From: Teresa Johnson <tejohnson@google.com>
Date: Mon, 19 Oct 2015 14:30:44 +0000 (+0000)
Subject: llvm-lto support for generating combined function indexes
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d6e77b7d157be995bbcc6b818c3e4a2fd8aa0ee9;p=oota-llvm.git
llvm-lto support for generating combined function indexes
Summary:
This patch adds support to llvm-lto that mirrors the support added by
r249270 to the gold plugin. This enables better testing of combined
index generation for ThinLTO.
Added a new test, and this support will be used in the test in D13515.
Reviewers: joker.eph
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D13847
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250699 91177308-0d34-0410-b5e6-96231b3b80d8
---
diff --git a/test/tools/llvm-lto/Inputs/thinlto.ll b/test/tools/llvm-lto/Inputs/thinlto.ll
new file mode 100644
index 00000000000..4e0840f3691
--- /dev/null
+++ b/test/tools/llvm-lto/Inputs/thinlto.ll
@@ -0,0 +1,4 @@
+define void @g() {
+entry:
+ ret void
+}
diff --git a/test/tools/llvm-lto/thinlto.ll b/test/tools/llvm-lto/thinlto.ll
new file mode 100644
index 00000000000..29d3881b9df
--- /dev/null
+++ b/test/tools/llvm-lto/thinlto.ll
@@ -0,0 +1,24 @@
+; Test combined function index generation for ThinLTO via llvm-lto.
+; RUN: llvm-as -function-summary %s -o %t.o
+; RUN: llvm-as -function-summary %p/Inputs/thinlto.ll -o %t2.o
+; RUN: llvm-lto -thinlto -o %t3 %t.o %t2.o
+; RUN: llvm-bcanalyzer -dump %t3.thinlto.bc | FileCheck %s --check-prefix=COMBINED
+; RUN: not test -e %t3
+
+; COMBINED: <MODULE_STRTAB_BLOCK
+; COMBINED-NEXT: <ENTRY {{.*}} record string = '{{.*}}/thinlto.ll.tmp{{.*}}.o'
+; COMBINED-NEXT: <ENTRY {{.*}} record string = '{{.*}}/thinlto.ll.tmp{{.*}}.o'
+; COMBINED-NEXT: </MODULE_STRTAB_BLOCK
+; COMBINED-NEXT: <FUNCTION_SUMMARY_BLOCK
+; COMBINED-NEXT: <COMBINED_ENTRY
+; COMBINED-NEXT: <COMBINED_ENTRY
+; COMBINED-NEXT: </FUNCTION_SUMMARY_BLOCK
+; COMBINED-NEXT: <VALUE_SYMTAB
+; COMBINED-NEXT: <COMBINED_FNENTRY {{.*}} record string = '{{f|g}}'
+; COMBINED-NEXT: <COMBINED_FNENTRY {{.*}} record string = '{{f|g}}'
+; COMBINED-NEXT: </VALUE_SYMTAB
+
+define void @f() {
+entry:
+ ret void
+}
diff --git a/tools/llvm-lto/CMakeLists.txt b/tools/llvm-lto/CMakeLists.txt
index 3ea1aeea9a4..6a35dd9a241 100644
--- a/tools/llvm-lto/CMakeLists.txt
+++ b/tools/llvm-lto/CMakeLists.txt
@@ -1,7 +1,10 @@
set(LLVM_LINK_COMPONENTS
${LLVM_TARGETS_TO_BUILD}
+ BitReader
+ Core
LTO
MC
+ Object
Support
Target
)
diff --git a/tools/llvm-lto/LLVMBuild.txt b/tools/llvm-lto/LLVMBuild.txt
index c1613a34c0e..a586db6d7f7 100644
--- a/tools/llvm-lto/LLVMBuild.txt
+++ b/tools/llvm-lto/LLVMBuild.txt
@@ -19,4 +19,4 @@
type = Tool
name = llvm-lto
parent = Tools
-required_libraries = LTO Support all-targets
+required_libraries = BitReader Core LTO Object Support all-targets
diff --git a/tools/llvm-lto/llvm-lto.cpp b/tools/llvm-lto/llvm-lto.cpp
index 50680ccb8ab..29d613f8cd2 100644
--- a/tools/llvm-lto/llvm-lto.cpp
+++ b/tools/llvm-lto/llvm-lto.cpp
@@ -13,9 +13,12 @@
//===----------------------------------------------------------------------===//
