llvm-6502/test/Transforms/JumpThreading/thread-loads.ll
Chris Lattner 5161de6ebb enhance jump threading to preserve TBAA information when PRE'ing loads,
fixing rdar://11039258, an issue that came up when inspecting clang's 
bootstrapped codegen.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152635 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-13 18:07:41 +00:00

82 lines
2.1 KiB
LLVM

; RUN: opt < %s -jump-threading -S | FileCheck %s
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"
; Test that we can thread through the block with the partially redundant load (%2).
; rdar://6402033
define i32 @test1(i32* %P) nounwind {
; CHECK: @test1
entry:
%0 = tail call i32 (...)* @f1() nounwind ; <i32> [#uses=1]
%1 = icmp eq i32 %0, 0 ; <i1> [#uses=1]
br i1 %1, label %bb1, label %bb
bb: ; preds = %entry
; CHECK: bb1.thread:
; CHECK: store
; CHECK: br label %bb3
store i32 42, i32* %P, align 4
br label %bb1
bb1: ; preds = %entry, %bb
%res.0 = phi i32 [ 1, %bb ], [ 0, %entry ] ; <i32> [#uses=2]
%2 = load i32* %P, align 4 ; <i32> [#uses=1]
%3 = icmp sgt i32 %2, 36 ; <i1> [#uses=1]
br i1 %3, label %bb3, label %bb2
bb2: ; preds = %bb1
%4 = tail call i32 (...)* @f2() nounwind ; <i32> [#uses=0]
ret i32 %res.0
bb3: ; preds = %bb1
; CHECK: bb3:
; CHECK: %res.01 = phi i32 [ 1, %bb1.thread ], [ 0, %bb1 ]
; CHECK: ret i32 %res.01
ret i32 %res.0
}
declare i32 @f1(...)
declare i32 @f2(...)
;; Check that we preserve TBAA information.
; rdar://11039258
define i32 @test2(i32* %P) nounwind {
; CHECK: @test2
entry:
%0 = tail call i32 (...)* @f1() nounwind ; <i32> [#uses=1]
%1 = icmp eq i32 %0, 0 ; <i1> [#uses=1]
br i1 %1, label %bb1, label %bb
bb: ; preds = %entry
; CHECK: bb1.thread:
; CHECK: store{{.*}}, !tbaa !0
; CHECK: br label %bb3
store i32 42, i32* %P, align 4, !tbaa !0
br label %bb1
bb1: ; preds = %entry, %bb
%res.0 = phi i32 [ 1, %bb ], [ 0, %entry ]
%2 = load i32* %P, align 4, !tbaa !0
%3 = icmp sgt i32 %2, 36
br i1 %3, label %bb3, label %bb2
bb2: ; preds = %bb1
%4 = tail call i32 (...)* @f2() nounwind
ret i32 %res.0
bb3: ; preds = %bb1
; CHECK: bb3:
; CHECK: %res.01 = phi i32 [ 1, %bb1.thread ], [ 0, %bb1 ]
; CHECK: ret i32 %res.01
ret i32 %res.0
}
!0 = metadata !{metadata !"int", metadata !1}
!1 = metadata !{metadata !"omnipotent char", metadata !2}
!2 = metadata !{metadata !"Simple C/C++ TBAA", null}