Index: include/llvm/IR/Function.h
===================================================================
--- include/llvm/IR/Function.h
+++ include/llvm/IR/Function.h
@@ -141,6 +141,9 @@
// Provide fast operand accessors.
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
+ /// Returns the number of IR instructions contained in the \p Function.
+ int getFunctionInstrCount();
+
/// Returns the FunctionType for me.
FunctionType *getFunctionType() const {
return cast<FunctionType>(getValueType());
Index: include/llvm/IR/LegacyPassManagers.h
===================================================================
--- include/llvm/IR/LegacyPassManagers.h
+++ include/llvm/IR/LegacyPassManagers.h
@@ -403,6 +403,14 @@
InheritedAnalysis[Index++] = (*I)->getAvailableAnalysis();
}
+ /// Return the total number of IR instructions in \p M.
+ int getModuleInstrCount(Module &M);
+
+ /// \brief Emit a remark signifying that the number of IR instructions in the
+ /// module changed.
+ void emitIRSizeChangedRemark(Pass *P, Module &M, const int &OriginalCount,
+ const int &FinalCount);
+
protected:
// Top level manager.
PMTopLevelManager *TPM;
Index: include/llvm/IR/Module.h
===================================================================
--- include/llvm/IR/Module.h
+++ include/llvm/IR/Module.h
@@ -207,6 +207,9 @@
/// @returns the module identifier as a string
const std::string &getModuleIdentifier() const { return ModuleID; }
+ /// Return the number of IR instructions contained in the module.
+ int getModuleInstrCount();
+
/// Get the module's original source file name. When compiling from
/// bitcode, this is taken from a bitcode record where it was recorded.
/// For other compiles it is the same as the ModuleID, which would
Index: lib/Analysis/CallGraphSCCPass.cpp
===================================================================
--- lib/Analysis/CallGraphSCCPass.cpp
+++ lib/Analysis/CallGraphSCCPass.cpp
@@ -120,7 +120,7 @@
bool &DevirtualizedCall) {
bool Changed = false;
PMDataManager *PM = P->getAsPMDataManager();
-
+ Module &M = CG.getModule();
if (!PM) {
CallGraphSCCPass *CGSP = (CallGraphSCCPass*)P;
if (!CallGraphUpToDate) {
@@ -130,7 +130,13 @@
{
TimeRegion PassTimer(getPassTimer(CGSP));
+
+ // Remember the number of instructions in the module before the pass.
+ int OriginalCount = M.getModuleInstrCount();
Changed = CGSP->runOnSCC(CurSCC);
+ // If the pass modified the size of the module, emit a remark.
+ emitIRSizeChangedRemark(P, M, OriginalCount, M.getModuleInstrCount());
+
}
// After the CGSCCPass is done, when assertions are enabled, use
@@ -147,13 +153,26 @@
"Invalid CGPassManager member");
FPPassManager *FPP = (FPPassManager*)P;
+ // Keep track of the original module size.
+ int ModuleCount = M.getModuleInstrCount();
+
// Run pass P on all functions in the current SCC.
for (CallGraphNode *CGN : CurSCC) {
if (Function *F = CGN->getFunction()) {
dumpPassInfo(P, EXECUTION_MSG, ON_FUNCTION_MSG, F->getName());
{
TimeRegion PassTimer(getPassTimer(FPP));
- Changed |= FPP->runOnFunction(*F);
+ int OrigFnCount = F->getFunctionInstrCount();
+
+ // Run FPP on F and check if it changed anything.
+ if (FPP->runOnFunction(*F)) {
+ // It changed something. Keep track of it and also emit a remark if
+ // it changed the size of the module.
+ Changed = true;
+ int InstrDiff = F->getFunctionInstrCount() - OrigFnCount;
+ emitIRSizeChangedRemark(P, M, ModuleCount, ModuleCount + InstrDiff);
+ ModuleCount += InstrDiff;
+ }
}
F->getContext().yield();
}
Index: lib/IR/Function.cpp
===================================================================
--- lib/IR/Function.cpp
+++ lib/IR/Function.cpp
@@ -195,6 +195,13 @@
return getType()->getContext();
}
+int Function::getFunctionInstrCount() {
+ int IRCount = 0;
+ for (BasicBlock &BB : BasicBlocks)
+ IRCount += BB.size();
+ return IRCount;
+}
+
void Function::removeFromParent() {
getParent()->getFunctionList().remove(getIterator());
}
Index: lib/IR/LegacyPassManager.cpp
===================================================================
--- lib/IR/LegacyPassManager.cpp
+++ lib/IR/LegacyPassManager.cpp
@@ -13,6 +13,7 @@
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/IRPrintingPasses.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/LegacyPassManagers.h"
@@ -128,8 +129,33 @@
return PassDebugging >= Executions;
}
-
-
+void PMDataManager::emitIRSizeChangedRemark(Pass *P, Module &M,
+ const int &OriginalCount,
+ const int &FinalCount) {
+ // If there was no change, don't emit a remark.