#include "llvm/ADT/StringSet.h"
+#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/CodeGen/CommandFlags.h"
+#include "llvm/IR/LLVMContext.h"
#include "llvm/LTO/LTOCodeGenerator.h"
#include "llvm/LTO/LTOModule.h"
+#include "llvm/Object/FunctionIndexObjectFile.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/ManagedStatic.h"
@@ -56,6 +59,10 @@ static cl::opt<bool>
UseDiagnosticHandler("use-diagnostic-handler", cl::init(false),
cl::desc("Use a diagnostic handler to test the handler interface"));
+static cl::opt<bool> ThinLTO(
+ "thinlto", cl::init(false),
+ cl::desc("Only write combined global index for ThinLTO backends"));
+
static cl::list<std::string>
InputFilenames(cl::Positional, cl::OneOrMore,
cl::desc("<input bitcode files>"));
@@ -151,6 +158,61 @@ static int listSymbols(StringRef Command, const TargetOptions &Options) {
return 0;
}
+/// Parse the function index out of an IR file and return the function
+/// index object if found, or nullptr if not.
+static std::unique_ptr<FunctionInfoIndex> getFunctionIndexForFile(
+ StringRef Path, std::string &Error, LLVMContext &Context) {
+ std::unique_ptr<MemoryBuffer> Buffer;
+ ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
+ MemoryBuffer::getFile(Path);
+ if (std::error_code EC = BufferOrErr.getError()) {
+ Error = EC.message();
+ return nullptr;
+ }
+ Buffer = std::move(BufferOrErr.get());
+ ErrorOr<std::unique_ptr<object::FunctionIndexObjectFile>> ObjOrErr =
+ object::FunctionIndexObjectFile::create(Buffer->getMemBufferRef(),
+ Context);
+ if (std::error_code EC = ObjOrErr.getError()) {
+ Error = EC.message();
+ return nullptr;
+ }
+ return (*ObjOrErr)->takeIndex();
+}
+
+/// Create a combined index file from the input IR files and write it.
+///
+/// This is meant to enable testing of ThinLTO combined index generation,
+/// currently available via the gold plugin via -thinlto.
+static int createCombinedFunctionIndex(StringRef Command) {
+ LLVMContext Context;
+ FunctionInfoIndex CombinedIndex;
+ uint64_t NextModuleId = 0;
+ for (auto &Filename : InputFilenames) {
+ std::string Error;
+ std::unique_ptr<FunctionInfoIndex> Index =
+ getFunctionIndexForFile(Filename, Error, Context);
+ if (!Index) {
+ errs() << Command << ": error loading file '" << Filename
+ << "': " << Error << "\n";
+ return 1;
+ }
+ CombinedIndex.mergeFrom(std::move(Index), ++NextModuleId);
+ }
+ std::error_code EC;
+ assert(!OutputFilename.empty());
+ raw_fd_ostream OS(OutputFilename + ".thinlto.bc", EC,
+ sys::fs::OpenFlags::F_None);
+ if (EC) {
+ errs() << Command << ": error opening the file '" << OutputFilename
+ << ".thinlto.bc': " << EC.message() << "\n";
+ return 1;
+ }
+ WriteFunctionSummaryToFile(&CombinedIndex, OS);
+ OS.close();
+ return 0;
+}
+
int main(int argc, char **argv) {
// Print a stack trace if we signal out.
sys::PrintStackTraceOnErrorSignal();
@@ -176,6 +238,8 @@ int main(int argc, char **argv) {
if (ListSymbolsOnly)
return listSymbols(argv[0], Options);
+ if (ThinLTO) return createCombinedFunctionIndex(argv[0]);
+
unsigned BaseArg = 0;
LTOCodeGenerator CodeGen;