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llvm-project/llvm/test/Transforms/MergeFunc/ptr-int-transitivity-1.ll

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PR17925 bugfix. Short description. This issue is about case of treating pointers as integers. We treat pointers as different if they references different address space. At the same time, we treat pointers equal to integers (with machine address width). It was a point of false-positive. Consider next case on 32bit machine: void foo0(i32 addrespace(1)* %p) void foo1(i32 addrespace(2)* %p) void foo2(i32 %p) foo0 != foo1, while foo1 == foo2 and foo0 == foo2. As you can see it breaks transitivity. That means that result depends on order of how functions are presented in module. Next order causes merging of foo0 and foo1: foo2, foo0, foo1 First foo0 will be merged with foo2, foo0 will be erased. Second foo1 will be merged with foo2. Depending on order, things could be merged we don't expect to. The fix: Forbid to treat any pointer as integer, except for those, who belong to address space 0. llvm-svn: 195769
2013-11-27 00:11:03 +08:00
; RUN: opt -S -mergefunc < %s | not grep "functions merged"
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
declare void @stuff()
define void @f0(i64 %p0) {
entry:
call void @stuff()
call void @stuff()
call void @stuff()
ret void
}
define void @f2(i64 addrspace(1)* %p0) {
entry:
call void @stuff()
call void @stuff()
call void @stuff()
ret void
}