diff options
| -rw-r--r-- | llvm/lib/Target/X86/X86InstrCompiler.td | 1 | ||||
| -rw-r--r-- | llvm/test/CodeGen/X86/TruncAssertZext.ll | 16 |
2 files changed, 17 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86InstrCompiler.td b/llvm/lib/Target/X86/X86InstrCompiler.td index bf25672b2f6..117b6ff2103 100644 --- a/llvm/lib/Target/X86/X86InstrCompiler.td +++ b/llvm/lib/Target/X86/X86InstrCompiler.td @@ -1191,6 +1191,7 @@ def def32 : PatLeaf<(i32 GR32:$src), [{ return N->getOpcode() != ISD::TRUNCATE && N->getOpcode() != TargetOpcode::EXTRACT_SUBREG && N->getOpcode() != ISD::CopyFromReg && + N->getOpcode() != ISD::AssertSext && N->getOpcode() != X86ISD::CMOV; }]>; diff --git a/llvm/test/CodeGen/X86/TruncAssertZext.ll b/llvm/test/CodeGen/X86/TruncAssertZext.ll new file mode 100644 index 00000000000..2d78b5fadc2 --- /dev/null +++ b/llvm/test/CodeGen/X86/TruncAssertZext.ll @@ -0,0 +1,16 @@ +; RUN: llc < %s -O2 -march=x86-64 | FileCheck %s
+; Checks that a zeroing mov is inserted for the trunc/zext pair even when
+; the source of the zext is an AssertSext node
+; PR20494
+
+define i64 @main(i64 %a) {
+; CHECK-LABEL: main
+; CHECK: movl %e{{..}}, %eax
+; CHECK: ret
+ %or = or i64 %a, -2
+ %trunc = trunc i64 %or to i32
+ br label %l
+l:
+ %ext = zext i32 %trunc to i64
+ ret i64 %ext
+}
|
