rust/src/rustllvm/RustWrapper.cpp

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// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#include "rustllvm.h"
rustc: Optimize reading metadata by 4x We were previously reading metadata via `ar p`, but as learned from rustdoc awhile back, spawning a process to do something is pretty slow. Turns out LLVM has an Archive class to read archives, but it cannot write archives. This commits adds bindings to the read-only version of the LLVM archive class (with a new type that only has a read() method), and then it uses this class when reading the metadata out of rlibs. When you put this in tandem of not compressing the metadata, reading the metadata is 4x faster than it used to be The timings I got for reading metadata from the respective libraries was: libstd-04ff901e-0.9-pre.dylib => 100ms libstd-04ff901e-0.9-pre.rlib => 23ms librustuv-7945354c-0.9-pre.dylib => 4ms librustuv-7945354c-0.9-pre.rlib => 1ms librustc-5b94a16f-0.9-pre.dylib => 87ms librustc-5b94a16f-0.9-pre.rlib => 35ms libextra-a6ebb16f-0.9-pre.dylib => 63ms libextra-a6ebb16f-0.9-pre.rlib => 15ms libsyntax-2e4c0458-0.9-pre.dylib => 86ms libsyntax-2e4c0458-0.9-pre.rlib => 22ms In order to always take advantage of these faster metadata read-times, I sort the files in filesearch based on whether they have an rlib extension or not (prefer all rlib files first). Overall, this halved the compile time for a `fn main() {}` crate from 0.185s to 0.095s on my system (when preferring dynamic linking). Reading metadata is still the slowest pass of the compiler at 0.035s, but it's getting pretty close to linking at 0.021s! The next best optimization is to just not copy the metadata from LLVM because that's the most expensive part of reading metadata right now.
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#include "llvm/Object/Archive.h"
//===----------------------------------------------------------------------===
//
// This file defines alternate interfaces to core functions that are more
// readily callable by Rust's FFI.
//
//===----------------------------------------------------------------------===
using namespace llvm;
using namespace llvm::sys;
rustc: Optimize reading metadata by 4x We were previously reading metadata via `ar p`, but as learned from rustdoc awhile back, spawning a process to do something is pretty slow. Turns out LLVM has an Archive class to read archives, but it cannot write archives. This commits adds bindings to the read-only version of the LLVM archive class (with a new type that only has a read() method), and then it uses this class when reading the metadata out of rlibs. When you put this in tandem of not compressing the metadata, reading the metadata is 4x faster than it used to be The timings I got for reading metadata from the respective libraries was: libstd-04ff901e-0.9-pre.dylib => 100ms libstd-04ff901e-0.9-pre.rlib => 23ms librustuv-7945354c-0.9-pre.dylib => 4ms librustuv-7945354c-0.9-pre.rlib => 1ms librustc-5b94a16f-0.9-pre.dylib => 87ms librustc-5b94a16f-0.9-pre.rlib => 35ms libextra-a6ebb16f-0.9-pre.dylib => 63ms libextra-a6ebb16f-0.9-pre.rlib => 15ms libsyntax-2e4c0458-0.9-pre.dylib => 86ms libsyntax-2e4c0458-0.9-pre.rlib => 22ms In order to always take advantage of these faster metadata read-times, I sort the files in filesearch based on whether they have an rlib extension or not (prefer all rlib files first). Overall, this halved the compile time for a `fn main() {}` crate from 0.185s to 0.095s on my system (when preferring dynamic linking). Reading metadata is still the slowest pass of the compiler at 0.035s, but it's getting pretty close to linking at 0.021s! The next best optimization is to just not copy the metadata from LLVM because that's the most expensive part of reading metadata right now.
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using namespace llvm::object;
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const char *LLVMRustError;
extern "C" LLVMMemoryBufferRef
LLVMRustCreateMemoryBufferWithContentsOfFile(const char *Path) {
LLVMMemoryBufferRef MemBuf = NULL;
LLVMCreateMemoryBufferWithContentsOfFile(Path, &MemBuf,
const_cast<char **>(&LLVMRustError));
return MemBuf;
}
extern "C" const char *LLVMRustGetLastError(void) {
return LLVMRustError;
}
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extern "C" void
LLVMRustSetNormalizedTarget(LLVMModuleRef M, const char *triple) {
unwrap(M)->setTargetTriple(Triple::normalize(triple));
}
extern "C" LLVMValueRef LLVMRustConstSmallInt(LLVMTypeRef IntTy, unsigned N,
LLVMBool SignExtend) {
return LLVMConstInt(IntTy, (unsigned long long)N, SignExtend);
}
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extern "C" LLVMValueRef LLVMRustConstInt(LLVMTypeRef IntTy,
unsigned N_hi,
unsigned N_lo,
LLVMBool SignExtend) {
unsigned long long N = N_hi;
N <<= 32;
N |= N_lo;
return LLVMConstInt(IntTy, N, SignExtend);
}
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extern "C" void LLVMRustPrintPassTimings() {
raw_fd_ostream OS (2, false); // stderr.
