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Fix 40056: Prevent outlining of blocks with token type instructions (… #9000

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22 changes: 21 additions & 1 deletion llvm/lib/Transforms/IPO/HotColdSplitting.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -39,6 +39,7 @@
#include "llvm/IR/CFG.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/EHPersonalities.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
Expand Down Expand Up @@ -136,10 +137,24 @@ static bool mayExtractBlock(const BasicBlock &BB) {
//
// Resumes that are not reachable from a cleanup landing pad are considered to
// be unreachable. It’s not safe to split them out either.

if (BB.hasAddressTaken() || BB.isEHPad())
return false;
auto Term = BB.getTerminator();
return !isa<InvokeInst>(Term) && !isa<ResumeInst>(Term);
if (isa<InvokeInst>(Term) || isa<ResumeInst>(Term))
return false;

// Do not outline basic blocks that have token type instructions. e.g.,
// exception:
// %0 = cleanuppad within none []
// call void @"?terminate@@YAXXZ"() [ "funclet"(token %0) ]
// br label %continue-exception
if (llvm::any_of(
BB, [](const Instruction &I) { return I.getType()->isTokenTy(); })) {
return false;
}

return true;
}

/// Mark \p F cold. Based on this assumption, also optimize it for minimum size.
Expand Down Expand Up @@ -203,6 +218,11 @@ bool HotColdSplitting::shouldOutlineFrom(const Function &F) const {
F.hasFnAttribute(Attribute::SanitizeMemory))
return false;

// Do not outline scoped EH personality functions.
if (F.hasPersonalityFn())
if (isScopedEHPersonality(classifyEHPersonality(F.getPersonalityFn())))
return false;

return true;
}

Expand Down
72 changes: 72 additions & 0 deletions llvm/test/Transforms/HotColdSplit/pr40056.ll
Original file line number Diff line number Diff line change
@@ -0,0 +1,72 @@
; RUN: opt -passes=hotcoldsplit -hotcoldsplit-threshold=-1 -S < %s | FileCheck %s
; Hot cold splitting should not outline:
; 1. Basic blocks with token type instructions
; 2. Functions with scoped EH personality

target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-windows-msvc19.0.0"

; CHECK-LABEL: define {{.*}}@with_funclet
; CHECK-NOT: with_funclet.cold
define void @with_funclet() personality ptr @__CxxFrameHandler3 {
entry:
invoke void @fYAXXZ()
to label %normal unwind label %exception

normal: ; preds = %entry
ret void

exception: ; preds = %entry
%0 = cleanuppad within none []
call void @terminateYAXXZ() [ "funclet"(token %0) ]
br label %continueexception

continueexception: ; preds = %exception
ret void
}

; CHECK-LABEL: define {{.*}}@with_personality
; CHECK-NOT: with_personality.cold
define void @with_personality(i32 %cond) personality ptr @__CxxFrameHandler3 {
entry:
%cond.addr = alloca i32
store i32 %cond, ptr %cond.addr
%0 = load i32, ptr %cond.addr
%tobool = icmp ne i32 %0, 0
br i1 %tobool, label %if.then, label %if.end2

if.then: ; preds = %entry
%1 = load i32, ptr %cond.addr
%cmp = icmp sgt i32 %1, 10
br i1 %cmp, label %if.then1, label %if.else

if.then1: ; preds = %if.then
call void @sideeffect(i32 0)
br label %if.end

if.else: ; preds = %if.then
call void @sideeffect(i32 1)
br label %if.end

if.end: ; preds = %if.else, %if.then1
call void (...) @sink()
ret void

if.end2: ; preds = %entry
call void @sideeffect(i32 2)
ret void
}

declare i32 @__CxxFrameHandler3(...)

declare void @fYAXXZ()

declare void @bar() #0

declare void @terminateYAXXZ()

declare void @sideeffect(i32)

declare void @sink(...) #0

attributes #0 = { cold }