llvm-6502/test/Analysis/CFLAliasAnalysis/multilevel-combine.ll
Hal Finkel 6a075f530a [CFL-AA] Update for handling of globals and more tests
We used to return PartialAlias if *either* variable being queried interacted
with arguments or globals. AFAICT, we can change this to only returning
MayAlias iff *both* variables being queried interacted with arguments or
globals.

Also, adding some basic functionality tests: some basic IPA tests, checking
that we give conservative responses with arguments/globals thrown in the mix,
and ensuring that we trace values through stores and loads.

Note that saying that 'x' interacted with arguments or globals means that the
Attributes of the StratifiedSet that 'x' belongs to has any bits set.

Patch by George Burgess IV, thanks!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219122 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-06 14:42:56 +00:00

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723 B
LLVM

; This testcase ensures that CFL AA responds conservatively when we union
; groups of pointers together through ternary/conditional operations
; Derived from:
; void foo(bool c) {
; char a, b;
; char *m = c ? &a : &b;
; *m;
; }
;
; RUN: opt < %s -cfl-aa -aa-eval -print-may-aliases -disable-output 2>&1 | FileCheck %s
%T = type { i32, [10 x i8] }
; CHECK: Function: test
define void @test(i1 %C) {
; CHECK: 10 Total Alias Queries Performed
; CHECK: 4 no alias responses
%M = alloca %T*, align 8 ; NoAlias with %A, %B, %MS, %AP
%A = alloca %T, align 8
%B = alloca %T, align 8
%MS = select i1 %C, %T* %B, %T* %A
store %T* %MS, %T** %M
%AP = load %T** %M ; PartialAlias with %A, %B
ret void
}