+//===-- gccas.cpp - The "optimizing assembler" used by the GCC frontend ---===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
//===----------------------------------------------------------------------===//
-// LLVM 'GCCAS' UTILITY
//
-// This utility is designed to be used by the GCC frontend for creating
-// bytecode files from it's intermediate llvm assembly. The requirements for
-// this utility are thus slightly different than that of the standard as util.
+// This utility is designed to be used by the GCC frontend for creating bytecode
+// files from its intermediate LLVM assembly. The requirements for this utility
+// are thus slightly different than that of the standard `as' util.
//
//===----------------------------------------------------------------------===//
#include "llvm/Module.h"
#include "llvm/PassManager.h"
-#include "llvm/Assembly/Parser.h"
-#include "llvm/Transforms/RaisePointerReferences.h"
-#include "llvm/Transforms/IPO.h"
-#include "llvm/Transforms/Scalar.h"
+#include "llvm/Analysis/LoadValueNumbering.h"
#include "llvm/Analysis/Verifier.h"
+#include "llvm/Assembly/Parser.h"
#include "llvm/Bytecode/WriteBytecodePass.h"
#include "llvm/Target/TargetData.h"
-#include "Support/CommandLine.h"
-#include "Support/Signals.h"
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Transforms/Scalar.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/System/Signals.h"
#include <memory>
#include <fstream>
-using std::cerr;
-// FIXME: This should eventually be parameterized...
-static TargetData TD("opt target");
+using namespace llvm;
-static cl::opt<std::string>
-InputFilename(cl::Positional, cl::desc("<input llvm assembly>"), cl::Required);
+namespace {
+ cl::opt<std::string>
+ InputFilename(cl::Positional,cl::desc("<input llvm assembly>"),cl::init("-"));
-static cl::opt<std::string>
-OutputFilename("o", cl::desc("Override output filename"),
- cl::value_desc("filename"));
+ cl::opt<std::string>
+ OutputFilename("o", cl::desc("Override output filename"),
+ cl::value_desc("filename"));
-static cl::opt<int>
-RunNPasses("stopAfterNPasses",
- cl::desc("Only run the first N passes of gccas"), cl::Hidden,
- cl::value_desc("# passes"));
+ cl::opt<bool>
+ Verify("verify", cl::desc("Verify each pass result"));
-static cl::opt<bool>
-StopAtLevelRaise("stopraise", cl::desc("Stop optimization before level raise"),
- cl::Hidden);
+ cl::opt<bool>
+ DisableInline("disable-inlining", cl::desc("Do not run the inliner pass"));
-static cl::opt<bool>
-Verify("verify", cl::desc("Verify each pass result"));
+ cl::opt<bool>
+ DisableOptimizations("disable-opt",
+ cl::desc("Do not run any optimization passes"));
+
+ cl::opt<bool>
+ DisableDSE("disable-dse", cl::desc("Do not run dead store elimination"));
+ cl::opt<bool>
+ NoCompress("disable-compression", cl::init(false),
+ cl::desc("Don't ompress the generated bytecode"));
+}
static inline void addPass(PassManager &PM, Pass *P) {
- static int NumPassesCreated = 0;
+ // Add the pass to the pass manager...
+ PM.add(P);
- // If we haven't already created the number of passes that was requested...
- if (RunNPasses == 0 || RunNPasses > NumPassesCreated) {
- // Add the pass to the pass manager...
- PM.add(P);
-
- // If we are verifying all of the intermediate steps, add the verifier...
- if (Verify) PM.add(createVerifierPass());
-
- // Keep track of how many passes we made for -stopAfterNPasses
- ++NumPassesCreated;
- }
+ // If we are verifying all of the intermediate steps, add the verifier...
+ if (Verify) PM.add(createVerifierPass());
}
void AddConfiguredTransformationPasses(PassManager &PM) {
- if (Verify) PM.add(createVerifierPass());
-
- addPass(PM, createFunctionResolvingPass()); // Resolve (...) functions
- addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
- addPass(PM, createConstantMergePass()); // Merge dup global constants
- addPass(PM, createDeadInstEliminationPass()); // Remove Dead code/vars
- addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
- addPass(PM, createIndVarSimplifyPass()); // Simplify indvars
-
- // Level raise is eternally buggy/in need of enhancements. Allow
- // transformation to stop right before it runs.
- if (StopAtLevelRaise) return;
-
- addPass(PM, createRaisePointerReferencesPass(TD));// Eliminate casts
- addPass(PM, createPromoteMemoryToRegister()); // Promote alloca's to regs
- // Disabling until this is fixed -- Vikram, 7/7/02.
