| ; RUN: opt < %s -basic-aa -gvn -S | FileCheck %s |
| |
| ; GVN should eliminate the fully redundant %9 GEP which |
| ; allows DEAD to be removed. This is PR3198. |
| |
| ; The %7 and %4 loads combine to make %DEAD unneeded. |
| 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" |
| target triple = "i386-apple-darwin7" |
| @H = common global [100 x i32] zeroinitializer, align 32 ; <[100 x i32]*> [#uses=3] |
| @G = common global i32 0 ; <i32*> [#uses=2] |
| |
| define i32 @test(i32 %i) nounwind { |
| entry: |
| %0 = tail call i32 (...) @foo() nounwind ; <i32> [#uses=1] |
| %1 = icmp eq i32 %0, 0 ; <i1> [#uses=1] |
| br i1 %1, label %bb1, label %bb |
| |
| bb: ; preds = %entry |
| %2 = tail call i32 (...) @bar() nounwind ; <i32> [#uses=0] |
| %3 = getelementptr [100 x i32], [100 x i32]* @H, i32 0, i32 %i ; <i32*> [#uses=1] |
| %4 = load i32, i32* %3, align 4 ; <i32> [#uses=1] |
| store i32 %4, i32* @G, align 4 |
| br label %bb3 |
| |
| bb1: ; preds = %entry |
| %5 = tail call i32 (...) @baz() nounwind ; <i32> [#uses=0] |
| %6 = getelementptr [100 x i32], [100 x i32]* @H, i32 0, i32 %i ; <i32*> [#uses=1] |
| %7 = load i32, i32* %6, align 4 ; <i32> [#uses=2] |
| store i32 %7, i32* @G, align 4 |
| %8 = icmp eq i32 %7, 0 ; <i1> [#uses=1] |
| br i1 %8, label %bb3, label %bb4 |
| |
| bb3: ; preds = %bb1, %bb |
| %9 = getelementptr [100 x i32], [100 x i32]* @H, i32 0, i32 %i ; <i32*> [#uses=1] |
| %DEAD = load i32, i32* %9, align 4 ; <i32> [#uses=1] |
| ; CHECK: %DEAD = phi i32 [ 0, %bb1 ], [ %4, %bb ] |
| ret i32 %DEAD |
| |
| bb4: ; preds = %bb1 |
| ret i32 0 |
| } |
| |
| declare i32 @foo(...) |
| |
| declare i32 @bar(...) |
| |
| declare i32 @baz(...) |