+ if (OriginalCount == FinalCount)
+ return;
+
+ // If it's a pass manager, don't emit a remark. (This hinges on the assumption
+ // that the only passes that return non-null with getAsPMDataManager are
+ // pass managers.)
+ if (P->getAsPMDataManager())
+ return;
+
+ Function &F = *M.begin();
+ BasicBlock &BB = *F.begin();
+ OptimizationRemarkAnalysis R("size-info", "IRSizeChange",
+ DiagnosticLocation(), &BB);
+ R << DiagnosticInfoOptimizationBase::Argument("Pass", P->getPassName())
+ << ": IR instruction count changed from "
+ << DiagnosticInfoOptimizationBase::Argument("IRInstrsBefore", OriginalCount)
+ << " to "
+ << DiagnosticInfoOptimizationBase::Argument("IRInstrsAfter", FinalCount)
+ << "; Delta: "
+ << DiagnosticInfoOptimizationBase::Argument("DeltaInstrCount",
+ FinalCount - OriginalCount);
+ F.getContext().diagnose(R);
+}
void PassManagerPrettyStackEntry::print(raw_ostream &OS) const {
if (!V && !M)
@@ -173,7 +199,7 @@
public:
static char ID;
- explicit BBPassManager()
+ explicit BBPassManager()
: PMDataManager(), FunctionPass(ID) {}
/// Execute all of the passes scheduled for execution. Keep track of
@@ -322,7 +348,7 @@
using llvm::Pass::doInitialization;
using llvm::Pass::doFinalization;
-
+
/// Pass Manager itself does not invalidate any analysis info.
void getAnalysisUsage(AnalysisUsage &Info) const override {
Info.setPreservesAll();
@@ -350,7 +376,7 @@
ModulePass *MP = getContainedPass(Index);
MP->dumpPassStructure(Offset + 1);
std::map<Pass *, FunctionPassManagerImpl *>::const_iterator I =
- OnTheFlyManagers.find(MP);
+ OnTheFlyManagers.find(MP);
if (I != OnTheFlyManagers.end())
I->second->dumpPassStructure(Offset + 2);
dumpLastUses(MP, Offset+1);
@@ -366,7 +392,7 @@
return PMT_ModulePassManager;
}
- private:
+private:
/// Collection of on the fly FPPassManagers. These managers manage
/// function passes that are required by module passes.
std::map<Pass *, FunctionPassManagerImpl *> OnTheFlyManagers;
@@ -394,8 +420,8 @@
PMTopLevelManager(new MPPassManager()) {}
/// \copydoc PassManager::add()
- void add(Pass *P) {
- schedulePass(P);
+ void add(Pass *P) {
+ schedulePass(P);
}
/// createPrinterPass - Get a module printer pass.
@@ -410,7 +436,7 @@
using llvm::Pass::doInitialization;
using llvm::Pass::doFinalization;
-
+
/// Pass Manager itself does not invalidate any analysis info.
void getAnalysisUsage(AnalysisUsage &Info) const override {
Info.setPreservesAll();
@@ -467,8 +493,8 @@
static void createTheTimeInfo();
// print - Prints out timing information and then resets the timers.
- void print() {
- TG.print(*CreateInfoOutputFile());
+ void print() {
+ TG.print(*CreateInfoOutputFile());
}
/// getPassTimer - Return the timer for the specified pass if it exists.
@@ -554,7 +580,7 @@
void PMTopLevelManager::collectLastUses(SmallVectorImpl<Pass *> &LastUses,
Pass *P) {
DenseMap<Pass *, SmallPtrSet<Pass *, 8> >::iterator DMI =
- InversedLastUser.find(P);
+ InversedLastUser.find(P);
if (DMI == InversedLastUser.end())
return;
@@ -579,7 +605,7 @@
// of dependencies.
