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| ; RUN: opt < %s -basicaa -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(...)
|