llvm-6502/test/CodeGen/X86/shift-combine-crash.ll
Andrea Di Biagio d47cb57ab8 [DAG] Fix an assertion failure caused by an invalid cast in method 'BuildVectorSDNode::isConstantSplat'
This patch renames method 'isConstantSplat' as 'getConstantSplatValue'
(mainly for consistency reasons), and rewrites its logic to ensure
that we always perform a legal 'cast<ConstantSDNode>'.

Added test shift-combine-crash.ll to verify that DAGCombiner no longer crashes with an assertion failure in the attempt to simplify a vector shift by a vector of all undef counts.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204536 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-22 01:47:22 +00:00

58 lines
1.7 KiB
LLVM

; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mcpu=corei7 > /dev/null
; Verify that DAGCombiner doesn't crash with an assertion failure in the
; attempt to cast a ISD::UNDEF node to a ConstantSDNode.
; During type legalization, the vector shift operation in function @test1 is
; split into two legal shifts that work on <2 x i64> elements.
; The first shift of the legalized sequence would be a shift by all undefs.
; DAGCombiner will then try to simplify the vector shift and check if the
; vector of shift counts is a splat. Make sure that llc doesn't crash
; at that stage.
define <4 x i64> @test1(<4 x i64> %A) {
%shl = shl <4 x i64> %A, <i64 undef, i64 undef, i64 1, i64 2>
ret <4 x i64> %shl
}
; Also, verify that DAGCombiner doesn't crash when trying to combine shifts
; with different combinations of undef elements in the vector shift count.
define <4 x i64> @test2(<4 x i64> %A) {
%shl = shl <4 x i64> %A, <i64 2, i64 3, i64 undef, i64 undef>
ret <4 x i64> %shl
}
define <4 x i64> @test3(<4 x i64> %A) {
%shl = shl <4 x i64> %A, <i64 2, i64 undef, i64 3, i64 undef>
ret <4 x i64> %shl
}
define <4 x i64> @test4(<4 x i64> %A) {
%shl = shl <4 x i64> %A, <i64 undef, i64 2, i64 undef, i64 3>
ret <4 x i64> %shl
}
define <4 x i64> @test5(<4 x i64> %A) {
%shl = shl <4 x i64> %A, <i64 2, i64 undef, i64 undef, i64 undef>
ret <4 x i64> %shl
}
define <4 x i64> @test6(<4 x i64> %A) {
%shl = shl <4 x i64> %A, <i64 undef, i64 undef, i64 3, i64 undef>
ret <4 x i64> %shl
}
define <4 x i64> @test7(<4 x i64> %A) {
%shl = shl <4 x i64> %A, <i64 undef, i64 undef, i64 undef, i64 3>
ret <4 x i64> %shl
}
define <4 x i64> @test8(<4 x i64> %A) {
%shl = shl <4 x i64> %A, <i64 undef, i64 undef, i64 undef, i64 undef>
ret <4 x i64> %shl
}