From 8abb8c6ff525a40f8379ce91c80974987a5329c2 Mon Sep 17 00:00:00 2001
From: Owen Anderson <resistor@mac.com>
Date: Thu, 7 Aug 2014 21:07:35 +0000
Subject: [PATCH] Fix a case in SROA where lifetime intrinsics could inhibit
 alloca promotion.  In this case, the code path dealing with vector promotion
 was missing the explicit checks for lifetime intrinsics that were present on
 the corresponding integer promotion path.

llvm-svn: 215148
---
 lib/Transforms/Scalar/SROA.cpp                |  4 +++
 .../SROA/vector-lifetime-intrinsic.ll         | 31 +++++++++++++++++++
 2 files changed, 35 insertions(+)
 create mode 100644 test/Transforms/SROA/vector-lifetime-intrinsic.ll

diff --git a/lib/Transforms/Scalar/SROA.cpp b/lib/Transforms/Scalar/SROA.cpp
index 735dd632f01..2ed4c371618 100644
--- a/lib/Transforms/Scalar/SROA.cpp
+++ b/lib/Transforms/Scalar/SROA.cpp
@@ -1659,6 +1659,10 @@ static bool isVectorPromotionViableForSlice(
       return false;
     if (!I->isSplittable())
       return false; // Skip any unsplittable intrinsics.
+  } else if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(U->getUser())) {
+    if (II->getIntrinsicID() != Intrinsic::lifetime_start &&
+        II->getIntrinsicID() != Intrinsic::lifetime_end)
+      return false;
   } else if (U->get()->getType()->getPointerElementType()->isStructTy()) {
     // Disable vector promotion when there are loads or stores of an FCA.
     return false;
diff --git a/test/Transforms/SROA/vector-lifetime-intrinsic.ll b/test/Transforms/SROA/vector-lifetime-intrinsic.ll
new file mode 100644
index 00000000000..30c93b054ec
--- /dev/null
+++ b/test/Transforms/SROA/vector-lifetime-intrinsic.ll
@@ -0,0 +1,31 @@
+; RUN: opt -sroa -S < %s | FileCheck %s
+
+target datalayout = "e-p:64:32-i64:32-v32:32-n32-S64"
+
+; Function Attrs: nounwind
+declare void @llvm.lifetime.start(i64, i8* nocapture) #0
+
+; Function Attrs: nounwind
+declare void @llvm.lifetime.end(i64, i8* nocapture) #0
+
+; CHECK: @wombat
+; CHECK-NOT: alloca
+; CHECK: ret void
+define void @wombat(<4 x float> %arg1) {
+bb:
+  %tmp = alloca <4 x float>, align 16
+  %tmp8 = bitcast <4 x float>* %tmp to i8*
+  call void @llvm.lifetime.start(i64 16, i8* %tmp8)
+  store <4 x float> %arg1, <4 x float>* %tmp, align 16
+  %tmp17 = bitcast <4 x float>* %tmp to <3 x float>*
+  %tmp18 = load <3 x float>* %tmp17
+  %tmp20 = bitcast <4 x float>* %tmp to i8*
+  call void @llvm.lifetime.end(i64 16, i8* %tmp20)
+  call void @wombat3(<3 x float> %tmp18)
+  ret void
+}
+
+; Function Attrs: nounwind
+declare void @wombat3(<3 x float>) #0
+
+attributes #0 = { nounwind }