Perform InstructioinCombiningPass before SampleProfile pass.

Summary: SampleProfile pass needs to be performed after InstructionCombiningPass, which helps eliminate un-inlinable function calls.

Reviewers: davidxl, dnovillo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D17742

llvm-svn: 262419

llvm/include/llvm/Transforms/InstCombine/InstCombine.h

@@ -41,6 +41,23 @@ public:
   PreservedAnalyses run(Function &F, AnalysisManager<Function> *AM);
 };
 
+/// \brief The legacy pass manager's instcombine pass.
+///
+/// This is a basic whole-function wrapper around the instcombine utility. It
+/// will try to combine all instructions in the function.
+class InstructionCombiningPass : public FunctionPass {
+  InstCombineWorklist Worklist;
+
+public:
+  static char ID; // Pass identification, replacement for typeid
+
+  InstructionCombiningPass() : FunctionPass(ID) {
+    initializeInstructionCombiningPassPass(*PassRegistry::getPassRegistry());
+  }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+  bool runOnFunction(Function &F) override;
+};
 }
 
 #endif

llvm/lib/Transforms/IPO/SampleProfile.cpp

@@ -48,6 +48,7 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/IPO.h"
 #include "llvm/Transforms/Utils/Cloning.h"
+#include "llvm/Transforms/InstCombine/InstCombine.h"
 #include <cctype>
 
 using namespace llvm;
@@ -121,7 +122,7 @@ public:
   bool runOnModule(Module &M) override;
 
   void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.setPreservesCFG();
+    AU.addRequired<InstructionCombiningPass>();
   }
 
 protected:
@@ -1215,6 +1216,7 @@ char SampleProfileLoader::ID = 0;
 INITIALIZE_PASS_BEGIN(SampleProfileLoader, "sample-profile",
                       "Sample Profile loader", false, false)
 INITIALIZE_PASS_DEPENDENCY(AddDiscriminators)
+INITIALIZE_PASS_DEPENDENCY(InstructionCombiningPass)
 INITIALIZE_PASS_END(SampleProfileLoader, "sample-profile",
                     "Sample Profile loader", false, false)
 
@@ -1258,6 +1260,7 @@ bool SampleProfileLoader::runOnModule(Module &M) {
 
 bool SampleProfileLoader::runOnFunction(Function &F) {
   F.setEntryCount(0);
+  getAnalysis<InstructionCombiningPass>(F);
   Samples = Reader->getSamplesFor(F);
   if (!Samples->empty())
     return emitAnnotations(F);

llvm/lib/Transforms/InstCombine/InstructionCombining.cpp

@@ -3078,26 +3078,6 @@ PreservedAnalyses InstCombinePass::run(Function &F,
   return PA;
 }
 
-namespace {
-/// \brief The legacy pass manager's instcombine pass.
-///
-/// This is a basic whole-function wrapper around the instcombine utility. It
-/// will try to combine all instructions in the function.
-class InstructionCombiningPass : public FunctionPass {
-  InstCombineWorklist Worklist;
-
-public:
-  static char ID; // Pass identification, replacement for typeid
-
-  InstructionCombiningPass() : FunctionPass(ID) {
-    initializeInstructionCombiningPassPass(*PassRegistry::getPassRegistry());
-  }
-
-  void getAnalysisUsage(AnalysisUsage &AU) const override;
-  bool runOnFunction(Function &F) override;
-};
-}
-
 void InstructionCombiningPass::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.setPreservesCFG();
   AU.addRequired<AAResultsWrapperPass>();

llvm/test/Transforms/SampleProfile/Inputs/inline-combine.prof

@@ -0,0 +1,2 @@
+foo:1000:1000
+ 1: bar:1000

llvm/test/Transforms/SampleProfile/calls.ll

@@ -63,8 +63,8 @@ while.body:                                       ; preds = %while.cond
 ; both branches out of while.body had the same weight. In reality,
 ; the edge while.body->if.then is taken most of the time.
 ;
-; CHECK: edge while.body -> if.then probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
 ; CHECK: edge while.body -> if.else probability is 0x00000000 / 0x80000000 = 0.00%
+; CHECK: edge while.body -> if.then probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
 
 
 if.then:                                          ; preds = %while.body

llvm/test/Transforms/SampleProfile/cov-zero-samples.ll

@@ -1,6 +1,6 @@
 ; RUN: opt < %s -sample-profile -sample-profile-file=%S/Inputs/cov-zero-samples.prof -sample-profile-check-record-coverage=100 -pass-remarks=sample-profile -o /dev/null 2>&1 | FileCheck %s
 ;
-; CHECK: remark: cov-zero-samples.cc:9:25: Applied 404065 samples from profile (offset: 2.1)
+; CHECK: remark: cov-zero-samples.cc:9:29: Applied 404065 samples from profile (offset: 2.1)
 ; CHECK: remark: cov-zero-samples.cc:10:9: Applied 443089 samples from profile (offset: 3)
 ; CHECK: remark: cov-zero-samples.cc:10:36: Applied 0 samples from profile (offset: 3.1)
 ; CHECK: remark: cov-zero-samples.cc:11:12: Applied 404066 samples from profile (offset: 4)

