[AArch64] Skip mask checks for masks with an odd number of elements.
Some checks in isShuffleMaskLegal expect an even number of elements,
e.g. isTRN_v_undef_Mask or isUZP_v_undef_Mask, otherwise they access
invalid elements and crash. This patch adds checks to the impacted
functions.
Fixes PR41951
Reviewers: t.p.northover, dmgreen, samparker
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D60690
llvm-svn: 361235
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index 43620f1..4b027e9 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -6292,6 +6292,8 @@
static bool isTRNMask(ArrayRef<int> M, EVT VT, unsigned &WhichResult) {
unsigned NumElts = VT.getVectorNumElements();
+ if (NumElts % 2 != 0)
+ return false;
WhichResult = (M[0] == 0 ? 0 : 1);
for (unsigned i = 0; i < NumElts; i += 2) {
if ((M[i] >= 0 && (unsigned)M[i] != i + WhichResult) ||
@@ -6306,6 +6308,8 @@
/// Mask is e.g., <0, 0, 1, 1> instead of <0, 4, 1, 5>.
static bool isZIP_v_undef_Mask(ArrayRef<int> M, EVT VT, unsigned &WhichResult) {
unsigned NumElts = VT.getVectorNumElements();
+ if (NumElts % 2 != 0)
+ return false;
WhichResult = (M[0] == 0 ? 0 : 1);
unsigned Idx = WhichResult * NumElts / 2;
for (unsigned i = 0; i != NumElts; i += 2) {
@@ -6342,6 +6346,8 @@
/// Mask is e.g., <0, 0, 2, 2> instead of <0, 4, 2, 6>.
static bool isTRN_v_undef_Mask(ArrayRef<int> M, EVT VT, unsigned &WhichResult) {
unsigned NumElts = VT.getVectorNumElements();
+ if (NumElts % 2 != 0)
+ return false;
WhichResult = (M[0] == 0 ? 0 : 1);
for (unsigned i = 0; i < NumElts; i += 2) {
if ((M[i] >= 0 && (unsigned)M[i] != i + WhichResult) ||