Index: llvm/trunk/lib/Transforms/IPO/HotColdSplitting.cpp =================================================================== --- llvm/trunk/lib/Transforms/IPO/HotColdSplitting.cpp +++ llvm/trunk/lib/Transforms/IPO/HotColdSplitting.cpp @@ -144,8 +144,10 @@ } /// Mark \p F cold. Based on this assumption, also optimize it for minimum size. +/// If \p UpdateEntryCount is true (set when this is a new split function and +/// module has profile data), set entry count to 0 to ensure treated as cold. /// Return true if the function is changed. -static bool markFunctionCold(Function &F) { +static bool markFunctionCold(Function &F, bool UpdateEntryCount = false) { assert(!F.hasFnAttribute(Attribute::OptimizeNone) && "Can't mark this cold"); bool Changed = false; if (!F.hasFnAttribute(Attribute::Cold)) { @@ -156,6 +158,13 @@ F.addFnAttr(Attribute::MinSize); Changed = true; } + if (UpdateEntryCount) { + // Set the entry count to 0 to ensure it is placed in the unlikely text + // section when function sections are enabled. + F.setEntryCount(0); + Changed = true; + } + return Changed; } @@ -340,7 +349,7 @@ } CI->setIsNoInline(); - markFunctionCold(*OutF); + markFunctionCold(*OutF, BFI != nullptr); LLVM_DEBUG(llvm::dbgs() << "Outlined Region: " << *OutF); ORE.emit([&]() { Index: llvm/trunk/test/Transforms/HotColdSplit/coldentrycount.ll =================================================================== --- llvm/trunk/test/Transforms/HotColdSplit/coldentrycount.ll +++ llvm/trunk/test/Transforms/HotColdSplit/coldentrycount.ll @@ -0,0 +1,43 @@ +; Test to ensure that split cold function gets 0 entry count profile +; metadata when compiling with pgo. + +; RUN: opt -hotcoldsplit -hotcoldsplit-threshold=0 -S < %s | FileCheck %s + +target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-apple-macosx10.14.0" + +; CHECK-LABEL: @fun +; CHECK: call void @fun.cold.1 +define void @fun() !prof !14 { +entry: + br i1 undef, label %if.then, label %if.else + +if.then: + ret void + +if.else: + call void @sink() + ret void +} + +declare void @sink() cold + +; CHECK: define {{.*}} @fun.cold.1{{.*}} ![[PROF:[0-9]+]] +; CHECK: ![[PROF]] = !{!"function_entry_count", i64 0} + +!llvm.module.flags = !{!0} +!0 = !{i32 1, !"ProfileSummary", !1} +!1 = !{!2, !3, !4, !5, !6, !7, !8, !9} +!2 = !{!"ProfileFormat", !"InstrProf"} +!3 = !{!"TotalCount", i64 10000} +!4 = !{!"MaxCount", i64 10} +!5 = !{!"MaxInternalCount", i64 1} +!6 = !{!"MaxFunctionCount", i64 1000} +!7 = !{!"NumCounts", i64 3} +!8 = !{!"NumFunctions", i64 3} +!9 = !{!"DetailedSummary", !10} +!10 = !{!11, !12, !13} +!11 = !{i32 10000, i64 100, i32 1} +!12 = !{i32 999000, i64 100, i32 1} +!13 = !{i32 999999, i64 1, i32 2} +!14 = !{!"function_entry_count", i64 100}