1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
|
From 98a42416c93477f430012fc1343a393bccab85b2 Mon Sep 17 00:00:00 2001
From: Valentin Churavy <v.churavy@gmail.com>
Date: Mon, 21 May 2018 16:18:54 -0400
Subject: [PATCH] [InstCombine] fix crash due to ignored addrspacecast
Summary:
Part of the InstCombine code for simplifying GEPs looks through
addrspacecasts. However, this was done by updating a variable
also used by the next transformation, for marking GEPs as
inbounds. This led to replacing a GEP with a similar instruction
in a different addrspace, which caused an assertion failure in RAUW.
This caused julia issue https://github.com/JuliaLang/julia/issues/27055
Patch by Jeff Bezanson <jeff@juliacomputing.com>
Adapted to 6.0 by Valentin Churavy <vchuravy@mit.edu>
Differential Revision: https://reviews.llvm.org/D46722
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332302 91177308-0d34-0410-b5e6-96231b3b80d8
---
.../InstCombine/InstructionCombining.cpp | 5 +++--
test/Transforms/InstCombine/gep-addrspace.ll | 19 +++++++++++++++++++
2 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index 35ed592ac07..8fa7d0684b9 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -1947,13 +1947,14 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
// addrspacecast between types is canonicalized as a bitcast, then an
// addrspacecast. To take advantage of the below bitcast + struct GEP, look
// through the addrspacecast.
+ Value *ASCStrippedPtrOp = PtrOp;
if (AddrSpaceCastInst *ASC = dyn_cast<AddrSpaceCastInst>(PtrOp)) {
// X = bitcast A addrspace(1)* to B addrspace(1)*
// Y = addrspacecast A addrspace(1)* to B addrspace(2)*
// Z = gep Y, <...constant indices...>
// Into an addrspacecasted GEP of the struct.
if (BitCastInst *BC = dyn_cast<BitCastInst>(ASC->getOperand(0)))
- PtrOp = BC;
+ ASCStrippedPtrOp = BC;
}
/// See if we can simplify:
@@ -1961,7 +1962,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
/// Y = gep X, <...constant indices...>
/// into a gep of the original struct. This is important for SROA and alias
/// analysis of unions. If "A" is also a bitcast, wait for A/X to be merged.
- if (BitCastInst *BCI = dyn_cast<BitCastInst>(PtrOp)) {
+ if (BitCastInst *BCI = dyn_cast<BitCastInst>(ASCStrippedPtrOp)) {
Value *Operand = BCI->getOperand(0);
PointerType *OpType = cast<PointerType>(Operand->getType());
unsigned OffsetBits = DL.getPointerTypeSizeInBits(GEP.getType());
diff --git a/test/Transforms/InstCombine/gep-addrspace.ll b/test/Transforms/InstCombine/gep-addrspace.ll
index aa46ea67130..4a4951dee7f 100644
--- a/test/Transforms/InstCombine/gep-addrspace.ll
+++ b/test/Transforms/InstCombine/gep-addrspace.ll
@@ -32,3 +32,22 @@ entry:
ret void
}
+declare void @escape_alloca(i16*)
+
+; check that addrspacecast is not ignored (leading to an assertion failure)
+; when trying to mark a GEP as inbounds
+define { i8, i8 } @inbounds_after_addrspacecast() {
+top:
+; CHECK-LABEL: @inbounds_after_addrspacecast
+ %0 = alloca i16, align 2
+ call void @escape_alloca(i16* %0)
+ %tmpcast = bitcast i16* %0 to [2 x i8]*
+; CHECK: addrspacecast [2 x i8]* %tmpcast to [2 x i8] addrspace(11)*
+ %1 = addrspacecast [2 x i8]* %tmpcast to [2 x i8] addrspace(11)*
+; CHECK: getelementptr [2 x i8], [2 x i8] addrspace(11)* %1, i64 0, i64 1
+ %2 = getelementptr [2 x i8], [2 x i8] addrspace(11)* %1, i64 0, i64 1
+; CHECK: addrspace(11)
+ %3 = load i8, i8 addrspace(11)* %2, align 1
+ %.fca.1.insert = insertvalue { i8, i8 } zeroinitializer, i8 %3, 1
+ ret { i8, i8 } %.fca.1.insert
+}
--
2.17.0
|
