From 90dfbeef5982ecfb5523b48f3c301bea033e5c3d Mon Sep 17 00:00:00 2001 From: Wei Mi Date: Wed, 10 Mar 2021 20:13:52 -0800 Subject: [PATCH] [IndirectCallPromotion] Don't strip ".__uniq." suffix when it strips ".llvm." suffix. Currently IndirectCallPromotion simply strip everything after the first "." in LTO mode, in order to match the symbol name and the name with ".llvm." suffix in the value profile. However, if -funique-internal-linkage-names and thinlto are both enabled, the name may have both ".__uniq." suffix and ".llvm." suffix, and the current mechanism will strip them both, which is unexpected. The patch fixes the problem. Differential Revision: https://reviews.llvm.org/D98389 --- llvm/lib/ProfileData/InstrProf.cpp | 33 +++++-- .../indirect_call_promotion_unique.ll | 95 +++++++++++++++++++ 2 files changed, 118 insertions(+), 10 deletions(-) create mode 100644 llvm/test/Transforms/PGOProfile/indirect_call_promotion_unique.ll diff --git a/llvm/lib/ProfileData/InstrProf.cpp b/llvm/lib/ProfileData/InstrProf.cpp index f1167bb455795..944b937f6fcfd 100644 --- a/llvm/lib/ProfileData/InstrProf.cpp +++ b/llvm/lib/ProfileData/InstrProf.cpp @@ -353,16 +353,29 @@ Error InstrProfSymtab::create(Module &M, bool InLTO) { return E; MD5FuncMap.emplace_back(Function::getGUID(PGOFuncName), &F); // In ThinLTO, local function may have been promoted to global and have - // suffix added to the function name. We need to add the stripped function - // name to the symbol table so that we can find a match from profile. - if (InLTO) { - auto pos = PGOFuncName.find('.'); - if (pos != std::string::npos) { - const std::string &OtherFuncName = PGOFuncName.substr(0, pos); - if (Error E = addFuncName(OtherFuncName)) - return E; - MD5FuncMap.emplace_back(Function::getGUID(OtherFuncName), &F); - } + // suffix ".llvm." added to the function name. We need to add the + // stripped function name to the symbol table so that we can find a match + // from profile. + // + // We may have other suffixes similar as ".llvm." which are needed to + // be stripped before the matching, but ".__uniq." suffix which is used + // to differentiate internal linkage functions in different modules + // should be kept. Now this is the only suffix with the pattern ".xxx" + // which is kept before matching. + const std::string UniqSuffix = ".__uniq."; + auto pos = PGOFuncName.find(UniqSuffix); + // Search '.' after ".__uniq." if ".__uniq." exists, otherwise + // search '.' from the beginning. + if (pos != std::string::npos) + pos += UniqSuffix.length(); + else + pos = 0; + pos = PGOFuncName.find('.', pos); + if (pos != std::string::npos) { + const std::string &OtherFuncName = PGOFuncName.substr(0, pos); + if (Error E = addFuncName(OtherFuncName)) + return E; + MD5FuncMap.emplace_back(Function::getGUID(OtherFuncName), &F); } } Sorted = false; diff --git a/llvm/test/Transforms/PGOProfile/indirect_call_promotion_unique.ll b/llvm/test/Transforms/PGOProfile/indirect_call_promotion_unique.ll new file mode 100644 index 0000000000000..beee6b9eef9db --- /dev/null +++ b/llvm/test/Transforms/PGOProfile/indirect_call_promotion_unique.ll @@ -0,0 +1,95 @@ +; RUN: opt < %s -passes=pgo-icall-prom -S | FileCheck %s + +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@foo = common global i32 ()* null, align 8 + +; The names on the IR and in the profile are both "func1". +define i32 @func1() { +entry: + ret i32 1 +} + +define i32 @bar1() { +entry: + %tmp1 = load i32 ()*, i32 ()** @foo, align 8 +; CHECK: icmp eq i32 ()* %tmp1, @func1 + %call = call i32 %tmp1(), !prof !1 + ret i32 %call +} + +; The name on the IR has ".llvm." suffix: "func2.llvm.10895321227755557127". +; The name in the profile has no ".llvm." suffix: "func2". +define i32 @func2.llvm.10895321227755557127() { +entry: + ret i32 1 +} + +define i32 @bar2() { +entry: + %tmp2 = load i32 ()*, i32 ()** @foo, align 8 +; CHECK: icmp eq i32 ()* %tmp2, @func2.llvm.10895321227755557127 + %call = call i32 %tmp2(), !prof !2 + ret i32 %call +} + +; The names on the IR and in the profile are both +; "func3.__uniq.258901567653530696343884446915951489119". +define i32 @func3.__uniq.258901567653530696343884446915951489119() { +entry: + ret i32 2 +} + +define i32 @bar3() { +entry: + %tmp3 = load i32 ()*, i32 ()** @foo, align 8 +; CHECK: icmp eq i32 ()* %tmp3, @func3.__uniq.258901567653530696343884446915951489119 + %call = call i32 %tmp3(), !prof !3 + ret i32 %call +} + +; The name on the IR has ".__uniq." and ".llvm." suffix: +; "func4.__uniq.140291095734751150107370763113257199296.llvm.10650195578168450516". +; The name in the profile has ".__uniq." but no ".llvm." suffix: +; "func4.__uniq.140291095734751150107370763113257199296". +define i32 @func4.__uniq.140291095734751150107370763113257199296.llvm.10650195578168450516() { +entry: + ret i32 3 +} + +define i32 @bar4() { +entry: + %tmp4 = load i32 ()*, i32 ()** @foo, align 8 +; CHECK: icmp eq i32 ()* %tmp4, @func4.__uniq.140291095734751150107370763113257199296.llvm.10650195578168450516 + %call = call i32 %tmp4(), !prof !4 + ret i32 %call +} + +; The name on the IR has ".__uniq.", ".part." and ".llvm." suffix: +; "func4.__uniq.127882361580787111523790444488985774976.part.818292359123831.llvm.10650195578168450516". +; The name in the profile has ".__uniq." but no ".llvm." and no ".part." suffix: +; "func4.__uniq.127882361580787111523790444488985774976". +define i32 @func5.__uniq.127882361580787111523790444488985774976.part.818292359123831.llvm.10650195578168450516() { +entry: + ret i32 3 +} + +define i32 @bar5() { +entry: + %tmp5 = load i32 ()*, i32 ()** @foo, align 8 +; CHECK: icmp eq i32 ()* %tmp5, @func5.__uniq.127882361580787111523790444488985774976.part.818292359123831.llvm.10650195578168450516 + %call = call i32 %tmp5(), !prof !5 + ret i32 %call +} + +; GUID of "func1" is -2545542355363006406. +; GUID of "func2" is -4377547752858689819. +; GUID of "func3.__uniq.258901567653530696343884446915951489119" is 8271224222042874235. +; GUID of "func4.__uniq.140291095734751150107370763113257199296" is 1491826207425861106. +; GUID of "func5.__uniq.127882361580787111523790444488985774976" is -4238550483433487304. +!1 = !{!"VP", i32 0, i64 1600, i64 -2545542355363006406, i64 1600} +!2 = !{!"VP", i32 0, i64 1600, i64 -4377547752858689819, i64 1600} +!3 = !{!"VP", i32 0, i64 1600, i64 8271224222042874235, i64 1600} +!4 = !{!"VP", i32 0, i64 1600, i64 1491826207425861106, i64 1600} +!5 = !{!"VP", i32 0, i64 1600, i64 -4238550483433487304, i64 1600}