Changed stat passes to count instructions before and after optimizations (#188837)

Created this for instcount and func-properties-analysis to be able to see the change the optimization pipelines have on stats
2026-04-10 19:47:52 -06:00
parent afce975a24
commit ea8554e35b
11 changed files with 222 additions and 36 deletions
--- a/llvm/include/llvm/Analysis/FunctionPropertiesAnalysis.h
+++ b/llvm/include/llvm/Analysis/FunctionPropertiesAnalysis.h
@@ -185,8 +185,14 @@ public:
 };

 /// Statistics pass for the FunctionPropertiesAnalysis results.
-struct FunctionPropertiesStatisticsPass
-    : PassInfoMixin<FunctionPropertiesStatisticsPass> {
+class FunctionPropertiesStatisticsPass
+    : public PassInfoMixin<FunctionPropertiesStatisticsPass> {
+  bool IsPreOptimization;
+
+public:
+  explicit FunctionPropertiesStatisticsPass(bool IsPreOptimization = false)
+      : IsPreOptimization(IsPreOptimization) {}
+
  PreservedAnalyses run(Function &F, FunctionAnalysisManager &FAM);
 };

--- a/llvm/include/llvm/Analysis/InstCount.h
+++ b/llvm/include/llvm/Analysis/InstCount.h
@@ -19,8 +19,14 @@ namespace llvm {

 class Function;

-struct InstCountPass : PassInfoMixin<InstCountPass> {
-  PreservedAnalyses run(Function &F, FunctionAnalysisManager &);
+class InstCountPass : public PassInfoMixin<InstCountPass> {
+  bool IsPreOptimization;
+
+public:
+  explicit InstCountPass(bool IsPreOptimization = false)
+      : IsPreOptimization(IsPreOptimization) {}
+
+  PreservedAnalyses run(Function &F, FunctionAnalysisManager &FAM);
 };

 } // end namespace llvm
--- a/llvm/lib/Analysis/FunctionPropertiesAnalysis.cpp
+++ b/llvm/lib/Analysis/FunctionPropertiesAnalysis.cpp
@@ -29,8 +29,13 @@ using namespace llvm;

 #define DEBUG_TYPE "func-properties-stats"

-#define FUNCTION_PROPERTY(Name, Description) STATISTIC(Num##Name, Description);
+#define FUNCTION_PROPERTY(Name, Description)                                   \
+  STATISTIC(Num##Name##PreOptimization,                                        \
+            Description " (before optimizations)");                            \
+  STATISTIC(Num##Name, Description);
 #define DETAILED_FUNCTION_PROPERTY(Name, Description)                          \
+  STATISTIC(Num##Name##PreOptimization,                                        \
+            Description " (before optimizations)");                            \
  STATISTIC(Num##Name, Description);
 #include "llvm/IR/FunctionProperties.def"

@@ -378,11 +383,22 @@ FunctionPropertiesStatisticsPass::run(Function &F,
  LLVM_DEBUG(dbgs() << "STATSCOUNT: running on function " << F.getName()
                    << "\n");
  auto &AnalysisResults = FAM.getResult<FunctionPropertiesAnalysis>(F);
-
+  if (IsPreOptimization) {
+#define FUNCTION_PROPERTY(Name, Description)                                   \
+  Num##Name##PreOptimization += AnalysisResults.Name;
+#define DETAILED_FUNCTION_PROPERTY(Name, Description)                          \
+  Num##Name##PreOptimization += AnalysisResults.Name;
+#include "llvm/IR/FunctionProperties.def"
+#undef FUNCTION_PROPERTY
+#undef DETAILED_FUNCTION_PROPERTY
+  } else {
 #define FUNCTION_PROPERTY(Name, Description) Num##Name += AnalysisResults.Name;
 #define DETAILED_FUNCTION_PROPERTY(Name, Description)                          \
  Num##Name += AnalysisResults.Name;
 #include "llvm/IR/FunctionProperties.def"
+#undef FUNCTION_PROPERTY
+#undef DETAILED_FUNCTION_PROPERTY
+  }

  return PreservedAnalyses::all();
 }
--- a/llvm/lib/Analysis/InstCount.cpp
+++ b/llvm/lib/Analysis/InstCount.cpp
@@ -21,15 +21,29 @@ using namespace llvm;

