llvm-project/llvm/test/Analysis/BasicAA/gep-alias.ll

; RUN: opt < %s -gvn -instcombine -S |& FileCheck %s
; Make sure that basicaa thinks R and r are must aliases.

target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"

define i32 @test1(i8 * %P) {
entry:
	%Q = bitcast i8* %P to {i32, i32}*
	%R = getelementptr {i32, i32}* %Q, i32 0, i32 1
	%S = load i32* %R

	%q = bitcast i8* %P to {i32, i32}*
	%r = getelementptr {i32, i32}* %q, i32 0, i32 1
	%s = load i32* %r

	%t = sub i32 %S, %s
	ret i32 %t
; CHECK: @test1
; CHECK: ret i32 0
}

define i32 @test2(i8 * %P) {
entry:
	%Q = bitcast i8* %P to {i32, i32, i32}*
	%R = getelementptr {i32, i32, i32}* %Q, i32 0, i32 1
	%S = load i32* %R

	%r = getelementptr {i32, i32, i32}* %Q, i32 0, i32 2
  store i32 42, i32* %r

	%s = load i32* %R

	%t = sub i32 %S, %s
	ret i32 %t
; CHECK: @test2
; CHECK: ret i32 0
}


; This was a miscompilation.
define i32 @test3({float, {i32, i32, i32}}* %P) {
entry:
  %P2 = getelementptr {float, {i32, i32, i32}}* %P, i32 0, i32 1
	%R = getelementptr {i32, i32, i32}* %P2, i32 0, i32 1
	%S = load i32* %R

	%r = getelementptr {i32, i32, i32}* %P2, i32 0, i32 2
  store i32 42, i32* %r

	%s = load i32* %R

	%t = sub i32 %S, %s
	ret i32 %t
; CHECK: @test3
; CHECK: ret i32 0
}


;; This is reduced from the SmallPtrSet constructor.
%SmallPtrSetImpl = type { i8**, i32, i32, i32, [1 x i8*] }
%SmallPtrSet64 = type { %SmallPtrSetImpl, [64 x i8*] }

define i32 @test4(%SmallPtrSet64* %P) {
entry:
  %tmp2 = getelementptr inbounds %SmallPtrSet64* %P, i64 0, i32 0, i32 1
  store i32 64, i32* %tmp2, align 8
  %tmp3 = getelementptr inbounds %SmallPtrSet64* %P, i64 0, i32 0, i32 4, i64 64
  store i8* null, i8** %tmp3, align 8
  %tmp4 = load i32* %tmp2, align 8
	ret i32 %tmp4
; CHECK: @test4
; CHECK: ret i32 64
}