From: Hans Wennborg <hans@hanshq.net>
Date: Mon, 28 Apr 2014 17:40:03 +0000 (+0000)
Subject: InstCombine: don't drop 'inalloca' in PromoteCastOfAllocation (PR19569)
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6426666f6561785d7d5a6d1904f6df11df655082;p=oota-llvm.git

InstCombine: don't drop 'inalloca' in PromoteCastOfAllocation (PR19569)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207426 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/InstCombine/InstCombineCasts.cpp b/lib/Transforms/InstCombine/InstCombineCasts.cpp
index de8b94d6c2e..70b0a8343f6 100644
--- a/lib/Transforms/InstCombine/InstCombineCasts.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -143,6 +143,7 @@ Instruction *InstCombiner::PromoteCastOfAllocation(BitCastInst &CI,
   AllocaInst *New = AllocaBuilder.CreateAlloca(CastElTy, Amt);
   New->setAlignment(AI.getAlignment());
   New->takeName(&AI);
+  New->setUsedWithInAlloca(AI.isUsedWithInAlloca());
 
   // If the allocation has multiple real uses, insert a cast and change all
   // things that used it to use the new cast.  This will also hack on CI, but it
diff --git a/test/Transforms/InstCombine/alloca.ll b/test/Transforms/InstCombine/alloca.ll
index ae1cfa1ed2f..6d0c131c51e 100644
--- a/test/Transforms/InstCombine/alloca.ll
+++ b/test/Transforms/InstCombine/alloca.ll
@@ -129,3 +129,24 @@ define void @test8() {
   call void (...)* @use(i32* %x)
   ret void
 }
+
+; PR19569
+%struct_type = type { i32, i32 }
+declare void @test9_aux(<{ %struct_type }>* inalloca)
+declare i8* @llvm.stacksave()
+declare void @llvm.stackrestore(i8*)
+
+define void @test9(%struct_type* %a) {
+; CHECK-LABEL: @test9(
+entry:
+  %inalloca.save = call i8* @llvm.stacksave()
+  %argmem = alloca inalloca <{ %struct_type }>
+; CHECK: alloca inalloca i64, align 8
+  %0 = getelementptr inbounds <{ %struct_type }>* %argmem, i32 0, i32 0
+  %1 = bitcast %struct_type* %0 to i8*
+  %2 = bitcast %struct_type* %a to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %1, i8* %2, i32 8, i32 4, i1 false)
+  call void @test9_aux(<{ %struct_type }>* inalloca %argmem)
+  call void @llvm.stackrestore(i8* %inalloca.save)
+  ret void
+}