Skip to content

[TailCallElim] Don’t mark llvm.stackrestore with tail-call #101352

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 5 commits into from
Aug 5, 2024
Merged

[TailCallElim] Don’t mark llvm.stackrestore with tail-call #101352

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
89cdac4
[BasicAA] MemCpyOpt fix on tail stackrestore
scui-ibm Jul 31, 2024
23bce05
Revert "[BasicAA] MemCpyOpt fix on tail stackrestore"
scui-ibm Aug 2, 2024
b8f0374
Don't mark tail call for stackrestore
scui-ibm Aug 2, 2024
8aa44be
Fix comments
scui-ibm Aug 5, 2024
3fd2b2b
Minor change to address review comments
scui-ibm Aug 5, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 6 additions & 0 deletions llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -243,6 +243,12 @@ static bool markTails(Function &F, OptimizationRemarkEmitter *ORE) {
isa<PseudoProbeInst>(&I))
continue;

// Bail out for intrinsic stackrestore call because it can modify
// unescaped allocas.
if (auto *II = dyn_cast<IntrinsicInst>(CI))
if (II->getIntrinsicID() == Intrinsic::stackrestore)
continue;

// Special-case operand bundles "clang.arc.attachedcall", "ptrauth", and
// "kcfi".
bool IsNoTail = CI->isNoTailCall() ||
Expand Down
14 changes: 14 additions & 0 deletions llvm/test/Transforms/TailCallElim/stackrestore.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,14 @@
; RUN: opt -S -passes=tailcallelim < %s | FileCheck %s

define void @foo() {
; CHECK-LABEL: define void @foo()
; CHECK-NOT: tail call void @llvm.stackrestore.p0
;
entry:
%0 = call ptr @llvm.stacksave.p0()
call void @llvm.stackrestore.p0(ptr %0)
ret void
}

declare ptr @llvm.stacksave.p0()
declare void @llvm.stackrestore.p0(ptr)
Loading