AnalysisUsage AU;
P->getAnalysisUsage(AU);
-
+
AUFoldingSetNode* Node = nullptr;
FoldingSetNodeID ID;
AUFoldingSetNode::Profile(ID, AU);
@@ -873,7 +899,7 @@
const AnalysisUsage::VectorType &PreservedSet = AnUsage->getPreservedSet();
for (DenseMap<AnalysisID, Pass*>::iterator I = AvailableAnalysis.begin(),
- E = AvailableAnalysis.end(); I != E; ) {
+ E = AvailableAnalysis.end(); I != E; ) {
DenseMap<AnalysisID, Pass*>::iterator Info = I++;
if (Info->second->getAsImmutablePass() == nullptr &&
!is_contained(PreservedSet, Info->first)) {
@@ -895,8 +921,8 @@
continue;
for (DenseMap<AnalysisID, Pass*>::iterator
- I = InheritedAnalysis[Index]->begin(),
- E = InheritedAnalysis[Index]->end(); I != E; ) {
+ I = InheritedAnalysis[Index]->begin(),
+ E = InheritedAnalysis[Index]->end(); I != E; ) {
DenseMap<AnalysisID, Pass *>::iterator Info = I++;
if (Info->second->getAsImmutablePass() == nullptr &&
!is_contained(PreservedSet, Info->first)) {
@@ -956,7 +982,7 @@
const std::vector<const PassInfo*> &II = PInf->getInterfacesImplemented();
for (unsigned i = 0, e = II.size(); i != e; ++i) {
DenseMap<AnalysisID, Pass*>::iterator Pos =
- AvailableAnalysis.find(II[i]->getTypeInfo());
+ AvailableAnalysis.find(II[i]->getTypeInfo());
if (Pos != AvailableAnalysis.end() && Pos->second == P)
AvailableAnalysis.erase(Pos);
}
@@ -1120,16 +1146,16 @@
for (Pass *P : PassVector) {
if (PMDataManager *PMD = P->getAsPMDataManager())
PMD->dumpPassArguments();
- else
- if (const PassInfo *PI =
+ else
+ if (const PassInfo *PI =
TPM->findAnalysisPassInfo(P->getPassID()))
- if (!PI->isAnalysisGroup())
- dbgs() << " -" << PI->getPassArgument();
+ if (!PI->isAnalysisGroup())
+ dbgs() << " -" << PI->getPassArgument();
}
}
void PMDataManager::dumpPassInfo(Pass *P, enum PassDebuggingString S1,
- enum PassDebuggingString S2,
+ enum PassDebuggingString S2,
StringRef Msg) {
if (PassDebugging < Executions)
return;
@@ -1278,6 +1304,8 @@
return false;
bool Changed = doInitialization(F);
+ Module &M = *F.getParent();
+ int ModuleCount = M.getModuleInstrCount();
for (BasicBlock &BB : F)
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
@@ -1294,7 +1322,17 @@
PassManagerPrettyStackEntry X(BP, BB);
TimeRegion PassTimer(getPassTimer(BP));
- LocalChanged |= BP->runOnBasicBlock(BB);
+ int OrigBBCount = BB.size();
+
+ // Run BP on BB and check if anything changed.
+ if (BP->runOnBasicBlock(BB)) {
+ // It changed something. Keep track of the local change, and emit a
+ // remark if it changed the size of the module.
+ LocalChanged = true;
+ int InstrDiff = BB.size() - OrigBBCount;
+ emitIRSizeChangedRemark(BP, M, ModuleCount, ModuleCount + InstrDiff);
+ ModuleCount += InstrDiff;
+ }
}
Changed |= LocalChanged;
@@ -1368,12 +1406,12 @@
FPM->setResolver(AR);
}
-FunctionPassManager::~FunctionPassManager() {
- delete FPM;
+FunctionPassManager::~FunctionPassManager() {
+ delete FPM;
}
-void FunctionPassManager::add(Pass *P) {
- FPM->add(P);
+void FunctionPassManager::add(Pass *P) {
+ FPM->add(P);
}
/// run - Execute all of the passes scheduled for execution. Keep
@@ -1396,8 +1434,8 @@
/// doFinalization - Run all of the finalizers for the function passes.