TimerGroup::printAll(OS);
}
extern "C" LLVMValueRef LLVMGetOrInsertFunction(LLVMModuleRef M,
const char* Name,
LLVMTypeRef FunctionTy) {
return wrap(unwrap(M)->getOrInsertFunction(Name,
unwrap<FunctionType>(FunctionTy)));
}
extern "C" LLVMTypeRef LLVMMetadataTypeInContext(LLVMContextRef C) {
return wrap(Type::getMetadataTy(*unwrap(C)));
}
extern "C" void LLVMAddFunctionAttrString(LLVMValueRef fn, const char *Name) {
unwrap<Function>(fn)->addFnAttr(Name);
}
extern "C" void LLVMAddReturnAttribute(LLVMValueRef Fn, LLVMAttribute PA) {
Function *A = unwrap<Function>(Fn);
AttrBuilder B(PA);
A->addAttributes(AttributeSet::ReturnIndex,
AttributeSet::get(A->getContext(), AttributeSet::ReturnIndex, B));
}
extern "C" void LLVMRemoveReturnAttribute(LLVMValueRef Fn, LLVMAttribute PA) {
Function *A = unwrap<Function>(Fn);
AttrBuilder B(PA);
A->removeAttributes(AttributeSet::ReturnIndex,
AttributeSet::get(A->getContext(), AttributeSet::ReturnIndex, B));
}
extern "C" void LLVMAddColdAttribute(LLVMValueRef Fn) {
Function *A = unwrap<Function>(Fn);
A->addAttribute(AttributeSet::FunctionIndex, Attribute::Cold);
}
extern "C" LLVMValueRef LLVMBuildAtomicLoad(LLVMBuilderRef B,
LLVMValueRef source,
const char* Name,
AtomicOrdering order,
unsigned alignment) {
LoadInst* li = new LoadInst(unwrap(source),0);
li->setVolatile(true);
li->setAtomic(order);
li->setAlignment(alignment);
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return wrap(unwrap(B)->Insert(li, Name));
}
extern "C" LLVMValueRef LLVMBuildAtomicStore(LLVMBuilderRef B,
LLVMValueRef val,
LLVMValueRef target,
AtomicOrdering order,
unsigned alignment) {
StoreInst* si = new StoreInst(unwrap(val),unwrap(target));
si->setVolatile(true);
si->setAtomic(order);
si->setAlignment(alignment);
return wrap(unwrap(B)->Insert(si));
}
extern "C" LLVMValueRef LLVMBuildAtomicCmpXchg(LLVMBuilderRef B,
LLVMValueRef target,
LLVMValueRef old,
LLVMValueRef source,
AtomicOrdering order) {
return wrap(unwrap(B)->CreateAtomicCmpXchg(unwrap(target), unwrap(old),
unwrap(source), order));
}
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extern "C" LLVMValueRef LLVMBuildAtomicFence(LLVMBuilderRef B, AtomicOrdering order) {
return wrap(unwrap(B)->CreateFence(order));
}
extern "C" void LLVMSetDebug(int Enabled) {
#ifndef NDEBUG
DebugFlag = Enabled;
#endif
}
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extern "C" LLVMValueRef LLVMInlineAsm(LLVMTypeRef Ty,
char *AsmString,
char *Constraints,
LLVMBool HasSideEffects,
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LLVMBool IsAlignStack,
unsigned Dialect) {
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return wrap(InlineAsm::get(unwrap<FunctionType>(Ty), AsmString,
Constraints, HasSideEffects,
IsAlignStack, (InlineAsm::AsmDialect) Dialect));
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}
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typedef DIBuilder* DIBuilderRef;
template<typename DIT>
DIT unwrapDI(LLVMValueRef ref) {
return DIT(ref ? unwrap<MDNode>(ref) : NULL);
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}
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extern "C" DIBuilderRef LLVMDIBuilderCreate(LLVMModuleRef M) {
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return new DIBuilder(*unwrap(M));
}
extern "C" void LLVMDIBuilderDispose(DIBuilderRef Builder) {
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delete Builder;
}
extern "C" void LLVMDIBuilderFinalize(DIBuilderRef Builder) {
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Builder->finalize();
}
extern "C" void LLVMDIBuilderCreateCompileUnit(
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DIBuilderRef Builder,
unsigned Lang,
const char* File,
const char* Dir,
const char* Producer,
bool isOptimized,
const char* Flags,
unsigned RuntimeVer,
const char* SplitName) {
Builder->createCompileUnit(Lang, File, Dir, Producer, isOptimized,
Flags, RuntimeVer, SplitName);
}
