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; RUN: opt -passes=newgvn -S < %s | FileCheck %s
define i32 @f1(i32 %x) {
; CHECK-LABEL: define i32 @f1(
bb0:
%cmp = icmp eq i32 %x, 0
br i1 %cmp, label %bb2, label %bb1
bb1:
br label %bb2
bb2:
%cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
%foo = add i32 %cond, %x
ret i32 %foo
; CHECK: bb2:
; CHECK: ret i32 %x
}
define i32 @f2(i32 %x) {
; CHECK-LABEL: define i32 @f2(
bb0:
%cmp = icmp ne i32 %x, 0
br i1 %cmp, label %bb1, label %bb2
bb1:
br label %bb2
bb2:
%cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
%foo = add i32 %cond, %x
ret i32 %foo
; CHECK: bb2:
; CHECK: ret i32 %x
}
define i32 @f3(i32 %x) {
; CHECK-LABEL: define i32 @f3(
bb0:
switch i32 %x, label %bb1 [ i32 0, label %bb2]
bb1:
br label %bb2
bb2:
%cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
%foo = add i32 %cond, %x
ret i32 %foo
; CHECK: bb2:
; CHECK: ret i32 %x
}
declare void @g(i1)
define void @f4(ptr %x) {
; CHECK-LABEL: define void @f4(
bb0:
%y = icmp eq ptr null, %x
br i1 %y, label %bb2, label %bb1
bb1:
br label %bb2
bb2:
%zed = icmp eq ptr null, %x
call void @g(i1 %zed)
; CHECK: call void @g(i1 %y)
ret void
}
define double @fcmp_oeq_not_zero(double %x, double %y) {
entry:
%cmp = fcmp oeq double %y, 2.0
br i1 %cmp, label %if, label %return
if:
%div = fdiv double %x, %y
br label %return
return:
%retval = phi double [ %div, %if ], [ %x, %entry ]
ret double %retval
; CHECK-LABEL: define double @fcmp_oeq_not_zero(
; CHECK: %div = fdiv double %x, 2.0
}
define double @fcmp_une_not_zero(double %x, double %y) {
entry:
%cmp = fcmp une double %y, 2.0
br i1 %cmp, label %return, label %else
else:
%div = fdiv double %x, %y
br label %return
return:
%retval = phi double [ %div, %else ], [ %x, %entry ]
ret double %retval
; CHECK-LABEL: define double @fcmp_une_not_zero(
; CHECK: %div = fdiv double %x, 2.0
}
; PR22376 - We can't propagate zero constants because -0.0
; compares equal to 0.0. If %y is -0.0 in this test case,
; we would produce the wrong sign on the infinity return value.
define double @fcmp_oeq_zero(double %x, double %y) {
entry:
%cmp = fcmp oeq double %y, 0.0
br i1 %cmp, label %if, label %return
if:
%div = fdiv double %x, %y
br label %return
return:
%retval = phi double [ %div, %if ], [ %x, %entry ]
ret double %retval
; CHECK-LABEL: define double @fcmp_oeq_zero(
; CHECK: %div = fdiv double %x, %y
}
define double @fcmp_une_zero(double %x, double %y) {
entry:
%cmp = fcmp une double %y, -0.0
br i1 %cmp, label %return, label %else
else:
%div = fdiv double %x, %y
br label %return
return:
%retval = phi double [ %div, %else ], [ %x, %entry ]
ret double %retval
; CHECK-LABEL: define double @fcmp_une_zero(
; CHECK: %div = fdiv double %x, %y
}
; We also cannot propagate a value if it's not a constant.
; This is because the value could be 0.0 or -0.0.
define double @fcmp_oeq_maybe_zero(double %x, double %y, double %z1, double %z2) {
entry:
%z = fadd double %z1, %z2
%cmp = fcmp oeq double %y, %z
br i1 %cmp, label %if, label %return
if:
%div = fdiv double %x, %z
br label %return
return:
%retval = phi double [ %div, %if ], [ %x, %entry ]
ret double %retval
; CHECK-LABEL: define double @fcmp_oeq_maybe_zero(
; CHECK: %div = fdiv double %x, %z
}
define double @fcmp_une_maybe_zero(double %x, double %y, double %z1, double %z2) {
entry:
%z = fadd double %z1, %z2
%cmp = fcmp une double %y, %z
br i1 %cmp, label %return, label %else
else:
%div = fdiv double %x, %z
br label %return
return:
%retval = phi double [ %div, %else ], [ %x, %entry ]
ret double %retval
; CHECK-LABEL: define double @fcmp_une_maybe_zero(
; CHECK: %div = fdiv double %x, %z
}
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