 #define DEBUG_TYPE "instcount"

-STATISTIC(TotalInsts, "Number of instructions (of all types)");
+STATISTIC(TotalInstsPreOptimization,
+          "Number of instructions of all types (before optimizations)");
+STATISTIC(TotalInsts, "Number of instructions of all types");
+STATISTIC(TotalBlocksPreOptimization,
+          "Number of basic blocks (before optimizations)");
 STATISTIC(TotalBlocks, "Number of basic blocks");
+STATISTIC(TotalFuncsPreOptimization,
+          "Number of non-external functions (before optimizations)");
 STATISTIC(TotalFuncs, "Number of non-external functions");
+STATISTIC(LargestFunctionSizePreOptimization,
+          "Largest number of instructions in a single function (before "
+          "optimizations)");
 STATISTIC(LargestFunctionSize,
          "Largest number of instructions in a single function");
+STATISTIC(LargestFunctionBBCountPreOptimization,
+          "Largest number of basic blocks in a single function (before "
+          "optimizations)");
 STATISTIC(LargestFunctionBBCount,
          "Largest number of basic blocks in a single function");

 #define HANDLE_INST(N, OPCODE, CLASS)                                          \
+  STATISTIC(Num##OPCODE##InstPreOptimization,                                  \
+            "Number of " #OPCODE " insts (before optimizations)");             \
  STATISTIC(Num##OPCODE##Inst, "Number of " #OPCODE " insts");

 #include "llvm/IR/Instruction.def"
@@ -37,18 +51,39 @@ STATISTIC(LargestFunctionBBCount,
 namespace {
 class InstCount : public InstVisitor<InstCount> {
  friend class InstVisitor<InstCount>;
+  bool IsPreOptimization;
+
+public:
+  InstCount(bool IsPreOptimization) : IsPreOptimization(IsPreOptimization) {}

  void visitFunction(Function &F) {
-    ++TotalFuncs;
-    LargestFunctionSize.updateMax(F.getInstructionCount());
-    LargestFunctionBBCount.updateMax(F.size());
+    if (IsPreOptimization) {
+      ++TotalFuncsPreOptimization;
+      LargestFunctionSizePreOptimization.updateMax(F.getInstructionCount());
+      LargestFunctionBBCountPreOptimization.updateMax(F.size());
+    } else {
+      ++TotalFuncs;
+      LargestFunctionSize.updateMax(F.getInstructionCount());
+      LargestFunctionBBCount.updateMax(F.size());
+    }
+  }
+
+  void visitBasicBlock(BasicBlock &BB) {
+    if (IsPreOptimization)
+      ++TotalBlocksPreOptimization;
+    else
+      ++TotalBlocks;
  }
-  void visitBasicBlock(BasicBlock &BB) { ++TotalBlocks; }

 #define HANDLE_INST(N, OPCODE, CLASS)                                          \
  void visit##OPCODE(CLASS &) {                                                \
-    ++Num##OPCODE##Inst;                                                       \
-    ++TotalInsts;                                                              \
+    if (IsPreOptimization) {                                                   \
+      ++Num##OPCODE##InstPreOptimization;                                      \
+      ++TotalInstsPreOptimization;                                             \
+    } else {                                                                   \
+      ++Num##OPCODE##Inst;                                                     \
+      ++TotalInsts;                                                            \
+    }                                                                          \
  }

 #include "llvm/IR/Instruction.def"
@@ -64,7 +99,7 @@ PreservedAnalyses InstCountPass::run(Function &F,
                                     FunctionAnalysisManager &FAM) {
  LLVM_DEBUG(dbgs() << "INSTCOUNT: running on function " << F.getName()
                    << "\n");
-  InstCount().visit(F);
+  InstCount(this->IsPreOptimization).visit(F);

  return PreservedAnalyses::all();
 }
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -806,6 +806,17 @@ Expected<bool> parseLintOptions(StringRef Params) {
                                            "LintPass");
 }

