From 58b1ac76d470eb5faa7e98feae97c4906d4d146e Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Wed, 25 Feb 2009 18:20:01 +0000
Subject: [PATCH] Fix PR3667

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65464 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../Scalar/InstructionCombining.cpp           |  2 +-
 .../2009-02-25-CrashZeroSizeArray.ll          | 38 +++++++++++++++++++
 2 files changed, 39 insertions(+), 1 deletion(-)
 create mode 100644 test/Transforms/InstCombine/2009-02-25-CrashZeroSizeArray.ll

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 62554a5e91f..61ca5de5b86 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -10837,7 +10837,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
         // out, perform the transformation. Note, we don't know whether Scale is
         // signed or not. We'll use unsigned version of division/modulo
         // operation after making sure Scale doesn't have the sign bit set.
-        if (Scale && Scale->getSExtValue() >= 0LL &&
+        if (ArrayEltSize && Scale && Scale->getSExtValue() >= 0LL &&
             Scale->getZExtValue() % ArrayEltSize == 0) {
           Scale = ConstantInt::get(Scale->getType(),
                                    Scale->getZExtValue() / ArrayEltSize);
diff --git a/test/Transforms/InstCombine/2009-02-25-CrashZeroSizeArray.ll b/test/Transforms/InstCombine/2009-02-25-CrashZeroSizeArray.ll
new file mode 100644
index 00000000000..c59c5edcf2d
--- /dev/null
+++ b/test/Transforms/InstCombine/2009-02-25-CrashZeroSizeArray.ll
@@ -0,0 +1,38 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis
+; PR3667
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32"
+target triple = "i386-pc-linux-gnu"
+
+define void @_ada_c32001b(i32 %tmp5) {
+entry:
+	%max289 = select i1 false, i32 %tmp5, i32 0		; <i32> [#uses=1]
+	%tmp6 = mul i32 %max289, 4		; <i32> [#uses=1]
+	%tmp7 = alloca i8, i32 0		; <i8*> [#uses=1]
+	%tmp8 = bitcast i8* %tmp7 to [0 x [0 x i32]]*		; <[0 x [0 x i32]]*> [#uses=1]
+	%tmp11 = load i32* null, align 1		; <i32> [#uses=1]
+	%tmp12 = icmp eq i32 %tmp11, 3		; <i1> [#uses=1]
+	%tmp13 = zext i1 %tmp12 to i8		; <i8> [#uses=1]
+	%tmp14 = ashr i32 %tmp6, 2		; <i32> [#uses=1]
+	%tmp15 = bitcast [0 x [0 x i32]]* %tmp8 to i8*		; <i8*> [#uses=1]
+	%tmp16 = mul i32 %tmp14, 4		; <i32> [#uses=1]
+	%tmp17 = mul i32 1, %tmp16		; <i32> [#uses=1]
+	%tmp18 = getelementptr i8* %tmp15, i32 %tmp17		; <i8*> [#uses=1]
+	%tmp19 = bitcast i8* %tmp18 to [0 x i32]*		; <[0 x i32]*> [#uses=1]
+	%tmp20 = bitcast [0 x i32]* %tmp19 to i32*		; <i32*> [#uses=1]
+	%tmp21 = getelementptr i32* %tmp20, i32 0		; <i32*> [#uses=1]
+	%tmp22 = load i32* %tmp21, align 1		; <i32> [#uses=1]
+	%tmp23 = icmp eq i32 %tmp22, 4		; <i1> [#uses=1]
+	%tmp24 = zext i1 %tmp23 to i8		; <i8> [#uses=1]
+	%toBool709 = icmp ne i8 %tmp13, 0		; <i1> [#uses=1]
+	%toBool710 = icmp ne i8 %tmp24, 0		; <i1> [#uses=1]
+	%tmp25 = and i1 %toBool709, %toBool710		; <i1> [#uses=1]
+	%tmp26 = zext i1 %tmp25 to i8		; <i8> [#uses=1]
+	%toBool711 = icmp ne i8 %tmp26, 0		; <i1> [#uses=1]
+	br i1 %toBool711, label %a, label %b
+
+a:		; preds = %entry
+	ret void
+
+b:		; preds = %entry
+	ret void
+}