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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
define i32 @fold(i32 %x) {
; CHECK-LABEL: @fold(
; CHECK-NEXT: [[Y:%.*]] = freeze i32 [[X:%.*]]
; CHECK-NEXT: ret i32 [[Y]]
;
%y = freeze i32 %x
%z = freeze i32 %y
ret i32 %z
}
define i32 @make_const() {
; CHECK-LABEL: @make_const(
; CHECK-NEXT: ret i32 10
;
%x = freeze i32 10
ret i32 %x
}
define i32 @and_freeze_undef(i32 %x) {
; CHECK-LABEL: @and_freeze_undef(
; CHECK-NEXT: ret i32 0
;
%f = freeze i32 undef
%res = and i32 %x, %f
ret i32 %res
}
declare void @use_i32(i32)
define i32 @and_freeze_undef_multipleuses(i32 %x) {
; CHECK-LABEL: @and_freeze_undef_multipleuses(
; CHECK-NEXT: call void @use_i32(i32 0)
; CHECK-NEXT: ret i32 0
;
%f = freeze i32 undef
%res = and i32 %x, %f
call void @use_i32(i32 %f)
ret i32 %res
}
define i32 @or_freeze_undef(i32 %x) {
; CHECK-LABEL: @or_freeze_undef(
; CHECK-NEXT: ret i32 -1
;
%f = freeze i32 undef
%res = or i32 %x, %f
ret i32 %res
}
define i32 @or_freeze_undef_multipleuses(i32 %x) {
; CHECK-LABEL: @or_freeze_undef_multipleuses(
; CHECK-NEXT: call void @use_i32(i32 0)
; CHECK-NEXT: ret i32 [[X:%.*]]
;
%f = freeze i32 undef
%res = or i32 %x, %f
call void @use_i32(i32 %f)
ret i32 %res
}
declare void @use_i32_i1(i32, i1)
define void @or_select_multipleuses(i32 %x, i1 %y) {
; CHECK-LABEL: @or_select_multipleuses(
; CHECK-NEXT: call void @use_i32_i1(i32 32, i1 [[Y:%.*]])
; CHECK-NEXT: ret void
;
%f = freeze i1 undef
%a = select i1 %f, i32 %x, i32 32 ; prefers %f to be false
%b = or i1 %f, %y ; prefers %f to be true
call void @use_i32_i1(i32 %a, i1 %b)
ret void
}
define void @or_select_multipleuses_logical(i32 %x, i1 %y) {
; CHECK-LABEL: @or_select_multipleuses_logical(
; CHECK-NEXT: call void @use_i32_i1(i32 32, i1 [[Y:%.*]])
; CHECK-NEXT: ret void
;
%f = freeze i1 undef
%a = select i1 %f, i32 %x, i32 32 ; prefers %f to be false
%b = select i1 %f, i1 true, i1 %y ; prefers %f to be true
call void @use_i32_i1(i32 %a, i1 %b)
ret void
}
; Move the freeze forward to prevent poison from spreading.