+/// Parser of parameters for FunctionPropertiesStatistics pass.
+Expected<bool> parseFunctionPropertiesStatisticsOptions(StringRef Params) {
+  return PassBuilder::parseSinglePassOption(Params, "pre-opt",
+                                            "FunctionPropertiesStatisticsPass");
+}
+
+/// Parser of parameters for InstCount pass.
+Expected<bool> parseInstCountOptions(StringRef Params) {
+  return PassBuilder::parseSinglePassOption(Params, "pre-opt", "InstCountPass");
+}
+
 /// Parser of parameters for LoopUnroll pass.
 Expected<LoopUnrollOptions> parseLoopUnrollOptions(StringRef Params) {
  LoopUnrollOptions UnrollOpts;
--- a/llvm/lib/Passes/PassBuilderPipelines.cpp
+++ b/llvm/lib/Passes/PassBuilderPipelines.cpp
@@ -413,15 +413,19 @@ void PassBuilder::invokePipelineEarlySimplificationEPCallbacks(
    C(MPM, Level, Phase);
 }

+// Get IR stats with InstCount and FunctionPropertiesAnalysis.
+static void instructionCountersPass(ModulePassManager &MPM,
+                                    bool IsPreOptimization) {
+  if (AreStatisticsEnabled()) {
+    MPM.addPass(
+        createModuleToFunctionPassAdaptor(InstCountPass(IsPreOptimization)));
+    MPM.addPass(createModuleToFunctionPassAdaptor(
+        FunctionPropertiesStatisticsPass(IsPreOptimization)));
+  }
+}
 // Helper to add AnnotationRemarksPass.
 static void addAnnotationRemarksPass(ModulePassManager &MPM) {
  MPM.addPass(createModuleToFunctionPassAdaptor(AnnotationRemarksPass()));
-  // Count the stats for InstCount and FunctionPropertiesAnalysis
-  if (AreStatisticsEnabled()) {
-    MPM.addPass(createModuleToFunctionPassAdaptor(InstCountPass()));
-    MPM.addPass(
-        createModuleToFunctionPassAdaptor(FunctionPropertiesStatisticsPass()));
-  }
 }

 // Helper to check if the current compilation phase is preparing for LTO
@@ -1712,6 +1716,7 @@ PassBuilder::buildPerModuleDefaultPipeline(OptimizationLevel Level,
    return buildO0DefaultPipeline(Level, Phase);

  ModulePassManager MPM;
+  instructionCountersPass(MPM, /*IsPreOptimization=*/true);

  // Currently this pipeline is only invoked in an LTO pre link pass or when we
  // are not running LTO. If that changes the below checks may need updating.
@@ -1750,6 +1755,9 @@ PassBuilder::buildPerModuleDefaultPipeline(OptimizationLevel Level,

  if (isLTOPreLink(Phase))
    addRequiredLTOPreLinkPasses(MPM);
+
+  instructionCountersPass(MPM, /*IsPreOptimization=*/false);
+
  return MPM;
 }

@@ -1757,6 +1765,9 @@ ModulePassManager
 PassBuilder::buildFatLTODefaultPipeline(OptimizationLevel Level, bool ThinLTO,
                                        bool EmitSummary) {
  ModulePassManager MPM;
+
+  instructionCountersPass(MPM, /*IsPreOptimization=*/true);
+
  if (ThinLTO)
    MPM.addPass(buildThinLTOPreLinkDefaultPipeline(Level));
  else
@@ -1799,6 +1810,9 @@ PassBuilder::buildFatLTODefaultPipeline(OptimizationLevel Level, bool ThinLTO,
    // Emit annotation remarks.
    addAnnotationRemarksPass(MPM);
  }
+
+  instructionCountersPass(MPM, /*IsPreOptimization=*/false);
+
  return MPM;
 }

@@ -1809,6 +1823,8 @@ PassBuilder::buildThinLTOPreLinkDefaultPipeline(OptimizationLevel Level) {

  ModulePassManager MPM;

+  instructionCountersPass(MPM, /*IsPreOptimization=*/true);
+
  // Convert @llvm.global.annotations to !annotation metadata.
  MPM.addPass(Annotation2MetadataPass());

