e9f7fa83d5
The BITCAST handling in computeKnownBits() previously only worked for little endian. This patch reverses the iteration over elements for a big endian target which allows this to work in this case also. SystemZ test case. Review: Eli Friedman https://reviews.llvm.org/D44249 llvm-svn: 327764
30 lines
972 B
LLVM
30 lines
972 B
LLVM
; Test that DAGCombiner gets helped by getKnownBitsForTargetNode() when
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; BITCAST nodes are involved on a big-endian target.
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;
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; RUN: llc -mtriple=s390x-linux-gnu -mcpu=z13 < %s | FileCheck %s
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define void @fun() {
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entry:
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br label %lab0
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lab0:
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%phi = phi i64 [ %sel, %lab0 ], [ 0, %entry ]
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%add = add nuw nsw i64 %phi, 1
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%cmp = icmp eq i64 %add, undef
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%ins = insertelement <2 x i1> undef, i1 %cmp, i32 0
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%xor = xor <2 x i1> %ins, <i1 true, i1 true>
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%extr = extractelement <2 x i1> %xor, i32 0
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; The EXTRACT_VECTOR_ELT is done first into an i32, and then AND:ed with
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; 1. The AND is not actually necessary since the element contains a CC (i1)
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; value. Test that the BITCAST nodes in the DAG when computing KnownBits is
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; handled so that the AND is removed. If this succeeds, this results in a CHI
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; instead of TMLL.
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; CHECK-LABEL: # %bb.0:
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; CHECK: chi
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; CHECK-NOT: tmll
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; CHECK: j
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%sel = select i1 %extr, i64 %add, i64 0
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br label %lab0
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}
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