llvm/lib/CodeGen/LLVMTargetMachine.cpp
Chris Lattner 3813d8adf3 Remove a bunch of stuff around the edges of the ELF writer.
Now the only use of the ELF writer is the JIT, which won't be
easy to fix in the short term. :( :(



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95148 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 22:31:11 +00:00

316 lines
11 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/Pass.h"
#include "llvm/Assembly/PrintModulePass.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/GCStrategy.h"
#include "llvm/CodeGen/MachineFunctionAnalysis.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FormattedStream.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> 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> VerifyMachineCode("verify-machineinstrs", cl::Hidden,
cl::desc("Verify generated machine code"),
cl::init(getenv("LLVM_VERIFY_MACHINEINSTRS")!=NULL));
// 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 &TargetTriple)
: TargetMachine(T) {
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);
}
TargetMachine::CodeGenFileType
LLVMTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
formatted_raw_ostream &Out,
CodeGenFileType FileType,
CodeGenOpt::Level OptLevel) {
// Add common CodeGen passes.
if (addCommonCodeGenPasses(PM, OptLevel))
return CGFT_ErrorOccurred;
switch (FileType) {
default:
case CGFT_ObjectFile:
return CGFT_ErrorOccurred;
case CGFT_AssemblyFile: {
FunctionPass *Printer =
getTarget().createAsmPrinter(Out, *this, getMCAsmInfo(),
getAsmVerbosityDefault());
if (Printer == 0) return CGFT_ErrorOccurred;
PM.add(Printer);
break;
}
}
// Make sure the code model is set.
setCodeModelForStatic();
PM.add(createGCInfoDeleter());
return FileType;
}
/// 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) {
// Make sure the code model is set.
setCodeModelForJIT();
// Add common CodeGen passes.
if (addCommonCodeGenPasses(PM, OptLevel))
return true;
addCodeEmitter(PM, OptLevel, JCE);
PM.add(createGCInfoDeleter());
return false; // success!
}
static void printAndVerify(PassManagerBase &PM,
const char *Banner,
bool allowDoubleDefs = false) {
if (PrintMachineCode)
PM.add(createMachineFunctionPrinterPass(dbgs(), Banner));
if (VerifyMachineCode)
PM.add(createMachineVerifierPass(allowDoubleDefs));
}
/// 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) {
// Standard LLVM-Level Passes.
// Optionally, tun split-GEPs and no-load GVN.
if (EnableSplitGEPGVN) {
PM.add(createGEPSplitterPass());
PM.add(createGVNPass(/*NoPRE=*/false, /*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()));
}
// 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()));
PM.add(createDwarfEHPass(getTargetLowering(), OptLevel==CodeGenOpt::None));
break;
case ExceptionHandling::Dwarf:
PM.add(createDwarfEHPass(getTargetLowering(), OptLevel==CodeGenOpt::None));
break;
case ExceptionHandling::None:
PM.add(createLowerInvokePass(getTargetLowering()));
break;
}
PM.add(createGCLoweringPass());
// Make sure that no unreachable blocks are instruction selected.
PM.add(createUnreachableBlockEliminationPass());
if (OptLevel != CodeGenOpt::None && !DisableCGP)
PM.add(createCodeGenPreparePass(getTargetLowering()));
PM.add(createStackProtectorPass(getTargetLowering()));
if (PrintISelInput)
PM.add(createPrintFunctionPass("\n\n"
"*** Final LLVM Code input to ISel ***\n",
&dbgs()));
// Standard Lower-Level Passes.
// 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",
/* allowDoubleDefs= */ true);
if (OptLevel != CodeGenOpt::None) {
PM.add(createOptimizeExtsPass());
if (!DisableMachineLICM)
PM.add(createMachineLICMPass());
if (!DisableMachineSink)
PM.add(createMachineSinkingPass());
printAndVerify(PM, "After MachineLICM and MachineSinking",
/* allowDoubleDefs= */ true);
}
// Pre-ra tail duplication.
if (OptLevel != CodeGenOpt::None && !DisableEarlyTailDup) {
PM.add(createTailDuplicatePass(true));
printAndVerify(PM, "After Pre-RegAlloc TailDuplicate",
/* allowDoubleDefs= */ true);
}
// Run pre-ra passes.
if (addPreRegAlloc(PM, OptLevel))
printAndVerify(PM, "After PreRegAlloc passes",
/* allowDoubleDefs= */ true);
// Perform register allocation.
PM.add(createRegisterAllocator());
printAndVerify(PM, "After Register Allocation");
// Perform stack slot coloring.
if (OptLevel != CodeGenOpt::None && !DisableSSC) {
// FIXME: Re-enable coloring with register when it's capable of adding
// kill markers.
PM.add(createStackSlotColoringPass(false));
printAndVerify(PM, "After StackSlotColoring");
}
// 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()));
printAndVerify(PM, "After BranchFolding");
}
// Tail duplication.
if (OptLevel != CodeGenOpt::None && !DisableTailDuplicate) {
PM.add(createTailDuplicatePass(false));
printAndVerify(PM, "After TailDuplicate");
}
PM.add(createGCMachineCodeAnalysisPass());
if (PrintGCInfo)
PM.add(createGCInfoPrinter(dbgs()));
if (OptLevel != CodeGenOpt::None && !DisableCodePlace) {
PM.add(createCodePlacementOptPass());
printAndVerify(PM, "After CodePlacementOpt");
}
if (addPreEmitPass(PM, OptLevel))
printAndVerify(PM, "After PreEmit passes");
return false;
}