///
-bool FunctionPassManager::doFinalization() {
- return FPM->doFinalization(*M);
+bool FunctionPassManager::doFinalization() {
+ return FPM->doFinalization(*M);
}
//===----------------------------------------------------------------------===//
@@ -1432,12 +1470,12 @@
/// cleanup - After running all passes, clean up pass manager cache.
void FPPassManager::cleanup() {
- for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
+ for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
FunctionPass *FP = getContainedPass(Index);
AnalysisResolver *AR = FP->getResolver();
assert(AR && "Analysis Resolver is not set");
AR->clearAnalysisImpls();
- }
+ }
}
void FunctionPassManagerImpl::releaseMemoryOnTheFly() {
@@ -1494,6 +1532,8 @@
return false;
bool Changed = false;
+ Module &M = *(F.getParent());
+ int ModuleCount = M.getModuleInstrCount();
// Collect inherited analysis from Module level pass manager.
populateInheritedAnalysis(TPM->activeStack);
@@ -1511,7 +1551,17 @@
PassManagerPrettyStackEntry X(FP, F);
TimeRegion PassTimer(getPassTimer(FP));
- LocalChanged |= FP->runOnFunction(F);
+ int OrigFnCount = F.getFunctionInstrCount();
+
+ // Did FP modify F?
+ if (FP->runOnFunction(F)) {
+ // It changed something. Keep track of the local change, and emit a
+ // remark if it changed the size of the module.
+ LocalChanged = true;
+ int InstrDiff = F.getFunctionInstrCount() - OrigFnCount;
+ emitIRSizeChangedRemark(FP, M, ModuleCount, ModuleCount + InstrDiff);
+ ModuleCount += InstrDiff;
+ }
}
Changed |= LocalChanged;
@@ -1588,11 +1638,15 @@
PassManagerPrettyStackEntry X(MP, M);
TimeRegion PassTimer(getPassTimer(MP));
+ int OriginalCount = M.getModuleInstrCount();
LocalChanged |= MP->runOnModule(M);
+
+ // If MP changed the size of the module, then emit a remark.
+ emitIRSizeChangedRemark(MP, M, OriginalCount, M.getModuleInstrCount());
}
Changed |= LocalChanged;
- if (LocalChanged)
+ if (LocalChanged)
dumpPassInfo(MP, MODIFICATION_MSG, ON_MODULE_MSG,
M.getModuleIdentifier());
dumpPreservedSet(MP);
@@ -1646,7 +1700,7 @@
Pass *FoundPass = nullptr;
if (RequiredPassPI && RequiredPassPI->isAnalysis()) {
FoundPass =
- ((PMTopLevelManager*)FPP)->findAnalysisPass(RequiredPass->getPassID());
+ ((PMTopLevelManager*)FPP)->findAnalysisPass(RequiredPass->getPassID());
}
if (!FoundPass) {
FoundPass = RequiredPass;
@@ -1902,4 +1956,4 @@
BBP->add(this);
}
-PassManagerBase::~PassManagerBase() {}
+PassManagerBase::~PassManagerBase() {}
\ No newline at end of file
Index: lib/IR/Module.cpp
===================================================================
--- lib/IR/Module.cpp
+++ lib/IR/Module.cpp
@@ -323,6 +323,13 @@
return getOrInsertNamedMetadata("llvm.module.flags");
}
+int Module::getModuleInstrCount() {
+ int IRCount = 0;
+ for (Function &F : FunctionList)
+ IRCount += F.getFunctionInstrCount();
+ return IRCount;
+}
+
/// addModuleFlag - Add a module-level flag to the module-level flags
/// metadata. It will create the module-level flags named metadata if it doesn't
/// already exist.
Index: test/Other/size-remarks.ll
===================================================================
--- /dev/null
+++ test/Other/size-remarks.ll
@@ -0,0 +1,159 @@
+; Ensure that IR count remarks in the pass manager work for every type of
+; pass that we handle.
+
+; First, make sure remarks work for CGSCC passes.
+; RUN: opt < %s -inline -pass-remarks-analysis='size-info' -S 2>&1 \
+; RUN: | FileCheck %s -check-prefix=CGSCC
+; CGSCC: remark: <unknown>:0:0: Function Integration/Inlining:
+; CGSCC-SAME: IR instruction count changed from 17 to 31; Delta: 14
+; RUN: opt < %s -inline -pass-remarks-analysis='size-info' -S \
+; RUN: -pass-remarks-output=%t.cgscc.yaml -o /dev/null
+; RUN: cat %t.cgscc.yaml | FileCheck %s -check-prefix=CGSCC-YAML
+; CGSCC-YAML: --- !Analysis
+; CGSCC-YAML-NEXT: Pass: size-info
+; CGSCC-YAML-NEXT: Name: IRSizeChange
+; CGSCC-YAML-NEXT: Function: baz
+; CGSCC-YAML-NEXT: Args:
+; CGSCC-YAML-NEXT: - Pass: Function Integration/Inlining
+; CGSCC-YAML-NEXT: - String: ': IR instruction count changed from '
+; CGSCC-YAML-NEXT: - IRInstrsBefore: '17'
+; CGSCC-YAML-NEXT: - String: ' to '
+; CGSCC-YAML-NEXT: - IRInstrsAfter: '31'
+; CGSCC-YAML-NEXT: - String: '; Delta: '
+; CGSCC-YAML-NEXT: - DeltaInstrCount: '14'
+
+; Next, make sure it works for function passes.
