From 269ffdac4e354b58cb627a45a9ffe01fb967004a Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault@amd.com>
Date: Tue, 6 Dec 2016 23:18:06 +0000
Subject: [PATCH] AMDGPU: Fix crash on i16 constant expression

llvm-svn: 288861
---
 llvm/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp    |  5 ++--
 .../AMDGPU/amdgpu-codegenprepare-i16-to-i32.ll     | 28 ++++++++++++++++++++++
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp b/llvm/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp
index b427de1..2e8db08 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp
@@ -146,9 +146,10 @@ public:
 
 Value *AMDGPUCodeGenPrepare::copyFlags(
     const BinaryOperator &I, Value *V) const {
-  assert(isa<BinaryOperator>(V) && "V must be binary operation");
+  BinaryOperator *BinOp = dyn_cast<BinaryOperator>(V);
+  if (!BinOp) // Possibly constant expression.
+    return V;
 
-  BinaryOperator *BinOp = cast<BinaryOperator>(V);
   if (isa<OverflowingBinaryOperator>(BinOp)) {
     BinOp->setHasNoSignedWrap(I.hasNoSignedWrap());
     BinOp->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
diff --git a/llvm/test/CodeGen/AMDGPU/amdgpu-codegenprepare-i16-to-i32.ll b/llvm/test/CodeGen/AMDGPU/amdgpu-codegenprepare-i16-to-i32.ll
index 5444b74a..13e4192 100644
--- a/llvm/test/CodeGen/AMDGPU/amdgpu-codegenprepare-i16-to-i32.ll
+++ b/llvm/test/CodeGen/AMDGPU/amdgpu-codegenprepare-i16-to-i32.ll
@@ -533,6 +533,27 @@ define i16 @add_i16(i16 %a, i16 %b) {
   ret i16 %r
 }
 
+; GCN-LABEL: @constant_add_i16(
+; VI: ret i16 3
+define i16 @constant_add_i16() {
+  %r = add i16 1, 2
+  ret i16 %r
+}
+
+; GCN-LABEL: @constant_add_nsw_i16(
+; VI: ret i16 3
+define i16 @constant_add_nsw_i16() {
+  %r = add nsw i16 1, 2
+  ret i16 %r
+}
+
+; GCN-LABEL: @constant_add_nuw_i16(
+; VI: ret i16 3
+define i16 @constant_add_nuw_i16() {
+  %r = add nsw i16 1, 2
+  ret i16 %r
+}
+
 ; GCN-LABEL: @add_nsw_i16(
 ; SI: %r = add nsw i16 %a, %b
 ; SI-NEXT: ret i16 %r
@@ -806,6 +827,13 @@ define i16 @ashr_exact_i16(i16 %a, i16 %b) {
   ret i16 %r
 }
 
+; GCN-LABEL: @constant_lshr_exact_i16(
+; VI: ret i16 2
+define i16 @constant_lshr_exact_i16(i16 %a, i16 %b) {
+  %r = lshr exact i16 4, 1
+  ret i16 %r
+}
+
 ; GCN-LABEL: @and_i16(
 ; SI: %r = and i16 %a, %b
 ; SI-NEXT: ret i16 %r
-- 
2.7.4