Fix crash with CSPGO

see also https://github.com/llvm/llvm-project/issues/97962 for the upstream
bug report.

Signed-off-by: Kefu Chai <tchaikov@gmail.com>
This commit is contained in:
Kefu Chai 2024-08-31 10:31:53 +08:00
parent 8ed822b44a
commit 3ae2d14ce5
2 changed files with 97 additions and 0 deletions

View file

@ -0,0 +1,90 @@
From 46a4132e167aa44d8ec7776262ce2a0e6d47de59 Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@scylladb.com>
Date: Mon, 26 Aug 2024 17:56:45 +0300
Subject: [PATCH] [Instrumentation] Fix EdgeCounts vector size in
SetBranchWeights (#99064)
---
---
.../Instrumentation/PGOInstrumentation.cpp | 14 +++++--
.../Coroutines/coro-pgo-setbranchweights.ll | 42 +++++++++++++++++++
2 files changed, 52 insertions(+), 4 deletions(-)
create mode 100644 test/Transforms/Coroutines/coro-pgo-setbranchweights.ll
diff --git a/lib/Transforms/Instrumentation/PGOInstrumentation.cpp b/lib/Transforms/Instrumentation/PGOInstrumentation.cpp
index c20fc942e..41025b296 100644
--- a/llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp
+++ b/llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp
@@ -1571,11 +1571,17 @@ void PGOUseFunc::setBranchWeights() {
// We have a non-zero Branch BB.
const PGOUseBBInfo &BBCountInfo = getBBInfo(&BB);
- unsigned Size = BBCountInfo.OutEdges.size();
- SmallVector<uint64_t, 2> EdgeCounts(Size, 0);
+
+ // SuccessorCount can be greater than OutEdgesCount, because
+ // removed edges don't appear in OutEdges.
+ unsigned OutEdgesCount = BBCountInfo.OutEdges.size();
+ unsigned SuccessorCount = BB.getTerminator()->getNumSuccessors();
+ assert(OutEdgesCount <= SuccessorCount);
+
+ SmallVector<uint64_t, 2> EdgeCounts(SuccessorCount, 0);
uint64_t MaxCount = 0;
- for (unsigned s = 0; s < Size; s++) {
- const PGOUseEdge *E = BBCountInfo.OutEdges[s];
+ for (unsigned It = 0; It < OutEdgesCount; It++) {
+ const PGOUseEdge *E = BBCountInfo.OutEdges[It];
const BasicBlock *SrcBB = E->SrcBB;
const BasicBlock *DestBB = E->DestBB;
if (DestBB == nullptr)
diff --git a/test/Transforms/Coroutines/coro-pgo-setbranchweights.ll b/test/Transforms/Coroutines/coro-pgo-setbranchweights.ll
new file mode 100644
index 000000000..4f5f93660
--- /dev/null
+++ b/test/Transforms/Coroutines/coro-pgo-setbranchweights.ll
@@ -0,0 +1,42 @@
+; RUN: rm -rf %t && split-file %s %t
+
+; RUN: llvm-profdata merge %t/a.proftext -o %t/a.profdata
+; RUN: opt < %t/a.ll --passes=pgo-instr-use -pgo-test-profile-file=%t/a.profdata
+
+;--- a.ll
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-redhat-linux-gnu"
+
+define void @_bar() presplitcoroutine personality ptr null {
+ %1 = call token @llvm.coro.save(ptr null)
+ %2 = call i8 @llvm.coro.suspend(token none, i1 false)
+ switch i8 %2, label %5 [
+ i8 0, label %3
+ i8 1, label %4
+ ]
+
+3: ; preds = %0
+ ret void
+
+4: ; preds = %0
+ ret void
+
+5: ; preds = %0
+ ret void
+}
+
+declare token @llvm.coro.save(ptr)
+
+declare i8 @llvm.coro.suspend(token, i1)
+
+;--- a.proftext
+# IR level Instrumentation Flag
+:ir
+
+_bar
+# Func Hash:
+1063705160175073211
+# Num Counters:
+2
+1
+0
--
2.46.0

View file

@ -113,6 +113,9 @@ Source5: https://github.com/llvm/llvm-project/releases/download/llvmorg-%{maj_ve
Source6: release-keys.asc
%endif
# Backport of PGO fix of https://github.com/llvm/llvm-project/issues/97962
Patch1: 0001-Instrumentation-Fix-EdgeCounts-vector-size-in-SetBra.patch
# RHEL-specific patch to avoid unwanted python3-myst-parser dep
Patch101: 0101-Deactivate-markdown-doc.patch
@ -598,6 +601,10 @@ fi
%changelog
* Sat Aug 31 2024 Kefu Chai <kefu.chai@scylladb.com> - 18.1.8-2
- Fix a crash in context senstive PGO (CSPGO) build by applying the patch
of https://github.com/llvm/llvm-project/commit/ffd337b995658266d83e15630d656e57882bcf0d
* Thu Jul 11 2024 Jesus Checa Hidalgo <jchecahi@redhat.com> - 18.1.8-1
- Update to LLVM 18.1.8