llvm/test/Transforms/SampleProfile/inline-combine.ll

@@ -0,0 +1,44 @@
+; RUN: opt < %s -sample-profile -sample-profile-file=%S/Inputs/inline-combine.prof -S | FileCheck %s
+
+%"class.llvm::FoldingSetNodeID" = type { %"class.llvm::SmallVector" }
+%"class.llvm::SmallVector" = type { %"class.llvm::SmallVectorImpl.base", %"struct.llvm::SmallVectorStorage" }
+%"class.llvm::SmallVectorImpl.base" = type { %"class.llvm::SmallVectorTemplateBase.base" }
+%"class.llvm::SmallVectorTemplateBase.base" = type { %"class.llvm::SmallVectorTemplateCommon.base" }
+%"class.llvm::SmallVectorTemplateCommon.base" = type <{ %"class.llvm::SmallVectorBase", %"struct.llvm::AlignedCharArrayUnion" }>
+%"class.llvm::SmallVectorBase" = type { i8*, i8*, i8* }
+%"struct.llvm::AlignedCharArrayUnion" = type { %"struct.llvm::AlignedCharArray" }
+%"struct.llvm::AlignedCharArray" = type { [4 x i8] }
+%"struct.llvm::SmallVectorStorage" = type { [31 x %"struct.llvm::AlignedCharArrayUnion"] }
+%"class.llvm::SmallVectorImpl" = type { %"class.llvm::SmallVectorTemplateBase.base", [4 x i8] }
+
+$foo = comdat any
+
+$bar = comdat any
+
+define void @foo(%"class.llvm::FoldingSetNodeID"* %this) comdat align 2 !dbg !3 {
+  %1 = alloca %"class.llvm::FoldingSetNodeID"*, align 8
+  store %"class.llvm::FoldingSetNodeID"* %this, %"class.llvm::FoldingSetNodeID"** %1, align 8
+  %2 = load %"class.llvm::FoldingSetNodeID"*, %"class.llvm::FoldingSetNodeID"** %1, align 8
+  %3 = getelementptr inbounds %"class.llvm::FoldingSetNodeID", %"class.llvm::FoldingSetNodeID"* %2, i32 0, i32 0
+; the call should have been inlined after sample-profile pass
+; CHECK-NOT: call
+  call void bitcast (void (%"class.llvm::SmallVectorImpl"*)* @bar to void (%"class.llvm::SmallVector"*)*)(%"class.llvm::SmallVector"* %3), !dbg !7
+  ret void
+}
+
+define void @bar(%"class.llvm::SmallVectorImpl"* %this) comdat align 2 !dbg !8 {
+  ret void
+}
+
+!llvm.module.flags = !{!0, !1}
+!llvm.ident = !{!2}
+
+!0 = !{i32 2, !"Dwarf Version", i32 4}
+!1 = !{i32 1, !"Debug Info Version", i32 3}
+!2 = !{!"clang version 3.5 "}
+!3 = distinct !DISubprogram(name: "foo", scope: !4, file: !4, line: 3, type: !5, isLocal: false, isDefinition: true, scopeLine: 3, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, variables: !6)
+!4 = !DIFile(filename: "test.cc", directory: ".")
+!5 = !DISubroutineType(types: !6)
+!6 = !{}
+!7 = !DILocation(line: 4, scope: !3)
+!8 = distinct !DISubprogram(name: "bar", scope: !4, file: !4, line: 7, type: !5, isLocal: false, isDefinition: true, scopeLine: 7, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, variables: !6)

llvm/test/Transforms/SampleProfile/inline-coverage.ll

@@ -16,7 +16,7 @@
 ;    12    }
 ;
 ; CHECK: remark: coverage.cc:10:12: inlined hot callee '_Z3fool' with 172746 samples into 'main'
-; CHECK: remark: coverage.cc:9:19: Applied 23478 samples from profile (offset: 2.1)
+; CHECK: remark: coverage.cc:9:21: Applied 23478 samples from profile (offset: 2.1)
 ; CHECK: remark: coverage.cc:10:16: Applied 23478 samples from profile (offset: 3)
 ; CHECK: remark: coverage.cc:4:10: Applied 31878 samples from profile (offset: 1)
 ; CHECK: remark: coverage.cc:11:10: Applied 0 samples from profile (offset: 4)