@@ -1861,6 +1877,8 @@ PassBuilder::buildThinLTOPreLinkDefaultPipeline(OptimizationLevel Level) {

  addRequiredLTOPreLinkPasses(MPM);

+  instructionCountersPass(MPM, /*IsPreOptimization=*/false);
+
  return MPM;
 }

@@ -1868,6 +1886,8 @@ ModulePassManager PassBuilder::buildThinLTODefaultPipeline(
    OptimizationLevel Level, const ModuleSummaryIndex *ImportSummary) {
  ModulePassManager MPM;

+  instructionCountersPass(MPM, /*IsPreOptimization=*/true);
+
  // If we are invoking this without a summary index noting that we are linking
  // with a library containing the necessary APIs, remove any MemProf related
  // attributes and metadata.
@@ -1916,6 +1936,8 @@ ModulePassManager PassBuilder::buildThinLTODefaultPipeline(
    // globals in the object file.
    MPM.addPass(EliminateAvailableExternallyPass());
    MPM.addPass(GlobalDCEPass());
+
+    instructionCountersPass(MPM, /*IsPreOptimization=*/false);
    return MPM;
  }
  if (!UseCtxProfile.empty()) {
@@ -1933,6 +1955,8 @@ ModulePassManager PassBuilder::buildThinLTODefaultPipeline(
  // Emit annotation remarks.
  addAnnotationRemarksPass(MPM);

+  instructionCountersPass(MPM, /*IsPreOptimization=*/false);
+
  return MPM;
 }

@@ -1948,6 +1972,8 @@ PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level,
                                     ModuleSummaryIndex *ExportSummary) {
  ModulePassManager MPM;

+  instructionCountersPass(MPM, /*IsPreOptimization=*/true);
+
  invokeFullLinkTimeOptimizationEarlyEPCallbacks(MPM, Level);

  // If we are invoking this without a summary index noting that we are linking
@@ -2308,6 +2334,8 @@ PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level,
  // Emit annotation remarks.
  addAnnotationRemarksPass(MPM);

+  instructionCountersPass(MPM, /*IsPreOptimization=*/false);
+
  return MPM;
 }

@@ -2319,6 +2347,8 @@ PassBuilder::buildO0DefaultPipeline(OptimizationLevel Level,

  ModulePassManager MPM;

+  instructionCountersPass(MPM, /*IsPreOptimization=*/true);
+
  // Perform pseudo probe instrumentation in O0 mode. This is for the
  // consistency between different build modes. For example, a LTO build can be
  // mixed with an O0 prelink and an O2 postlink. Loading a sample profile in
@@ -2432,6 +2462,8 @@ PassBuilder::buildO0DefaultPipeline(OptimizationLevel Level,
  // Emit annotation remarks.
  addAnnotationRemarksPass(MPM);