extern "C" LLVMValueRef LLVMDIBuilderCreateFile(
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DIBuilderRef Builder,
const char* Filename,
const char* Directory) {
return wrap(Builder->createFile(Filename, Directory));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateSubroutineType(
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DIBuilderRef Builder,
LLVMValueRef File,
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LLVMValueRef ParameterTypes) {
return wrap(Builder->createSubroutineType(
unwrapDI<DIFile>(File),
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unwrapDI<DIArray>(ParameterTypes)));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateFunction(
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DIBuilderRef Builder,
LLVMValueRef Scope,
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const char* Name,
const char* LinkageName,
LLVMValueRef File,
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unsigned LineNo,
LLVMValueRef Ty,
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bool isLocalToUnit,
bool isDefinition,
unsigned ScopeLine,
unsigned Flags,
bool isOptimized,
LLVMValueRef Fn,
LLVMValueRef TParam,
LLVMValueRef Decl) {
return wrap(Builder->createFunction(
unwrapDI<DIScope>(Scope), Name, LinkageName,
unwrapDI<DIFile>(File), LineNo,
unwrapDI<DICompositeType>(Ty), isLocalToUnit, isDefinition, ScopeLine,
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Flags, isOptimized,
unwrap<Function>(Fn),
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unwrapDI<MDNode*>(TParam),
unwrapDI<MDNode*>(Decl)));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateBasicType(
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DIBuilderRef Builder,
const char* Name,
uint64_t SizeInBits,
uint64_t AlignInBits,
unsigned Encoding) {
return wrap(Builder->createBasicType(
Name, SizeInBits,
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AlignInBits, Encoding));
}
extern "C" LLVMValueRef LLVMDIBuilderCreatePointerType(
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DIBuilderRef Builder,
LLVMValueRef PointeeTy,
uint64_t SizeInBits,
uint64_t AlignInBits,
const char* Name) {
return wrap(Builder->createPointerType(
unwrapDI<DIType>(PointeeTy), SizeInBits, AlignInBits, Name));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateStructType(
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DIBuilderRef Builder,
LLVMValueRef Scope,
const char* Name,
LLVMValueRef File,
unsigned LineNumber,
uint64_t SizeInBits,
uint64_t AlignInBits,
unsigned Flags,
LLVMValueRef DerivedFrom,
LLVMValueRef Elements,
unsigned RunTimeLang,
LLVMValueRef VTableHolder,
const char *UniqueId) {
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return wrap(Builder->createStructType(
unwrapDI<DIDescriptor>(Scope),
Name,
unwrapDI<DIFile>(File),
LineNumber,
SizeInBits,
AlignInBits,
Flags,
unwrapDI<DIType>(DerivedFrom),
unwrapDI<DIArray>(Elements),
RunTimeLang,
unwrapDI<DIType>(VTableHolder),
UniqueId));
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}
extern "C" LLVMValueRef LLVMDIBuilderCreateMemberType(
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DIBuilderRef Builder,
LLVMValueRef Scope,
const char* Name,
LLVMValueRef File,
unsigned LineNo,
uint64_t SizeInBits,
uint64_t AlignInBits,
uint64_t OffsetInBits,
unsigned Flags,
LLVMValueRef Ty) {
return wrap(Builder->createMemberType(
unwrapDI<DIDescriptor>(Scope), Name,
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unwrapDI<DIFile>(File), LineNo,
SizeInBits, AlignInBits, OffsetInBits, Flags,
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unwrapDI<DIType>(Ty)));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateLexicalBlock(
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DIBuilderRef Builder,
LLVMValueRef Scope,
LLVMValueRef File,
unsigned Line,
unsigned Col) {
return wrap(Builder->createLexicalBlock(
unwrapDI<DIDescriptor>(Scope),
