[llvm] r354403 - [GVN] Fix a crash bug w/non-integral pointers and memtransfers
Philip Reames via llvm-commits
llvm-commits at lists.llvm.org
Tue Feb 19 15:49:38 PST 2019
Author: reames
Date: Tue Feb 19 15:49:38 2019
New Revision: 354403
URL: http://llvm.org/viewvc/llvm-project?rev=354403&view=rev
Log:
[GVN] Fix a crash bug w/non-integral pointers and memtransfers
Problem is very similiar to the one fixed for memsets in r354399, we try to coerce a value to non-integral type, and then crash while try to do so. Since we shouldn't be doing such coercions to start with, easy fix. From inspection, I see two other cases which look to be similiar and will follow up with most test cases and fixes if confirmed.
Modified:
llvm/trunk/lib/Transforms/Utils/VNCoercion.cpp
llvm/trunk/test/Transforms/GVN/non-integral-pointers.ll
Modified: llvm/trunk/lib/Transforms/Utils/VNCoercion.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/VNCoercion.cpp?rev=354403&r1=354402&r2=354403&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/VNCoercion.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/VNCoercion.cpp Tue Feb 19 15:49:38 2019
@@ -300,6 +300,11 @@ int analyzeLoadFromClobberingMemInst(Typ
if (Offset == -1)
return Offset;
+ // Don't coerce non-integral pointers to integers or vice versa.
+ if (DL.isNonIntegralPointerType(LoadTy->getScalarType()))
+ // TODO: Can allow nullptrs from constant zeros
+ return -1;
+
unsigned AS = Src->getType()->getPointerAddressSpace();
// Otherwise, see if we can constant fold a load from the constant with the
// offset applied as appropriate.
Modified: llvm/trunk/test/Transforms/GVN/non-integral-pointers.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/GVN/non-integral-pointers.ll?rev=354403&r1=354402&r2=354403&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/GVN/non-integral-pointers.ll (original)
+++ llvm/trunk/test/Transforms/GVN/non-integral-pointers.ll Tue Feb 19 15:49:38 2019
@@ -154,3 +154,62 @@ define i8 addrspace(4)* @forward_store_z
%ref = load i8 addrspace(4)*, i8 addrspace(4)* addrspace(4)* %loc
ret i8 addrspace(4)* %ref
}
+
+ at NonZeroConstant = constant <4 x i64> <i64 3, i64 3, i64 3, i64 3>
+ at ZeroConstant = constant <4 x i64> zeroinitializer
+
+
+; Can't forward as the load might be dead. (Pretend we wrote out the alwaysfalse idiom above.)
+define i8 addrspace(4)* @neg_forward_memcopy(i8 addrspace(4)* addrspace(4)* %loc) {
+; CHECK-LABEL: @neg_forward_memcopy(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[LOC_BC:%.*]] = bitcast i8 addrspace(4)* addrspace(4)* [[LOC:%.*]] to i8 addrspace(4)*
+; CHECK-NEXT: call void @llvm.memcpy.p4i8.p0i8.i64(i8 addrspace(4)* align 4 [[LOC_BC]], i8* bitcast (<4 x i64>* @NonZeroConstant to i8*), i64 8, i1 false)
+; CHECK-NEXT: [[REF:%.*]] = load i8 addrspace(4)*, i8 addrspace(4)* addrspace(4)* [[LOC]]
+; CHECK-NEXT: ret i8 addrspace(4)* [[REF]]
+;
+entry:
+ %loc.bc = bitcast i8 addrspace(4)* addrspace(4)* %loc to i8 addrspace(4)*
+ %src.bc = bitcast <4 x i64>* @NonZeroConstant to i8*
+ call void @llvm.memcpy.p4i8.p0i8.i64(i8 addrspace(4)* align 4 %loc.bc, i8* %src.bc, i64 8, i1 false)
+ %ref = load i8 addrspace(4)*, i8 addrspace(4)* addrspace(4)* %loc
+ ret i8 addrspace(4)* %ref
+}
+
+define <1 x i8 addrspace(4)*> @neg_forward_memcpy_vload(<1 x i8 addrspace(4)*> addrspace(4)* %loc) {
+; CHECK-LABEL: @neg_forward_memcpy_vload(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[LOC_BC:%.*]] = bitcast <1 x i8 addrspace(4)*> addrspace(4)* [[LOC:%.*]] to i8 addrspace(4)*
+; CHECK-NEXT: call void @llvm.memcpy.p4i8.p0i8.i64(i8 addrspace(4)* align 4 [[LOC_BC]], i8* bitcast (<4 x i64>* @NonZeroConstant to i8*), i64 8, i1 false)
+; CHECK-NEXT: [[REF:%.*]] = load <1 x i8 addrspace(4)*>, <1 x i8 addrspace(4)*> addrspace(4)* [[LOC]]
+; CHECK-NEXT: ret <1 x i8 addrspace(4)*> [[REF]]
+;
+entry:
+ %loc.bc = bitcast <1 x i8 addrspace(4)*> addrspace(4)* %loc to i8 addrspace(4)*
+ %src.bc = bitcast <4 x i64>* @NonZeroConstant to i8*
+ call void @llvm.memcpy.p4i8.p0i8.i64(i8 addrspace(4)* align 4 %loc.bc, i8* %src.bc, i64 8, i1 false)
+ %ref = load <1 x i8 addrspace(4)*>, <1 x i8 addrspace(4)*> addrspace(4)* %loc
+ ret <1 x i8 addrspace(4)*> %ref
+}
+
+
+; Can forward since we can do so w/o breaking types
+; TODO: missed optimization
+define i8 addrspace(4)* @forward_memcpy_zero(i8 addrspace(4)* addrspace(4)* %loc) {
+; CHECK-LABEL: @forward_memcpy_zero(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[LOC_BC:%.*]] = bitcast i8 addrspace(4)* addrspace(4)* [[LOC:%.*]] to i8 addrspace(4)*
+; CHECK-NEXT: call void @llvm.memcpy.p4i8.p0i8.i64(i8 addrspace(4)* align 4 [[LOC_BC]], i8* bitcast (<4 x i64>* @ZeroConstant to i8*), i64 8, i1 false)
+; CHECK-NEXT: [[REF:%.*]] = load i8 addrspace(4)*, i8 addrspace(4)* addrspace(4)* [[LOC]]
+; CHECK-NEXT: ret i8 addrspace(4)* [[REF]]
+;
+entry:
+ %loc.bc = bitcast i8 addrspace(4)* addrspace(4)* %loc to i8 addrspace(4)*
+ %src.bc = bitcast <4 x i64>* @ZeroConstant to i8*
+ call void @llvm.memcpy.p4i8.p0i8.i64(i8 addrspace(4)* align 4 %loc.bc, i8* %src.bc, i64 8, i1 false)
+ %ref = load i8 addrspace(4)*, i8 addrspace(4)* addrspace(4)* %loc
+ ret i8 addrspace(4)* %ref
+}
+
+
+declare void @llvm.memcpy.p4i8.p0i8.i64(i8 addrspace(4)* nocapture, i8* nocapture, i64, i1) nounwind
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