+  instructionCountersPass(MPM, /*IsPreOptimization=*/false);
+
  return MPM;
 }

--- a/llvm/lib/Passes/PassRegistry.def
+++ b/llvm/lib/Passes/PassRegistry.def
@@ -440,7 +440,6 @@ FUNCTION_PASS("fix-irreducible", FixIrreduciblePass())
 FUNCTION_PASS("flatten-cfg", FlattenCFGPass())
 FUNCTION_PASS("float2int", Float2IntPass())
 FUNCTION_PASS("free-machine-function", FreeMachineFunctionPass())
-FUNCTION_PASS("func-properties-stats", FunctionPropertiesStatisticsPass())
 FUNCTION_PASS("gc-lowering", GCLoweringPass())
 FUNCTION_PASS("guard-widening", GuardWideningPass())
 FUNCTION_PASS("gvn-hoist", GVNHoistPass())
@@ -451,7 +450,6 @@ FUNCTION_PASS("infer-address-spaces", InferAddressSpacesPass())
 FUNCTION_PASS("infer-alignment", InferAlignmentPass())
 FUNCTION_PASS("inject-tli-mappings", InjectTLIMappings())
 FUNCTION_PASS("inline-asm-prepare", InlineAsmPreparePass())
-FUNCTION_PASS("instcount", InstCountPass())
 FUNCTION_PASS("instnamer", InstructionNamerPass())
 FUNCTION_PASS("instsimplify", InstSimplifyPass())
 FUNCTION_PASS("interleaved-access", InterleavedAccessPass(*TM))
@@ -589,6 +587,13 @@ FUNCTION_PASS_WITH_PARAMS(
    "ee-instrument", "EntryExitInstrumenterPass",
    [](bool PostInlining) { return EntryExitInstrumenterPass(PostInlining); },
    parseEntryExitInstrumenterPassOptions, "post-inline")
+FUNCTION_PASS_WITH_PARAMS(
+    "func-properties-stats", 
+    "FunctionPropertiesStatisticsPass",
+    [](bool IsPreOptimizations) { 
+      return FunctionPropertiesStatisticsPass(IsPreOptimizations); 
+    },
+    parseFunctionPropertiesStatisticsOptions, "pre-opt")
 FUNCTION_PASS_WITH_PARAMS(
    "function-simplification", "",
    [this](OptimizationLevel OL) {
@@ -612,6 +617,12 @@ FUNCTION_PASS_WITH_PARAMS(
    [](InstCombineOptions Opts) { return InstCombinePass(Opts); },
    parseInstCombineOptions,
    "no-verify-fixpoint;verify-fixpoint;max-iterations=N")
+FUNCTION_PASS_WITH_PARAMS(
+    "instcount", "InstCountPass",
+    [](bool IsPreOptimizations) { 
+      return InstCountPass(IsPreOptimizations); 
+    },
+    parseInstCountOptions, "pre-opt")
 FUNCTION_PASS_WITH_PARAMS(
    "lint", "LintPass",
    [](bool AbortOnError) { return LintPass(AbortOnError); }, parseLintOptions,
--- a/llvm/test/Analysis/FunctionPropertiesAnalysis/function-properties-analysis.ll
+++ b/llvm/test/Analysis/FunctionPropertiesAnalysis/function-properties-analysis.ll
@@ -1,11 +1,5 @@
-; Testing with all of the below run lines that the pass gets added to the appropriate pipelines
 ; REQUIRES: asserts
 ; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes=func-properties-stats < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='thinlto<O3>' < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='thinlto-pre-link<O2>' < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='lto<O1>' < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -enable-detailed-function-properties -disable-output -O3 < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -enable-detailed-function-properties -disable-output -O0 < %s 2>&1 | FileCheck %s

 ; CHECK-DAG: 10 func-properties-stats - Number of basic blocks
 ; CHECK-DAG: 8 func-properties-stats - Number of branch instructions
@@ -17,7 +11,6 @@
 ; CHECK-DAG: 1 func-properties-stats - Number of switch instructions
 ; CHECK-DAG: 4 func-properties-stats - Number of switch successors

-
 define void @foo(i32 %i, i32 %j, i32 %n) {
 entry:
  %cmp = icmp slt i32 %i, %j
--- a/llvm/test/Analysis/FunctionPropertiesAnalysis/pipeline.ll
+++ b/llvm/test/Analysis/FunctionPropertiesAnalysis/pipeline.ll
@@ -0,0 +1,41 @@
+; REQUIRES: asserts
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='func-properties-stats<pre-opt>' < %s 2>&1 | FileCheck %s --check-prefix=PRE
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='func-properties-stats' < %s 2>&1 | FileCheck %s --check-prefixes=POSTNOOPT
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -O0 < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POSTNOOPT
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -O3 < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='lto<O3>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='lto-pre-link<Os>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='lto-pre-link<O3>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='thinlto<O3>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -enable-detailed-function-properties -disable-output -passes='thinlto-pre-link<O2>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+
+; --- <pre-opt> ---
+; PRE-DAG: 4 func-properties-stats - Number of basic blocks (before optimizations)
+; PRE-DAG: 5 func-properties-stats - Number of instructions (of all types) (before optimizations)
+; PRE-DAG: 4 func-properties-stats - Number of basic block successors (before optimizations)
+
+; --- No <pre-opt> in pass but no optimization passes run ---
+; POSTNOOPT-DAG: 4 func-properties-stats - Number of basic blocks
+; POSTNOOPT-DAG: 5 func-properties-stats - Number of instructions (of all types)
+; POSTNOOPT-DAG: 4 func-properties-stats - Number of basic block successors
+
+; --- Post optimization values ---
+; POST-DAG: 1 func-properties-stats - Number of basic blocks
+; POST-DAG: 1 func-properties-stats - Number of instructions (of all types)
+; POST-NOT: func-properties-stats - Number of basic block successors
+
+define i32 @test_count() {
+entry:
+  ; This branch is trivially resolvable
+  br i1 true, label %then, label %else
+
+then:
+  br label %end
+
+else:
+  br label %end
+
+end:
+  %phi = phi i32 [ 1, %then ], [ 2, %else ]
+  ret i32 %phi
+}
--- a/llvm/test/Analysis/InstCount/instcount.ll
+++ b/llvm/test/Analysis/InstCount/instcount.ll
@@ -1,11 +1,5 @@
 ; REQUIRES: asserts
 ; RUN: opt -stats -passes=instcount -disable-output < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -passes='thinlto<O3>' -disable-output < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -passes='thinlto-pre-link<O2>' -disable-output < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -passes='lto<O1>' -disable-output < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -passes='lto-pre-link<Os>' -disable-output < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -O3 -disable-output < %s 2>&1 | FileCheck %s
-; RUN: opt -stats -O0 -disable-output < %s 2>&1 | FileCheck %s