- // addPass(PM, createReassociatePass()); // Reassociate expressions
- addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
- addPass(PM, createDeadInstEliminationPass()); // Kill InstCombine remnants
- addPass(PM, createLICMPass()); // Hoist loop invariants
- addPass(PM, createGCSEPass()); // Remove common subexprs
- addPass(PM, createSCCPPass()); // Constant prop with SCCP
+ PM.add(createVerifierPass()); // Verify that input is correct
+ addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp
+ addPass(PM, createFunctionResolvingPass()); // Resolve (...) functions
+
+ if (DisableOptimizations) return;
+
+ addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
+ addPass(PM, createCFGSimplificationPass()); // Clean up disgusting code
+ addPass(PM, createPromoteMemoryToRegister()); // Kill useless allocas
+ addPass(PM, createGlobalOptimizerPass()); // Optimize out global vars
+ addPass(PM, createGlobalDCEPass()); // Remove unused fns and globs
+ addPass(PM, createIPConstantPropagationPass());// IP Constant Propagation
+ addPass(PM, createDeadArgEliminationPass()); // Dead argument elimination
+ addPass(PM, createInstructionCombiningPass()); // Clean up after IPCP & DAE
+ addPass(PM, createCFGSimplificationPass()); // Clean up after IPCP & DAE
+
+ addPass(PM, createPruneEHPass()); // Remove dead EH info
+
+ if (!DisableInline)
+ addPass(PM, createFunctionInliningPass()); // Inline small functions
+ addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args
+
+ addPass(PM, createRaisePointerReferencesPass());// Recover type information
+ addPass(PM, createTailDuplicationPass()); // Simplify cfg by copying code
+ addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
+ addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
+ addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
+
+ addPass(PM, createReassociatePass()); // Reassociate expressions
+ addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
+ addPass(PM, createTailCallEliminationPass()); // Eliminate tail calls
+ addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
+ addPass(PM, createLICMPass()); // Hoist loop invariants
+ addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
+ addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars
+ addPass(PM, createLoopUnrollPass()); // Unroll small loops
+ addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
+ addPass(PM, createLoadValueNumberingPass()); // GVN for load instructions
+ addPass(PM, createGCSEPass()); // Remove common subexprs
+ addPass(PM, createSCCPPass()); // Constant prop with SCCP
// Run instcombine after redundancy elimination to exploit opportunities
// opened up by them.
addPass(PM, createInstructionCombiningPass());
- addPass(PM, createAggressiveDCEPass()); // SSA based 'Agressive DCE'
- addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
+ if (!DisableDSE)
+ addPass(PM, createDeadStoreEliminationPass()); // Delete dead stores
+ addPass(PM, createAggressiveDCEPass()); // SSA based 'Aggressive DCE'
+ addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
+ addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
+ addPass(PM, createConstantMergePass()); // Merge dup global constants
}
int main(int argc, char **argv) {
cl::ParseCommandLineOptions(argc, argv, " llvm .s -> .o assembler for GCC\n");
+ sys::PrintStackTraceOnErrorSignal();
std::auto_ptr<Module> M;
try {
// Parse the file now...
M.reset(ParseAssemblyFile(InputFilename));
} catch (const ParseException &E) {
- cerr << E.getMessage() << "\n";
+ std::cerr << argv[0] << ": " << E.getMessage() << "\n";
return 1;
}
if (M.get() == 0) {
- cerr << "assembly didn't read correctly.\n";
+ std::cerr << argv[0] << ": assembly didn't read correctly.\n";
return 1;
}
-
+
+ std::ostream *Out = 0;
if (OutputFilename == "") { // Didn't specify an output filename?
- std::string IFN = InputFilename;
- int Len = IFN.length();
- if (IFN[Len-2] == '.' && IFN[Len-1] == 's') { // Source ends in .s?
- OutputFilename = std::string(IFN.begin(), IFN.end()-2);
+ if (InputFilename == "-") {
+ OutputFilename = "-";
} else {
- OutputFilename = IFN; // Append a .o to it
+ std::string IFN = InputFilename;
+ int Len = IFN.length();
+ if (IFN[Len-2] == '.' && IFN[Len-1] == 's') { // Source ends in .s?
+ OutputFilename = std::string(IFN.begin(), IFN.end()-2);
+ } else {
+ OutputFilename = IFN; // Append a .o to it
+ }
+ OutputFilename += ".o";
}
- OutputFilename += ".o";
}
- std::ofstream Out(OutputFilename.c_str(), std::ios::out);
- if (!Out.good()) {
- cerr << "Error opening " << OutputFilename << "!\n";
- return 1;
+ if (OutputFilename == "-")
+ Out = &std::cout;
+ else {
+ Out = new std::ofstream(OutputFilename.c_str(), std::ios::out);
+
+ // Make sure that the Out file gets unlinked from the disk if we get a
+ // signal
+ sys::RemoveFileOnSignal(sys::Path(OutputFilename));
}
- // Make sure that the Out file gets unlink'd from the disk if we get a SIGINT
- RemoveFileOnSignal(OutputFilename);
+
+ if (!Out->good()) {
+ std::cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
+ return 1;
+ }
// In addition to just parsing the input from GCC, we also want to spiff it up
// a little bit. Do this now.
//
PassManager Passes;
+ // Add an appropriate TargetData instance for this module...
+ Passes.add(new TargetData("gccas", M.get()));
+
// Add all of the transformation passes to the pass manager to do the cleanup
// and optimization of the GCC output.
//
AddConfiguredTransformationPasses(Passes);
+ // Make sure everything is still good.
+ Passes.add(createVerifierPass());
+
// Write bytecode to file...
- Passes.add(new WriteBytecodePass(&Out));
+ Passes.add(new WriteBytecodePass(Out,false,!NoCompress));
// Run our queue of passes all at once now, efficiently.
Passes.run(*M.get());
+
+ if (Out != &std::cout) delete Out;
return 0;
}