+; RUN: opt < %s -instcombine -pass-remarks-analysis='size-info' -S 2>&1 \
+; RUN: | FileCheck %s -check-prefix=FUNC
+; FUNC: remark: <unknown>:0:0: Combine redundant instructions:
+; FUNC-SAME: IR instruction count changed from 17 to 16; Delta: -1
+; FUNC: remark: <unknown>:0:0: Combine redundant instructions:
+; FUNC-SAME: IR instruction count changed from 16 to 10; Delta: -6
+; FUNC: remark: <unknown>:0:0: Combine redundant instructions:
+; FUNC-SAME: IR instruction count changed from 10 to 6; Delta: -4
+; RUN: opt < %s -instcombine -pass-remarks-analysis='size-info' -S \
+; RUN: -pass-remarks-output=%t.func.yaml -o /dev/null
+; RUN: cat %t.func.yaml | FileCheck %s -check-prefix=FUNC-YAML
+
+; FUNC-YAML: --- !Analysis
+; FUNC-YAML-NEXT: Pass: size-info
+; FUNC-YAML-NEXT: Name: IRSizeChange
+; FUNC-YAML-NEXT: Function: baz
+; FUNC-YAML-NEXT: Args:
+; FUNC-YAML-NEXT: - Pass: Combine redundant instructions
+; FUNC-YAML-NEXT: - String: ': IR instruction count changed from '
+; FUNC-YAML-NEXT: - IRInstrsBefore: '17'
+; FUNC-YAML-NEXT: - String: ' to '
+; FUNC-YAML-NEXT: - IRInstrsAfter: '16'
+; FUNC-YAML-NEXT: - String: '; Delta: '
+; FUNC-YAML-NEXT: - DeltaInstrCount: '-1'
+
+; FUNC-YAML: --- !Analysis
+; FUNC-YAML-NEXT: Pass: size-info
+; FUNC-YAML-NEXT: Name: IRSizeChange
+; FUNC-YAML-NEXT: Function: baz
+; FUNC-YAML-NEXT: Args:
+; FUNC-YAML-NEXT: - Pass: Combine redundant instructions
+; FUNC-YAML-NEXT: - String: ': IR instruction count changed from '
+; FUNC-YAML-NEXT: - IRInstrsBefore: '16'
+; FUNC-YAML-NEXT: - String: ' to '
+; FUNC-YAML-NEXT: - IRInstrsAfter: '10'
+; FUNC-YAML-NEXT: - String: '; Delta: '
+; FUNC-YAML-NEXT: - DeltaInstrCount: '-6'
+
+; FUNC-YAML: --- !Analysis
+; FUNC-YAML-NEXT: Pass: size-info
+; FUNC-YAML-NEXT: Name: IRSizeChange
+; FUNC-YAML-NEXT: Function: baz
+; FUNC-YAML-NEXT: Args:
+; FUNC-YAML-NEXT: - Pass: Combine redundant instructions
+; FUNC-YAML-NEXT: - String: ': IR instruction count changed from '
+; FUNC-YAML-NEXT: - IRInstrsBefore: '10'
+; FUNC-YAML-NEXT: - String: ' to '
+; FUNC-YAML-NEXT: - IRInstrsAfter: '6'
+; FUNC-YAML-NEXT: - String: '; Delta: '
+; FUNC-YAML-NEXT: - DeltaInstrCount: '-4'
+
+; Make sure it works for module passes.
