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      1 ; Test that LICM uses basicaa to do alias analysis, which is capable of 
      2 ; disambiguating some obvious cases.  If LICM is able to disambiguate the
      3 ; two pointers, then the load should be hoisted, and the store sunk.
      4 
      5 ; RUN: opt < %s -basicaa -licm -S | FileCheck %s
      6 target datalayout = "E-p:64:64:64-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128"
      7 
      8 @A = global i32 7               ; <i32*> [#uses=3]
      9 @B = global i32 8               ; <i32*> [#uses=2]
     10 @C = global [2 x i32] [ i32 4, i32 8 ]          ; <[2 x i32]*> [#uses=2]
     11 
     12 define i32 @test1(i1 %c) {
     13         %Atmp = load i32, i32* @A            ; <i32> [#uses=2]
     14         br label %Loop
     15 
     16 Loop:           ; preds = %Loop, %0
     17         %ToRemove = load i32, i32* @A                ; <i32> [#uses=1]
     18         store i32 %Atmp, i32* @B
     19         br i1 %c, label %Out, label %Loop
     20 
     21 Out:            ; preds = %Loop
     22         %X = sub i32 %ToRemove, %Atmp           ; <i32> [#uses=1]
     23         ret i32 %X
     24         
     25 ; The Loop block should be empty after the load/store are promoted.
     26 ; CHECK:     @test1
     27 ; CHECK:        load i32, i32* @A
     28 ; CHECK:      Loop:
     29 ; CHECK-NEXT:   br i1 %c, label %Out, label %Loop
     30 ; CHECK:      Out:
     31 ; CHECK:        store i32 %Atmp, i32* @B
     32 }
     33 
     34 define i32 @test2(i1 %c) {
     35         br label %Loop
     36 
     37 Loop:           ; preds = %Loop, %0
     38         %AVal = load i32, i32* @A            ; <i32> [#uses=2]
     39         %C0 = getelementptr [2 x i32], [2 x i32]* @C, i64 0, i64 0         ; <i32*> [#uses=1]
     40         store i32 %AVal, i32* %C0
     41         %BVal = load i32, i32* @B            ; <i32> [#uses=2]
     42         %C1 = getelementptr [2 x i32], [2 x i32]* @C, i64 0, i64 1         ; <i32*> [#uses=1]
     43         store i32 %BVal, i32* %C1
     44         br i1 %c, label %Out, label %Loop
     45 
     46 Out:            ; preds = %Loop
     47         %X = sub i32 %AVal, %BVal               ; <i32> [#uses=1]
     48         ret i32 %X
     49 ; The Loop block should be empty after the load/store are promoted.
     50 ; CHECK:     @test2
     51 ; CHECK:      Loop:
     52 ; CHECK-NEXT:   br i1 %c, label %Out, label %Loop
     53 }
     54 
     55