 ; CHECK-DAG: 10 instcount - Largest number of basic blocks in a single function
 ; CHECK-DAG: 18 instcount - Largest number of instructions in a single function
@@ -17,7 +11,7 @@
 ; CHECK-DAG: 1 instcount - Number of Switch insts
 ; CHECK-DAG: 11 instcount - Number of basic blocks
 ; CHECK-DAG: 2 instcount - Number of non-external functions
-; CHECK-DAG: 19 instcount - Number of instructions (of all types)
+; CHECK-DAG: 19 instcount - Number of instructions of all types

 define void @foo(i32 %i, i32 %j, i32 %n) {
 entry:
--- a/llvm/test/Analysis/InstCount/pipeline.ll
+++ b/llvm/test/Analysis/InstCount/pipeline.ll
@@ -0,0 +1,41 @@
+; REQUIRES: asserts
+; RUN: opt -stats -disable-output -passes='instcount<pre-opt>' < %s 2>&1 | FileCheck %s --check-prefix=PRE
+; RUN: opt -stats -disable-output -passes='instcount' < %s 2>&1 | FileCheck %s --check-prefixes=POSTNOOPT
+; RUN: opt -stats -disable-output -O0 < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POSTNOOPT
+; RUN: opt -stats -disable-output -O3 < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -disable-output -passes='lto<O3>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -disable-output -passes='lto-pre-link<Os>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -disable-output -passes='lto-pre-link<O3>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -disable-output -passes='thinlto<O3>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+; RUN: opt -stats -disable-output -passes='thinlto-pre-link<O2>' < %s 2>&1 | FileCheck %s --check-prefixes=PRE,POST
+
+; --- <pre-opt> ---
+; PRE-DAG: 4 instcount - Number of basic blocks (before optimizations)
+; PRE-DAG: 5 instcount - Number of instructions of all types (before optimizations)
+; PRE-DAG: 1 instcount - Number of CondBr insts (before optimizations)
+
+; --- No <pre-opt> in pass but no optimization passes run ---
+; POSTNOOPT-DAG: 4 instcount - Number of basic blocks
+; POSTNOOPT-DAG: 5 instcount - Number of instructions of all types
+; POSTNOOPT-DAG: 1 instcount - Number of CondBr insts
+
+; --- Post optimization values ---
+; POST-DAG: 1 instcount - Number of basic blocks
+; POST-DAG: 1 instcount - Number of instructions of all types
+; POST-NOT: instcount - Number of CondBr insts
+
+define i32 @test_count() {
+entry:
+  ; This branch is trivially resolvable
+  br i1 true, label %then, label %else
+
+then:
+  br label %end
+
+else:
+  br label %end
+
+end:
+  %phi = phi i32 [ 1, %then ], [ 2, %else ]
+  ret i32 %phi
+}