+; RUN: opt < %s -gvn -pass-remarks-analysis='size-info' -S 2>&1 \
+; RUN: | FileCheck %s -check-prefix=MODULE
+; MODULE: remark: <unknown>:0:0: Global Value Numbering:
+; MODULE-SAME: IR instruction count changed from 17 to 15; Delta: -2
+; MODULE: remark: <unknown>:0:0: Global Value Numbering:
+; MODULE-SAME: IR instruction count changed from 15 to 13; Delta: -2
+; RUN: opt < %s -gvn -pass-remarks-analysis='size-info' -S \
+; RUN: -pass-remarks-output=%t.module.yaml -o /dev/null
+; RUN: cat %t.module.yaml | FileCheck %s -check-prefix=MODULE-YAML
+; MODULE-YAML: --- !Analysis
+; MODULE-YAML-NEXT: Pass: size-info
+; MODULE-YAML-NEXT: Name: IRSizeChange
+; MODULE-YAML-NEXT: Function: baz
+; MODULE-YAML-NEXT: Args:
+; MODULE-YAML-NEXT: - Pass: Global Value Numbering
+; MODULE-YAML-NEXT: - String: ': IR instruction count changed from '
+; MODULE-YAML-NEXT: - IRInstrsBefore: '17'
+; MODULE-YAML-NEXT: - String: ' to '
+; MODULE-YAML-NEXT: - IRInstrsAfter: '15'
+; MODULE-YAML-NEXT: - String: '; Delta: '
+; MODULE-YAML-NEXT: - DeltaInstrCount: '-2'
+; MODULE-YAML: --- !Analysis
+; MODULE-YAML-NEXT: Pass: size-info
+; MODULE-YAML-NEXT: Name: IRSizeChange
+; MODULE-YAML-NEXT: Function: baz
+; MODULE-YAML-NEXT: Args:
+; MODULE-YAML-NEXT: - Pass: Global Value Numbering
+; MODULE-YAML-NEXT: - String: ': IR instruction count changed from '
+; MODULE-YAML-NEXT: - IRInstrsBefore: '15'
+; MODULE-YAML-NEXT: - String: ' to '
+; MODULE-YAML-NEXT: - IRInstrsAfter: '13'
+; MODULE-YAML-NEXT: - String: '; Delta: '
+; MODULE-YAML-NEXT: - DeltaInstrCount: '-2'
+
+; Make sure it works for basic block passes.
+; RUN: opt < %s -dce -pass-remarks-analysis='size-info' -S 2>&1 \
+; RUN: | FileCheck %s -check-prefix=BB
+; BB: remark: <unknown>:0:0: Dead Code Elimination:
+; BB-SAME: IR instruction count changed from 17 to 16; Delta: -1
+; RUN: opt < %s -dce -pass-remarks-analysis='size-info' -S \
+; RUN: -pass-remarks-output=%t.bb.yaml -o /dev/null
+; RUN: cat %t.bb.yaml | FileCheck %s -check-prefix=BB-YAML
+; BB-YAML: --- !Analysis
+; BB-YAML-NEXT: Pass: size-info
+; BB-YAML-NEXT: Name: IRSizeChange
+; BB-YAML-NEXT: Function: baz
+; BB-YAML-NEXT: Args:
+; BB-YAML-NEXT: - Pass: Dead Code Elimination
+; BB-YAML-NEXT: - String: ': IR instruction count changed from '
+; BB-YAML-NEXT: - IRInstrsBefore: '17'
+; BB-YAML-NEXT: - String: ' to '
+; BB-YAML-NEXT: - IRInstrsAfter: '16'
+; BB-YAML-NEXT: - String: '; Delta: '
+; BB-YAML-NEXT: - DeltaInstrCount: '-1'
+
+define void @baz() #0 {
+ %x.addr = alloca i32, align 4
+ ret void
+}
+
+define i32 @foo(i32 %x, i32 %y) #0 {
+entry:
+ %x.addr = alloca i32, align 4
+ %y.addr = alloca i32, align 4
+ store i32 %x, i32* %x.addr, align 4
+ store i32 %y, i32* %y.addr, align 4
+ %0 = load i32, i32* %x.addr, align 4
+ %1 = load i32, i32* %y.addr, align 4
+ %add = add nsw i32 %0, %1
+ ret i32 %add
+}
+
+define i32 @bar(i32 %j) #0 {
+entry:
+ %j.addr = alloca i32, align 4
+ store i32 %j, i32* %j.addr, align 4
+ %0 = load i32, i32* %j.addr, align 4
+ %1 = load i32, i32* %j.addr, align 4
+ %sub = sub nsw i32 %1, 2
+ %call = call i32 @foo(i32 %0, i32 %sub)
+ ret i32 %call
+}
\ No newline at end of file