[PATCH] D112860: [X86] Fix X32 tail call generation

[Harald van Dijk via Phabricator via llvm-commits]

hvdijk created this revision.
hvdijk added reviewers: RKSimon, MaskRay, craig.topper.
hvdijk added a project: LLVM.
Herald added subscribers: pengfei, hiraditya.
hvdijk requested review of this revision.
Herald added a subscriber: llvm-commits.

The check for whether a zero extension was needed was subtly wrong and saw a value that was already 64 bits, so did not extend.

Fixes PR52357.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D112860

Files:
  llvm/lib/Target/X86/X86ISelLowering.cpp
  llvm/test/CodeGen/X86/tailcall-structfp.ll


Index: llvm/test/CodeGen/X86/tailcall-structfp.ll
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/X86/tailcall-structfp.ll
@@ -0,0 +1,20 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnux32 -tailcallopt | FileCheck %s
+declare { i64, void ()* } @a()
+define void @b() {
+; CHECK-LABEL: b:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    pushq %rax
+; CHECK-NEXT:    .cfi_def_cfa_offset 16
+; CHECK-NEXT:    callq a at PLT
+; CHECK-NEXT:    movl %edx, %eax
+; CHECK-NEXT:    callq *%rax
+; CHECK-NEXT:    popq %rax
+; CHECK-NEXT:    .cfi_def_cfa_offset 8
+; CHECK-NEXT:    retq
+entry:
+  %0 = tail call { i64, void ()* } @a()
+  %1 = extractvalue { i64, void ()* } %0, 1
+  tail call void %1()
+  ret void
+}
Index: llvm/lib/Target/X86/X86ISelLowering.cpp
===================================================================
--- llvm/lib/Target/X86/X86ISelLowering.cpp
+++ llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -4531,7 +4531,7 @@
     // address into a register.
     Callee = LowerGlobalOrExternal(Callee, DAG, /*ForCall=*/true);
   } else if (Subtarget.isTarget64BitILP32() &&
-             Callee->getValueType(0) == MVT::i32) {
+             Callee.getValueType() == MVT::i32) {
     // Zero-extend the 32-bit Callee address into a 64-bit according to x32 ABI
     Callee = DAG.getNode(ISD::ZERO_EXTEND, dl, MVT::i64, Callee);
   }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D112860.383542.patch
Type: text/x-patch
Size: 1480 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20211030/e791bb0c/attachment.bin>