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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=ipsccp -S | FileCheck %s
declare void @use(i1)
; We can simplify the conditions in the true block, because the condition
; allows us to replace all uses of %a in the block with a constant.
define void @val_undef_eq() {
; CHECK-LABEL: @val_undef_eq(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A:%.*]] = add nuw nsw i32 undef, 0
; CHECK-NEXT: [[BC_1:%.*]] = icmp eq i32 [[A]], 10
; CHECK-NEXT: br i1 [[BC_1]], label [[TRUE:%.*]], label [[FALSE:%.*]]
; CHECK: true:
; CHECK-NEXT: call void @use(i1 false)
; CHECK-NEXT: call void @use(i1 true)
; CHECK-NEXT: ret void
; CHECK: false:
; CHECK-NEXT: ret void
;
entry:
%a = add i32 undef, 0
%bc.1 = icmp eq i32 %a, 10
br i1 %bc.1, label %true, label %false
true:
%f.1 = icmp ne i32 %a, 10
call void @use(i1 %f.1)
%f.2 = icmp eq i32 %a, 10
call void @use(i1 %f.2)
ret void
false:
ret void
}
declare void @use.i32(i32)
; It is not allowed to use the range information from the condition to remove
; %a.127 = and ... in the true block, as %a could be undef.
define void @val_undef_range() {
; CHECK-LABEL: @val_undef_range(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A:%.*]] = add nuw nsw i32 undef, 0
; CHECK-NEXT: [[BC_1:%.*]] = icmp ult i32 [[A]], 127
; CHECK-NEXT: br i1 [[BC_1]], label [[TRUE:%.*]], label [[FALSE:%.*]]
; CHECK: true:
; CHECK-NEXT: call void @use(i1 false)
; CHECK-NEXT: [[A_127:%.*]] = and i32 [[A]], 127
; CHECK-NEXT: call void @use.i32(i32 [[A_127]])
; CHECK-NEXT: ret void
; CHECK: false:
; CHECK-NEXT: ret void
;
entry:
%a = add i32 undef, 0
%bc.1 = icmp ult i32 %a, 127
br i1 %bc.1, label %true, label %false
true:
%f.1 = icmp eq i32 %a, 128
call void @use(i1 %f.1)
%a.127 = and i32 %a, 127
call void @use.i32(i32 %a.127)
ret void
false:
ret void
}
; All uses of %p can be replaced by a constant (10).
define void @val_singlecrfromundef_range(i1 %cond) {
; CHECK-LABEL: @val_singlecrfromundef_range(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[COND:%.*]], label [[INC1:%.*]], label [[INC2:%.*]]
; CHECK: inc1:
; CHECK-NEXT: br label [[IF:%.*]]
; CHECK: inc2:
; CHECK-NEXT: br label [[IF]]
; CHECK: if:
; CHECK-NEXT: br label [[TRUE:%.*]]
; CHECK: true:
; CHECK-NEXT: call void @use(i1 false)
; CHECK-NEXT: [[P_127:%.*]] = and i32 10, 127
; CHECK-NEXT: call void @use.i32(i32 [[P_127]])
; CHECK-NEXT: ret void
;
entry:
br i1 %cond, label %inc1, label %inc2
inc1:
br label %if
inc2:
br label %if
if:
%p = phi i32 [ 10, %inc1 ], [ undef, %inc2 ]
%bc.1 = icmp ult i32 %p, 127
br i1 %bc.1, label %true, label %false
true:
%f.1 = icmp eq i32 %p, 128
call void @use(i1 %f.1)
%p.127 = and i32 %p, 127
call void @use.i32(i32 %p.127)
ret void
false:
ret void
}
; It is not allowed to use the information from the condition ([0, 128))
; to remove a.127.2 = and i32 %p, 127, as %p might be undef.
