llvm/test/Assembler/ConstantExprNoFold.ll
Dan Gohman d363ae5299 Fix ConstantFold's folding of icmp instructions to recognize that,
for example, a one-past-the-end pointer from one global variable may
be equal to the base pointer of another global variable.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173995 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31 00:01:45 +00:00

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1017 B
LLVM

; This test checks to make sure that constant exprs don't fold in some simple
; situations
; RUN: llvm-as < %s | llvm-dis | FileCheck %s
; Even give it a datalayout, to tempt folding as much as possible.
target datalayout = "p:32:32"
@A = global i64 0
@B = global i64 0
; Don't fold this. @A might really be allocated next to @B, in which case the
; icmp should return true. It's not valid to *dereference* in @B from a pointer
; based on @A, but icmp isn't a dereference.
; CHECK: @C = global i1 icmp eq (i64* getelementptr inbounds (i64* @A, i64 1), i64* @B)
@C = global i1 icmp eq (i64* getelementptr inbounds (i64* @A, i64 1), i64* @B)
; Don't fold this completely away either. In theory this could be simplified
; to only use a gep on one side of the icmp though.
; CHECK: @D = global i1 icmp eq (i64* getelementptr inbounds (i64* @A, i64 1), i64* getelementptr inbounds (i64* @B, i64 2))
@D = global i1 icmp eq (i64* getelementptr inbounds (i64* @A, i64 1), i64* getelementptr inbounds (i64* @B, i64 2))