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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -switch-range-to-icmp -S | FileCheck %s
declare i32 @f(i32)
define i32 @basic(i32 %x) {
; CHECK-LABEL: @basic(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X_OFF:%.*]] = add i32 [[X:%.*]], -5
; CHECK-NEXT: [[SWITCH:%.*]] = icmp ult i32 [[X_OFF]], 3
; CHECK-NEXT: br i1 [[SWITCH]], label [[A:%.*]], label [[DEFAULT:%.*]]
; CHECK: common.ret:
; CHECK-NEXT: [[COMMON_RET_OP:%.*]] = phi i32 [ [[TMP0:%.*]], [[DEFAULT]] ], [ [[TMP1:%.*]], [[A]] ]
; CHECK-NEXT: ret i32 [[COMMON_RET_OP]]
; CHECK: default:
; CHECK-NEXT: [[TMP0]] = call i32 @f(i32 0)
; CHECK-NEXT: br label [[COMMON_RET:%.*]]
; CHECK: a:
; CHECK-NEXT: [[TMP1]] = call i32 @f(i32 1)
; CHECK-NEXT: br label [[COMMON_RET]]
;
entry:
switch i32 %x, label %default [
i32 5, label %a
i32 6, label %a
i32 7, label %a
]
default:
%0 = call i32 @f(i32 0)
ret i32 %0
a:
%1 = call i32 @f(i32 1)
ret i32 %1
}
define i32 @unreachable(i32 %x) {
; CHECK-LABEL: @unreachable(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X_OFF:%.*]] = add i32 [[X:%.*]], -5
; CHECK-NEXT: [[SWITCH:%.*]] = icmp ult i32 [[X_OFF]], 3
; CHECK-NEXT: br i1 [[SWITCH]], label [[A:%.*]], label [[B:%.*]]
; CHECK: common.ret:
; CHECK-NEXT: [[COMMON_RET_OP:%.*]] = phi i32 [ [[TMP0:%.*]], [[A]] ], [ [[TMP1:%.*]], [[B]] ]
; CHECK-NEXT: ret i32 [[COMMON_RET_OP]]
; CHECK: a:
; CHECK-NEXT: [[TMP0]] = call i32 @f(i32 0)
; CHECK-NEXT: br label [[COMMON_RET:%.*]]
; CHECK: b:
; CHECK-NEXT: [[TMP1]] = call i32 @f(i32 1)
; CHECK-NEXT: br label [[COMMON_RET]]
;
entry:
switch i32 %x, label %unreachable [
i32 5, label %a
i32 6, label %a
i32 7, label %a
i32 10, label %b
i32 20, label %b
i32 30, label %b
i32 40, label %b
]
unreachable:
unreachable
a:
%0 = call i32 @f(i32 0)
ret i32 %0
b:
%1 = call i32 @f(i32 1)
ret i32 %1
}
define i32 @unreachable2(i32 %x) {
; CHECK-LABEL: @unreachable2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X_OFF:%.*]] = add i32 [[X:%.*]], -5
; CHECK-NEXT: [[SWITCH:%.*]] = icmp ult i32 [[X_OFF]], 3
; CHECK-NEXT: br i1 [[SWITCH]], label [[A:%.*]], label [[B:%.*]]
; CHECK: common.ret:
; CHECK-NEXT: [[COMMON_RET_OP:%.*]] = phi i32 [ [[TMP0:%.*]], [[A]] ], [ [[TMP1:%.*]], [[B]] ]
; CHECK-NEXT: ret i32 [[COMMON_RET_OP]]
; CHECK: a:
; CHECK-NEXT: [[TMP0]] = call i32 @f(i32 0)
; CHECK-NEXT: br label [[COMMON_RET:%.*]]
; CHECK: b:
; CHECK-NEXT: [[TMP1]] = call i32 @f(i32 1)
; CHECK-NEXT: br label [[COMMON_RET]]
;
entry:
; Note: folding the most popular case destination into the default
; would prevent switch-to-icmp here.
switch i32 %x, label %unreachable [
i32 5, label %a
i32 6, label %a
i32 7, label %a
i32 10, label %b
i32 20, label %b
]
unreachable:
unreachable
a:
%0 = call i32 @f(i32 0)
ret i32 %0
b:
%1 = call i32 @f(i32 1)
ret i32 %1
}
; This would crash because we did not clean up the
; default block of the switch before removing the switch.
define void @PR42737(i32* %a, i1 %c) {
; CHECK-LABEL: @PR42737(
; CHECK-NEXT: entry:
; CHECK-NEXT: unreachable
;
entry:
br i1 %c, label %switch, label %else
else:
store i32 2, i32* %a
br label %switch
switch:
%cleanup.dest1 = phi i32 [ 0, %else ], [ 3, %entry ]
switch i32 %cleanup.dest1, label %unreach1 [
i32 0, label %cleanup1
i32 3, label %cleanup2
]
cleanup1:
br label %unreach2
cleanup2:
br label %unreach2
unreach1:
%phi2 = phi i32 [ %cleanup.dest1, %switch ]
unreachable
unreach2:
unreachable
}
|