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unwrapDI<DIFile>(File), Line, Col));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateLocalVariable(
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DIBuilderRef Builder,
unsigned Tag,
LLVMValueRef Scope,
const char* Name,
LLVMValueRef File,
unsigned LineNo,
LLVMValueRef Ty,
bool AlwaysPreserve,
unsigned Flags,
unsigned ArgNo) {
return wrap(Builder->createLocalVariable(Tag,
unwrapDI<DIDescriptor>(Scope), Name,
unwrapDI<DIFile>(File),
LineNo,
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unwrapDI<DIType>(Ty), AlwaysPreserve, Flags, ArgNo));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateArrayType(
DIBuilderRef Builder,
uint64_t Size,
uint64_t AlignInBits,
LLVMValueRef Ty,
LLVMValueRef Subscripts) {
return wrap(Builder->createArrayType(Size, AlignInBits,
unwrapDI<DIType>(Ty),
unwrapDI<DIArray>(Subscripts)));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateVectorType(
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DIBuilderRef Builder,
uint64_t Size,
uint64_t AlignInBits,
LLVMValueRef Ty,
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LLVMValueRef Subscripts) {
return wrap(Builder->createVectorType(Size, AlignInBits,
unwrapDI<DIType>(Ty),
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unwrapDI<DIArray>(Subscripts)));
}
extern "C" LLVMValueRef LLVMDIBuilderGetOrCreateSubrange(
DIBuilderRef Builder,
int64_t Lo,
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int64_t Count) {
return wrap(Builder->getOrCreateSubrange(Lo, Count));
}
extern "C" LLVMValueRef LLVMDIBuilderGetOrCreateArray(
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DIBuilderRef Builder,
LLVMValueRef* Ptr,
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unsigned Count) {
return wrap(Builder->getOrCreateArray(
ArrayRef<Value*>(reinterpret_cast<Value**>(Ptr), Count)));
}
extern "C" LLVMValueRef LLVMDIBuilderInsertDeclareAtEnd(
DIBuilderRef Builder,
LLVMValueRef Val,
LLVMValueRef VarInfo,
LLVMBasicBlockRef InsertAtEnd) {
return wrap(Builder->insertDeclare(
unwrap(Val),
unwrapDI<DIVariable>(VarInfo),
unwrap(InsertAtEnd)));
}
extern "C" LLVMValueRef LLVMDIBuilderInsertDeclareBefore(
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DIBuilderRef Builder,
LLVMValueRef Val,
LLVMValueRef VarInfo,
LLVMValueRef InsertBefore) {
return wrap(Builder->insertDeclare(
unwrap(Val),
unwrapDI<DIVariable>(VarInfo),
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unwrap<Instruction>(InsertBefore)));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateEnumerator(
DIBuilderRef Builder,
const char* Name,
uint64_t Val)
{
return wrap(Builder->createEnumerator(Name, Val));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateEnumerationType(
DIBuilderRef Builder,
LLVMValueRef Scope,
const char* Name,
LLVMValueRef File,
unsigned LineNumber,
uint64_t SizeInBits,
uint64_t AlignInBits,
LLVMValueRef Elements,
LLVMValueRef ClassType)
{
return wrap(Builder->createEnumerationType(
unwrapDI<DIDescriptor>(Scope),
Name,
unwrapDI<DIFile>(File),
LineNumber,
SizeInBits,
AlignInBits,
unwrapDI<DIArray>(Elements),
unwrapDI<DIType>(ClassType)));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateUnionType(
DIBuilderRef Builder,
LLVMValueRef Scope,
const char* Name,
LLVMValueRef File,
unsigned LineNumber,
uint64_t SizeInBits,
uint64_t AlignInBits,
unsigned Flags,
LLVMValueRef Elements,
unsigned RunTimeLang,
const char* UniqueId)
{
return wrap(Builder->createUnionType(
unwrapDI<DIDescriptor>(Scope),
Name,
unwrapDI<DIFile>(File),
LineNumber,
SizeInBits,
AlignInBits,
Flags,
unwrapDI<DIArray>(Elements),
RunTimeLang,
UniqueId));
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}
extern "C" void LLVMSetUnnamedAddr(LLVMValueRef Value, LLVMBool Unnamed) {
unwrap<GlobalValue>(Value)->setUnnamedAddr(Unnamed);
}
extern "C" LLVMValueRef LLVMDIBuilderCreateTemplateTypeParameter(
DIBuilderRef Builder,
LLVMValueRef Scope,
const char* Name,
LLVMValueRef Ty,
LLVMValueRef File,