define i32 @early_freeze_test1(i32 %x, i32 %y) {
; CHECK-LABEL: @early_freeze_test1(
; CHECK-NEXT: [[V1:%.*]] = add i32 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[V1_FR:%.*]] = freeze i32 [[V1]]
; CHECK-NEXT: [[V2:%.*]] = shl i32 [[V1_FR]], 1
; CHECK-NEXT: [[V3:%.*]] = and i32 [[V2]], 2
; CHECK-NEXT: ret i32 [[V3]]
;
%v1 = add i32 %x, %y
%v2 = shl i32 %v1, 1
%v3 = and i32 %v2, 2
%v3.fr = freeze i32 %v3
ret i32 %v3.fr
}
define i1 @early_freeze_test2(i32* %ptr) {
; CHECK-LABEL: @early_freeze_test2(
; CHECK-NEXT: [[V1:%.*]] = load i32, i32* [[PTR:%.*]], align 4
; CHECK-NEXT: [[V1_FR:%.*]] = freeze i32 [[V1]]
; CHECK-NEXT: [[V2:%.*]] = and i32 [[V1_FR]], 1
; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[V2]], 0
; CHECK-NEXT: ret i1 [[COND]]
;
%v1 = load i32, i32* %ptr
%v2 = and i32 %v1, 1
%cond = icmp eq i32 %v2, 0
%cond.fr = freeze i1 %cond
ret i1 %cond.fr
}
; add can overflows, so we cannot move freeze beyond add
define i32 @early_freeze_test3(i32 %v1) {
; CHECK-LABEL: @early_freeze_test3(
; CHECK-NEXT: [[V2:%.*]] = shl i32 [[V1:%.*]], 1
; CHECK-NEXT: [[V3:%.*]] = add nuw i32 [[V2]], 2
; CHECK-NEXT: [[V3_FR:%.*]] = freeze i32 [[V3]]
; CHECK-NEXT: [[V4:%.*]] = or i32 [[V3_FR]], 1
; CHECK-NEXT: ret i32 [[V4]]
;
%v2 = shl i32 %v1, 1
%v3 = add nuw i32 %v2, 2
%v4 = or i32 %v3, 1
%v4.fr = freeze i32 %v4
ret i32 %v4.fr
}
; If replace all dominated uses of v to freeze(v).
define void @freeze_dominated_uses_test1(i32 %v) {
; CHECK-LABEL: @freeze_dominated_uses_test1(
; CHECK-NEXT: [[V_FR:%.*]] = freeze i32 [[V:%.*]]
; CHECK-NEXT: call void @use_i32(i32 [[V_FR]])
; CHECK-NEXT: call void @use_i32(i32 [[V_FR]])
; CHECK-NEXT: ret void
;
%v.fr = freeze i32 %v
call void @use_i32(i32 %v)
call void @use_i32(i32 %v.fr)
ret void
}
define void @freeze_dominated_uses_test2(i32 %v) {
; CHECK-LABEL: @freeze_dominated_uses_test2(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @use_i32(i32 [[V:%.*]])
; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[V]], 0
; CHECK-NEXT: br i1 [[COND]], label [[BB0:%.*]], label [[BB1:%.*]]
; CHECK: bb0:
; CHECK-NEXT: [[V_FR:%.*]] = freeze i32 [[V]]
; CHECK-NEXT: call void @use_i32(i32 [[V_FR]])
; CHECK-NEXT: call void @use_i32(i32 [[V_FR]])
; CHECK-NEXT: br label [[END:%.*]]
; CHECK: bb1:
; CHECK-NEXT: call void @use_i32(i32 [[V]])
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: ret void
;
entry:
call void @use_i32(i32 %v)
%cond = icmp eq i32 %v, 0
br i1 %cond, label %bb0, label %bb1
bb0:
%v.fr = freeze i32 %v
call void @use_i32(i32 %v.fr)
call void @use_i32(i32 %v)
br label %end
bb1:
call void @use_i32(i32 %v)
br label %end
end:
ret void
}
; If there is a duplicate freeze, it will be removed.
define void @freeze_dominated_uses_test3(i32 %v, i1 %cond) {
; CHECK-LABEL: @freeze_dominated_uses_test3(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[V_FR1:%.*]] = freeze i32 [[V:%.*]]
; CHECK-NEXT: call void @use_i32(i32 [[V_FR1]])
; CHECK-NEXT: br i1 [[COND:%.*]], label [[BB0:%.*]], label [[BB1:%.*]]
; CHECK: bb0:
; CHECK-NEXT: call void @use_i32(i32 [[V_FR1]])
; CHECK-NEXT: br label [[END:%.*]]
; CHECK: bb1:
; CHECK-NEXT: call void @use_i32(i32 [[V_FR1]])
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: ret void
;
entry:
%v.fr1 = freeze i32 %v
call void @use_i32(i32 %v.fr1)
br i1 %cond, label %bb0, label %bb1
bb0:
%v.fr2 = freeze i32 %v
call void @use_i32(i32 %v.fr2)
br label %end
bb1:
call void @use_i32(i32 %v)
br label %end
end:
ret void
}
|