define void @val_undef_to_cr_to_overdef_range(i32 %a, i1 %cond) {
; CHECK-LABEL: @val_undef_to_cr_to_overdef_range(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A_127:%.*]] = and i32 [[A:%.*]], 127
; CHECK-NEXT: br i1 [[COND:%.*]], label [[INC1:%.*]], label [[INC2:%.*]]
; CHECK: inc1:
; CHECK-NEXT: br label [[IF:%.*]]
; CHECK: inc2:
; CHECK-NEXT: br label [[IF]]
; CHECK: if:
; CHECK-NEXT: [[P:%.*]] = phi i32 [ [[A_127]], [[INC1]] ], [ undef, [[INC2]] ]
; CHECK-NEXT: [[BC_1:%.*]] = icmp ult i32 [[P]], 100
; CHECK-NEXT: br i1 [[BC_1]], label [[TRUE:%.*]], label [[FALSE:%.*]]
; CHECK: true:
; CHECK-NEXT: call void @use(i1 false)
; CHECK-NEXT: [[P_127:%.*]] = and i32 [[P]], 127
; CHECK-NEXT: call void @use.i32(i32 [[P_127]])
; CHECK-NEXT: ret void
; CHECK: false:
; CHECK-NEXT: ret void
;
entry:
%a.127 = and i32 %a, 127
br i1 %cond, label %inc1, label %inc2
inc1:
br label %if
inc2:
br label %if
if:
%p = phi i32 [ %a.127, %inc1 ], [ undef, %inc2 ]
%bc.1 = icmp ult i32 %p, 100
br i1 %bc.1, label %true, label %false
true:
%f.1 = icmp eq i32 %p, 128
call void @use(i1 %f.1)
%p.127 = and i32 %p, 127
call void @use.i32(i32 %p.127)
ret void
false:
ret void
}
; All uses of %p can be replaced by a constant (10), we are allowed to use it
; as a bound too.
define void @bound_singlecrfromundef(i32 %a, i1 %cond) {
; CHECK-LABEL: @bound_singlecrfromundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[COND:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: br label [[PRED:%.*]]
; CHECK: bb2:
; CHECK-NEXT: br label [[PRED]]
; CHECK: pred:
; CHECK-NEXT: [[BC_1:%.*]] = icmp ugt i32 [[A:%.*]], 10
; CHECK-NEXT: br i1 [[BC_1]], label [[TRUE:%.*]], label [[FALSE:%.*]]
; CHECK: true:
; CHECK-NEXT: call void @use(i1 false)
; CHECK-NEXT: call void @use(i1 true)
; CHECK-NEXT: [[A_127:%.*]] = and i32 [[A]], 127
; CHECK-NEXT: call void @use.i32(i32 [[A_127]])
; CHECK-NEXT: ret void
; CHECK: false:
; CHECK-NEXT: ret void
;
entry:
br i1 %cond, label %bb1, label %bb2
bb1:
br label %pred
bb2:
br label %pred
pred:
%p = phi i32 [ undef, %bb1 ], [ 10, %bb2 ]
%bc.1 = icmp ugt i32 %a, %p
br i1 %bc.1, label %true, label %false
true:
%f.1 = icmp eq i32 %a, 5
call void @use(i1 %f.1)
%t.1 = icmp ne i32 %a, 5
call void @use(i1 %t.1)
%a.127 = and i32 %a, 127
call void @use.i32(i32 %a.127)
ret void
false:
ret void
}
; It is not allowed to use the information from %p as a bound, because an
; incoming value is undef.
define void @bound_range_and_undef(i32 %a, i1 %cond) {
; CHECK-LABEL: @bound_range_and_undef(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A_10:%.*]] = and i32 [[A:%.*]], 127
; CHECK-NEXT: br i1 [[COND:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: br label [[PRED:%.*]]
; CHECK: bb2:
; CHECK-NEXT: br label [[PRED]]
; CHECK: pred:
; CHECK-NEXT: [[P:%.*]] = phi i32 [ [[A_10]], [[BB1]] ], [ undef, [[BB2]] ]
; CHECK-NEXT: [[BC_1:%.*]] = icmp ugt i32 [[A]], [[P]]
; CHECK-NEXT: br i1 [[BC_1]], label [[TRUE:%.*]], label [[FALSE:%.*]]
; CHECK: true:
; CHECK-NEXT: [[F_1:%.*]] = icmp eq i32 [[A]], 300
; CHECK-NEXT: call void @use(i1 [[F_1]])
; CHECK-NEXT: [[A_127_2:%.*]] = and i32 [[P]], 127
; CHECK-NEXT: call void @use.i32(i32 [[A_127_2]])
; CHECK-NEXT: ret void
; CHECK: false:
; CHECK-NEXT: ret void
;
entry:
%a.10 = and i32 %a, 127
br i1 %cond, label %bb1, label %bb2
bb1:
br label %pred
bb2:
br label %pred
pred:
%p = phi i32 [ %a.10, %bb1 ], [ undef, %bb2 ]
%bc.1 = icmp ugt i32 %a, %p
br i1 %bc.1, label %true, label %false
true:
%f.1 = icmp eq i32 %a, 300
call void @use(i1 %f.1)
%a.127.2 = and i32 %p, 127
call void @use.i32(i32 %a.127.2)
ret void
false:
ret void
}
|