unsigned LineNo,
unsigned ColumnNo)
{
return wrap(Builder->createTemplateTypeParameter(
unwrapDI<DIDescriptor>(Scope),
Name,
unwrapDI<DIType>(Ty),
unwrapDI<MDNode*>(File),
LineNo,
ColumnNo));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateOpDeref(LLVMTypeRef IntTy)
{
return LLVMConstInt(IntTy, DIBuilder::OpDeref, true);
}
extern "C" LLVMValueRef LLVMDIBuilderCreateOpPlus(LLVMTypeRef IntTy)
{
return LLVMConstInt(IntTy, DIBuilder::OpPlus, true);
}
extern "C" LLVMValueRef LLVMDIBuilderCreateComplexVariable(
DIBuilderRef Builder,
unsigned Tag,
LLVMValueRef Scope,
const char *Name,
LLVMValueRef File,
unsigned LineNo,
LLVMValueRef Ty,
LLVMValueRef* AddrOps,
unsigned AddrOpsCount,
unsigned ArgNo)
{
llvm::ArrayRef<llvm::Value*> addr_ops((llvm::Value**)AddrOps, AddrOpsCount);
return wrap(Builder->createComplexVariable(
Tag,
unwrapDI<DIDescriptor>(Scope),
Name,
unwrapDI<DIFile>(File),
LineNo,
unwrapDI<DIType>(Ty),
addr_ops,
ArgNo
));
}
extern "C" LLVMValueRef LLVMDIBuilderCreateNameSpace(
DIBuilderRef Builder,
LLVMValueRef Scope,
const char* Name,
LLVMValueRef File,
unsigned LineNo)
{
return wrap(Builder->createNameSpace(
unwrapDI<DIDescriptor>(Scope),
Name,
unwrapDI<DIFile>(File),
LineNo));
}
extern "C" void LLVMDICompositeTypeSetTypeArray(
LLVMValueRef CompositeType,
LLVMValueRef TypeArray)
{
unwrapDI<DICompositeType>(CompositeType).setTypeArray(unwrapDI<DIArray>(TypeArray));
}
extern "C" char *LLVMTypeToString(LLVMTypeRef Type) {
std::string s;
llvm::raw_string_ostream os(s);
unwrap<llvm::Type>(Type)->print(os);
return strdup(os.str().data());
}
Implement LTO This commit implements LTO for rust leveraging LLVM's passes. What this means is: * When compiling an rlib, in addition to insdering foo.o into the archive, also insert foo.bc (the LLVM bytecode) of the optimized module. * When the compiler detects the -Z lto option, it will attempt to perform LTO on a staticlib or binary output. The compiler will emit an error if a dylib or rlib output is being generated. * The actual act of performing LTO is as follows: 1. Force all upstream libraries to have an rlib version available. 2. Load the bytecode of each upstream library from the rlib. 3. Link all this bytecode into the current LLVM module (just using llvm apis) 4. Run an internalization pass which internalizes all symbols except those found reachable for the local crate of compilation. 5. Run the LLVM LTO pass manager over this entire module 6a. If assembling an archive, then add all upstream rlibs into the output archive. This ignores all of the object/bitcode/metadata files rust generated and placed inside the rlibs. 6b. If linking a binary, create copies of all upstream rlibs, remove the rust-generated object-file, and then link everything as usual. As I have explained in #10741, this process is excruciatingly slow, so this is *not* turned on by default, and it is also why I have decided to hide it behind a -Z flag for now. The good news is that the binary sizes are about as small as they can be as a result of LTO, so it's definitely working. Closes #10741 Closes #10740
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extern "C" char *LLVMValueToString(LLVMValueRef Value) {
std::string s;
llvm::raw_string_ostream os(s);
os << "(";
unwrap<llvm::Value>(Value)->getType()->print(os);
os << ":";
unwrap<llvm::Value>(Value)->print(os);
os << ")";
return strdup(os.str().data());
}
