llvm-6502/test/Transforms/GVN/condprop.ll
Duncan Sands 190e5a3314 Nick pointed out on IRC that GVN's propagateEquality wasn't propagating
equalities into phi node operands for which the equality is known to
hold in the incoming basic block.  That's because replaceAllDominatedUsesWith
wasn't handling phi nodes correctly in general (that this didn't give wrong
results was just luck: the specific way GVN uses replaceAllDominatedUsesWith
precluded wrong changes to phi nodes).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152006 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-04 13:25:19 +00:00

252 lines
4.5 KiB
LLVM

; RUN: opt < %s -basicaa -gvn -S | FileCheck %s
@a = external global i32 ; <i32*> [#uses=7]
; CHECK: @test1
define i32 @test1() nounwind {
entry:
%0 = load i32* @a, align 4
%1 = icmp eq i32 %0, 4
br i1 %1, label %bb, label %bb1
bb: ; preds = %entry
br label %bb8
bb1: ; preds = %entry
%2 = load i32* @a, align 4
%3 = icmp eq i32 %2, 5
br i1 %3, label %bb2, label %bb3
bb2: ; preds = %bb1
br label %bb8
bb3: ; preds = %bb1
%4 = load i32* @a, align 4
%5 = icmp eq i32 %4, 4
; CHECK: br i1 false, label %bb4, label %bb5
br i1 %5, label %bb4, label %bb5
bb4: ; preds = %bb3
%6 = load i32* @a, align 4
%7 = add i32 %6, 5
br label %bb8
bb5: ; preds = %bb3
%8 = load i32* @a, align 4
%9 = icmp eq i32 %8, 5
; CHECK: br i1 false, label %bb6, label %bb7
br i1 %9, label %bb6, label %bb7
bb6: ; preds = %bb5
%10 = load i32* @a, align 4
%11 = add i32 %10, 4
br label %bb8
bb7: ; preds = %bb5
%12 = load i32* @a, align 4
br label %bb8
bb8: ; preds = %bb7, %bb6, %bb4, %bb2, %bb
%.0 = phi i32 [ %12, %bb7 ], [ %11, %bb6 ], [ %7, %bb4 ], [ 4, %bb2 ], [ 5, %bb ]
br label %return
return: ; preds = %bb8
ret i32 %.0
}
declare void @foo(i1)
declare void @bar(i32)
; CHECK: @test3
define void @test3(i32 %x, i32 %y) {
%xz = icmp eq i32 %x, 0
%yz = icmp eq i32 %y, 0
%z = and i1 %xz, %yz
br i1 %z, label %both_zero, label %nope
both_zero:
call void @foo(i1 %xz)
; CHECK: call void @foo(i1 true)
call void @foo(i1 %yz)
; CHECK: call void @foo(i1 true)
call void @bar(i32 %x)
; CHECK: call void @bar(i32 0)
call void @bar(i32 %y)
; CHECK: call void @bar(i32 0)
ret void
nope:
call void @foo(i1 %z)
; CHECK: call void @foo(i1 false)
ret void
}
; CHECK: @test4
define void @test4(i1 %b, i32 %x) {
br i1 %b, label %sw, label %case3
sw:
switch i32 %x, label %default [
i32 0, label %case0
i32 1, label %case1
i32 2, label %case0
i32 3, label %case3
i32 4, label %default
]
default:
; CHECK: default:
call void @bar(i32 %x)
; CHECK: call void @bar(i32 %x)
ret void
case0:
; CHECK: case0:
call void @bar(i32 %x)
; CHECK: call void @bar(i32 %x)
ret void
case1:
; CHECK: case1:
call void @bar(i32 %x)
; CHECK: call void @bar(i32 1)
ret void
case3:
; CHECK: case3:
call void @bar(i32 %x)
; CHECK: call void @bar(i32 %x)
ret void
}
; CHECK: @test5
define i1 @test5(i32 %x, i32 %y) {
%cmp = icmp eq i32 %x, %y
br i1 %cmp, label %same, label %different
same:
%cmp2 = icmp ne i32 %x, %y
; CHECK: ret i1 false
ret i1 %cmp2
different:
%cmp3 = icmp eq i32 %x, %y
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK: @test6
define i1 @test6(i32 %x, i32 %y) {
%cmp2 = icmp ne i32 %x, %y
%cmp = icmp eq i32 %x, %y
%cmp3 = icmp eq i32 %x, %y
br i1 %cmp, label %same, label %different
same:
; CHECK: ret i1 false
ret i1 %cmp2
different:
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK: @test7
define i1 @test7(i32 %x, i32 %y) {
%cmp = icmp sgt i32 %x, %y
br i1 %cmp, label %same, label %different
same:
%cmp2 = icmp sle i32 %x, %y
; CHECK: ret i1 false
ret i1 %cmp2
different:
%cmp3 = icmp sgt i32 %x, %y
; CHECK: ret i1 false
ret i1 %cmp3
}
; CHECK: @test8
define i1 @test8(i32 %x, i32 %y) {
%cmp2 = icmp sle i32 %x, %y
%cmp = icmp sgt i32 %x, %y
%cmp3 = icmp sgt i32 %x, %y
br i1 %cmp, label %same, label %different
same:
; CHECK: ret i1 false
ret i1 %cmp2
different:
; CHECK: ret i1 false
ret i1 %cmp3
}
; PR1768
; CHECK: @test9
define i32 @test9(i32 %i, i32 %j) {
%cmp = icmp eq i32 %i, %j
br i1 %cmp, label %cond_true, label %ret
cond_true:
%diff = sub i32 %i, %j
ret i32 %diff
; CHECK: ret i32 0
ret:
ret i32 5
; CHECK: ret i32 5
}
; PR1768
; CHECK: @test10
define i32 @test10(i32 %j, i32 %i) {
%cmp = icmp eq i32 %i, %j
br i1 %cmp, label %cond_true, label %ret
cond_true:
%diff = sub i32 %i, %j
ret i32 %diff
; CHECK: ret i32 0
ret:
ret i32 5
; CHECK: ret i32 5
}
declare i32 @yogibar()
; CHECK: @test11
define i32 @test11(i32 %x) {
%v0 = call i32 @yogibar()
%v1 = call i32 @yogibar()
%cmp = icmp eq i32 %v0, %v1
br i1 %cmp, label %cond_true, label %next
cond_true:
ret i32 %v1
; CHECK: ret i32 %v0
next:
%cmp2 = icmp eq i32 %x, %v0
br i1 %cmp2, label %cond_true2, label %next2
cond_true2:
ret i32 %v0
; CHECK: ret i32 %x
next2:
ret i32 0
}
; CHECK: @test12
define i32 @test12(i32 %x) {
%cmp = icmp eq i32 %x, 0
br i1 %cmp, label %cond_true, label %cond_false
cond_true:
br label %ret
cond_false:
br label %ret
ret:
%res = phi i32 [ %x, %cond_true ], [ %x, %cond_false ]
; CHECK: %res = phi i32 [ 0, %cond_true ], [ %x, %cond_false ]
ret i32 %res
}