output is intended for use for performance analysis and testing,
// not real users.
AsmStreamer.reset(createNullStreamer(*Context));
break;
}
if (EnableMCLogging)
AsmStreamer.reset(createLoggingStreamer(AsmStreamer.take(), errs()));
// Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
FunctionPass *Printer = getTarget().createAsmPrinter(*this, *AsmStreamer);
if (Printer == 0)
return true;
// If successful, createAsmPrinter took ownership of AsmStreamer.
AsmStreamer.take();
PM.add(Printer);
// Make sure the code model is set.
setCodeModelForStatic();
PM.add(createGCInfoDeleter());
return false;
}
/// addPassesToEmitMachineCode - Add passes to the specified pass manager to
/// get machine code emitted. This uses a JITCodeEmitter object to handle
/// actually outputting the machine code and resolving things like the address
/// of functions. This method should returns true if machine code emission is
/// not supported.
///
bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM,
JITCodeEmitter &JCE,
CodeGenOpt::Level OptLevel,
bool DisableVerify) {
// Make sure the code model is set.
setCodeModelForJIT();
// Add common CodeGen passes.
MCContext *Ctx = 0;
if (addCommonCodeGenPasses(PM, OptLevel, DisableVerify, Ctx))
return true;
addCodeEmitter(PM, OptLevel, JCE);
PM.add(createGCInfoDeleter());
return false; // success!
}
/// addPassesToEmitMC - Add passes to the specified pass manager to get
/// machine code emitted with the MCJIT. This method returns true if machine
/// code is not supported. It fills the MCContext Ctx pointer which can be
/// used to build custom MCStreamer.
///
bool LLVMTargetMachine::addPassesToEmitMC(PassManagerBase &PM,
MCContext *&Ctx,
CodeGenOpt::Level OptLevel,
bool DisableVerify) {
// Add common CodeGen passes.
if (addCommonCodeGenPasses(PM, OptLevel, DisableVerify, Ctx))
return true;
// Make sure the code model is set.
setCodeModelForJIT();
return false; // success!
}
static void printNoVerify(PassManagerBase &PM, const char *Banner) {
if (PrintMachineCode)
PM.add(createMachineFunctionPrinterPass(dbgs(), Banner));
}
static void printAndVerify(PassManagerBase &PM,
const char *Banner) {
if (PrintMachineCode)
PM.add(createMachineFunctionPrinterPass(dbgs(), Banner));
if (VerifyMachineCode)
PM.add(createMachineVerifierPass());
}
/// addCommonCodeGenPasses - Add standard LLVM codegen passes used for both
/// emitting to assembly files or machine code output.
///
bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
CodeGenOpt::Level OptLevel,
bool DisableVerify,
MCContext *&OutContext) {
// Standard LLVM-Level Passes.
// Basic AliasAnalysis support.
createStandardAliasAnalysisPasses(&PM);
// Before running any passes, run the verifier to determine if the input
// coming from the front-end and/or optimizer is valid.
if (!DisableVerify)
PM.add(createVerifierPass());
// Optionally, tun split-GEPs and no-load GVN.
if (EnableSplitGEPGVN) {
PM.add(createGEPSplitterPass());
PM.add(createGVNPass(/*NoLoads=*/true));
}
// Run loop strength reduction before anything else.
if (OptLevel != CodeGenOpt::None && !DisableLSR) {
PM.add(createLoopStrengthReducePass(getTargetLowering()));
if (PrintLSR)
PM.add(createPrintFunctionPass("\n\n*** Code after LSR ***\n", &dbgs()));
}
PM.add(createGCLoweringPass());
// Make sure that no unreachable blocks are instruction selected.
PM.add(createUnreachableBlockEliminationPass());
// Turn exception handling constructs into something the code generators can
// handle.
switch (getMCAsmInfo()->getExceptionHandlingType()) {
case ExceptionHandling::SjLj:
// SjLj piggy-backs on dwarf for this bit. The cleanups done apply to both
// Dwarf EH prepare needs to be run after SjLj prepare. Otherwise,
// catch info can get misplaced when a selector ends up more than one block
// removed from the parent invoke(s). This could happen when a landing
// pad is shared by multiple invokes and is also a target of a normal
// edge from elsewhere.
PM.add(createSjLjEHPass(getTargetLowering()));
// FALLTHROUGH
case ExceptionHandling::Dwarf:
PM.add(createDwarfEHPass(this));
break;
case ExceptionHandling::None:
PM.add(createLowerInvokePass(getTargetLowering()));
// The lower invoke pass may create unreachable code. Remove it.
PM.add(createUnreachableBlockEliminationPass());
break;
}
if (OptLevel != CodeGenOpt::None && !DisableCGP)
PM.add(createCodeGenPreparePass(getTargetLowering()));
PM.add(createStackProtectorPass(getTargetLowering()));
addPreISel(PM, OptLevel);
if (PrintISelInput)
PM.add(createPrintFunctionPass("\n\n"
"*** Final LLVM Code input to ISel ***\n",
&dbgs()));
// All passes which modify the LLVM IR are now complete; run the verifier
// to ensure that the IR is valid.
if (!DisableVerify)
PM.add(createVerifierPass());
// Standard Lower-Level Passes.