Implement LTO This commit implements LTO for rust leveraging LLVM's passes. What this means is: * When compiling an rlib, in addition to insdering foo.o into the archive, also insert foo.bc (the LLVM bytecode) of the optimized module. * When the compiler detects the -Z lto option, it will attempt to perform LTO on a staticlib or binary output. The compiler will emit an error if a dylib or rlib output is being generated. * The actual act of performing LTO is as follows: 1. Force all upstream libraries to have an rlib version available. 2. Load the bytecode of each upstream library from the rlib. 3. Link all this bytecode into the current LLVM module (just using llvm apis) 4. Run an internalization pass which internalizes all symbols except those found reachable for the local crate of compilation. 5. Run the LLVM LTO pass manager over this entire module 6a. If assembling an archive, then add all upstream rlibs into the output archive. This ignores all of the object/bitcode/metadata files rust generated and placed inside the rlibs. 6b. If linking a binary, create copies of all upstream rlibs, remove the rust-generated object-file, and then link everything as usual. As I have explained in #10741, this process is excruciatingly slow, so this is *not* turned on by default, and it is also why I have decided to hide it behind a -Z flag for now. The good news is that the binary sizes are about as small as they can be as a result of LTO, so it's definitely working. Closes #10741 Closes #10740
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extern "C" bool
LLVMRustLinkInExternalBitcode(LLVMModuleRef dst, char *bc, size_t len) {
Module *Dst = unwrap(dst);
MemoryBuffer* buf = MemoryBuffer::getMemBufferCopy(StringRef(bc, len));
std::string Err;
Module *Src = llvm::getLazyBitcodeModule(buf, Dst->getContext(), &Err);
if (Src == NULL) {
LLVMRustError = Err.c_str();
delete buf;
return false;
}
if (Linker::LinkModules(Dst, Src, Linker::DestroySource, &Err)) {
LLVMRustError = Err.c_str();
return false;
}
return true;
}
rustc: Optimize reading metadata by 4x We were previously reading metadata via `ar p`, but as learned from rustdoc awhile back, spawning a process to do something is pretty slow. Turns out LLVM has an Archive class to read archives, but it cannot write archives. This commits adds bindings to the read-only version of the LLVM archive class (with a new type that only has a read() method), and then it uses this class when reading the metadata out of rlibs. When you put this in tandem of not compressing the metadata, reading the metadata is 4x faster than it used to be The timings I got for reading metadata from the respective libraries was: libstd-04ff901e-0.9-pre.dylib => 100ms libstd-04ff901e-0.9-pre.rlib => 23ms librustuv-7945354c-0.9-pre.dylib => 4ms librustuv-7945354c-0.9-pre.rlib => 1ms librustc-5b94a16f-0.9-pre.dylib => 87ms librustc-5b94a16f-0.9-pre.rlib => 35ms libextra-a6ebb16f-0.9-pre.dylib => 63ms libextra-a6ebb16f-0.9-pre.rlib => 15ms libsyntax-2e4c0458-0.9-pre.dylib => 86ms libsyntax-2e4c0458-0.9-pre.rlib => 22ms In order to always take advantage of these faster metadata read-times, I sort the files in filesearch based on whether they have an rlib extension or not (prefer all rlib files first). Overall, this halved the compile time for a `fn main() {}` crate from 0.185s to 0.095s on my system (when preferring dynamic linking). Reading metadata is still the slowest pass of the compiler at 0.035s, but it's getting pretty close to linking at 0.021s! The next best optimization is to just not copy the metadata from LLVM because that's the most expensive part of reading metadata right now.
2013-12-16 22:58:21 -06:00
extern "C" void*
LLVMRustOpenArchive(char *path) {
OwningPtr<MemoryBuffer> buf;
error_code err = MemoryBuffer::getFile(path, buf);
if (err) {
LLVMRustError = err.message().c_str();
return NULL;
}
Archive *ret = new Archive(buf.take(), err);
if (err) {
LLVMRustError = err.message().c_str();
return NULL;
}
return ret;
}
extern "C" const char*
LLVMRustArchiveReadSection(Archive *ar, char *name, size_t *size) {
for (Archive::child_iterator child = ar->begin_children(),
end = ar->end_children();
child != end; ++child) {
StringRef sect_name;
error_code err = child->getName(sect_name);
if (err) continue;
if (sect_name.trim(" ") == name) {
StringRef buf = child->getBuffer();
*size = buf.size();
return buf.data();
}
}
return NULL;
}
extern "C" void
LLVMRustDestroyArchive(Archive *ar) {
delete ar;
}