[LLVM] InstCount pass added when enabling stats (#171658)

Shows the different types of IR instructions when stats are enabled.

Author: InakiVA

llvm/lib/Passes/PassBuilderPipelines.cpp

@@ -21,6 +21,7 @@
 #include "llvm/Analysis/CtxProfAnalysis.h"
 #include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/InlineAdvisor.h"
+#include "llvm/Analysis/InstCount.h"
 #include "llvm/Analysis/ProfileSummaryInfo.h"
 #include "llvm/Analysis/ScopedNoAliasAA.h"
 #include "llvm/Analysis/TypeBasedAliasAnalysis.h"
@@ -411,6 +412,9 @@ void PassBuilder::invokePipelineEarlySimplificationEPCallbacks(
 // Helper to add AnnotationRemarksPass.
 static void addAnnotationRemarksPass(ModulePassManager &MPM) {
   MPM.addPass(createModuleToFunctionPassAdaptor(AnnotationRemarksPass()));
+  // Count the types of instructions used
+  if (AreStatisticsEnabled())
+    MPM.addPass(createModuleToFunctionPassAdaptor(InstCountPass()));
 }
 
 // Helper to check if the current compilation phase is preparing for LTO
@@ -2420,7 +2424,8 @@ PassBuilder::buildO0DefaultPipeline(OptimizationLevel Level,
   if (isLTOPreLink(Phase))
     addRequiredLTOPreLinkPasses(MPM);
 
-  MPM.addPass(createModuleToFunctionPassAdaptor(AnnotationRemarksPass()));
+  // Emit annotation remarks.
+  addAnnotationRemarksPass(MPM);
 
   return MPM;
 }

llvm/test/Other/instcount.ll

@@ -0,0 +1,69 @@
+; 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: 8 instcount - Number of Br insts
+; CHECK-DAG: 6 instcount - Number of Call insts
+; CHECK-DAG: 2 instcount - Number of ICmp insts
+; CHECK-DAG: 1 instcount - Number of Ret insts
+; CHECK-DAG: 1 instcount - Number of Switch insts
+; CHECK-DAG: 10 instcount - Number of basic blocks
+; CHECK-DAG: 1 instcount - Number of non-external functions
+; CHECK-DAG: 18 instcount - Number of instructions (of all types)
+
+
+define void @foo(i32 %i, i32 %j, i32 %n) {
+entry:
+  %cmp = icmp slt i32 %i, %j
+  br i1 %cmp, label %if.then, label %if.end
+
+if.then:
+  call void @f()
+  br label %if.end
+
+if.end:
+  switch i32 %i, label %sw.default [
+    i32 1, label %sw.bb
+    i32 2, label %sw.bb1
+    i32 3, label %sw.bb1
+  ]
+
+sw.bb:
+  call void @g()
+  br label %sw.epilog
+
+sw.bb1:
+  call void @h()
+  br label %sw.epilog
+
+sw.default:
+  call void @k()
+  br label %sw.epilog
+
+sw.epilog:
+  %cmp2 = icmp sgt i32 %i, %n
+  br i1 %cmp2, label %if.then3, label %if.else
+
+if.then3:
+  call void @l()
+  br label %if.end4
+
+if.else:
+  call void @m()
+  br label %if.end4
+
+if.end4:
+  ret void
+}
+
+declare void @f()
+declare void @g()
+declare void @h()
+declare void @k()
+declare void @l()
+declare void @m()