// Install a MachineModuleInfo class, which is an immutable pass that holds
// all the per-module stuff we're generating, including MCContext.
MachineModuleInfo *MMI = new MachineModuleInfo(*getMCAsmInfo());
PM.add(MMI);
OutContext = &MMI->getContext(); // Return the MCContext specifically by-ref.
// Set up a MachineFunction for the rest of CodeGen to work on.
PM.add(new MachineFunctionAnalysis(*this, OptLevel));
// Enable FastISel with -fast, but allow that to be overridden.
if (EnableFastISelOption == cl::BOU_TRUE ||
(OptLevel == CodeGenOpt::None && EnableFastISelOption != cl::BOU_FALSE))
EnableFastISel = true;
// Ask the target for an isel.
if (addInstSelector(PM, OptLevel))
return true;
// Print the instruction selected machine code...
printAndVerify(PM, "After Instruction Selection");
// Expand pseudo-instructions emitted by ISel.
PM.add(createExpandISelPseudosPass());
// Optimize PHIs before DCE: removing dead PHI cycles may make more
// instructions dead.
if (OptLevel != CodeGenOpt::None)
PM.add(createOptimizePHIsPass());
// If the target requests it, assign local variables to stack slots relative
// to one another and simplify frame index references where possible.
PM.add(createLocalStackSlotAllocationPass());
if (OptLevel != CodeGenOpt::None) {
// With optimization, dead code should already be eliminated. However
// there is one known exception: lowered code for arguments that are only
// used by tail calls, where the tail calls reuse the incoming stack
// arguments directly (see t11 in test/CodeGen/X86/sibcall.ll).
PM.add(createDeadMachineInstructionElimPass());
printAndVerify(PM, "After codegen DCE pass");
if (!DisableMachineLICM)
PM.add(createMachineLICMPass());
PM.add(createMachineCSEPass());
if (!DisableMachineSink)
PM.add(createMachineSinkingPass());
printAndVerify(PM, "After Machine LICM, CSE and Sinking passes");
PM.add(createPeepholeOptimizerPass());
printAndVerify(PM, "After codegen peephole optimization pass");
}
// Pre-ra tail duplication.
if (OptLevel != CodeGenOpt::None && !DisableEarlyTailDup) {
PM.add(createTailDuplicatePass(true));
printAndVerify(PM, "After Pre-RegAlloc TailDuplicate");
}
// Run pre-ra passes.
if (addPreRegAlloc(PM, OptLevel))
printAndVerify(PM, "After PreRegAlloc passes");
// Perform register allocation.
PM.add(createRegisterAllocator(OptLevel));
printAndVerify(PM, "After Register Allocation");
// Perform stack slot coloring and post-ra machine LICM.
if (OptLevel != CodeGenOpt::None) {
// FIXME: Re-enable coloring with register when it's capable of adding
// kill markers.
if (!DisableSSC)
PM.add(createStackSlotColoringPass(false));
// Run post-ra machine LICM to hoist reloads / remats.
if (!DisablePostRAMachineLICM)
PM.add(createMachineLICMPass(false));
printAndVerify(PM, "After StackSlotColoring and postra Machine LICM");
}
// Run post-ra passes.
if (addPostRegAlloc(PM, OptLevel))
printAndVerify(PM, "After PostRegAlloc passes");
PM.add(createLowerSubregsPass());
printAndVerify(PM, "After LowerSubregs");
// Insert prolog/epilog code. Eliminate abstract frame index references...
PM.add(createPrologEpilogCodeInserter());
printAndVerify(PM, "After PrologEpilogCodeInserter");
// Run pre-sched2 passes.
if (addPreSched2(PM, OptLevel))
printAndVerify(PM, "After PreSched2 passes");
// Second pass scheduler.
if (OptLevel != CodeGenOpt::None && !DisablePostRA) {
PM.add(createPostRAScheduler(OptLevel));
printAndVerify(PM, "After PostRAScheduler");
}
// Branch folding must be run after regalloc and prolog/epilog insertion.
if (OptLevel != CodeGenOpt::None && !DisableBranchFold) {
PM.add(createBranchFoldingPass(getEnableTailMergeDefault()));
printNoVerify(PM, "After BranchFolding");
}
// Tail duplication.
if (OptLevel != CodeGenOpt::None && !DisableTailDuplicate) {
PM.add(createTailDuplicatePass(false));
printNoVerify(PM, "After TailDuplicate");
}
PM.add(createGCMachineCodeAnalysisPass());
if (PrintGCInfo)
PM.add(createGCInfoPrinter(dbgs()));
if (OptLevel != CodeGenOpt::None && !DisableCodePlace) {
PM.add(createCodePlacementOptPass());
printNoVerify(PM, "After CodePlacementOpt");
}
if (addPreEmitPass(PM, OptLevel))
printNoVerify(PM, "After PreEmit passes");
return false;
}