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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt %s -simplifycfg -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: default:
; CHECK-NEXT: [[TMP0:%.*]] = call i32 @f(i32 0)
; CHECK-NEXT: ret i32 [[TMP0]]
; CHECK: a:
; CHECK-NEXT: [[TMP1:%.*]] = call i32 @f(i32 1)
; CHECK-NEXT: ret i32 [[TMP1]]
;
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: a:
; CHECK-NEXT: [[TMP0:%.*]] = call i32 @f(i32 0)
; CHECK-NEXT: ret i32 [[TMP0]]
; CHECK: b:
; CHECK-NEXT: [[TMP1:%.*]] = call i32 @f(i32 1)
; CHECK-NEXT: ret i32 [[TMP1]]
;
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: a:
; CHECK-NEXT: [[TMP0:%.*]] = call i32 @f(i32 0)
; CHECK-NEXT: ret i32 [[TMP0]]
; CHECK: b:
; CHECK-NEXT: [[TMP1:%.*]] = call i32 @f(i32 1)
; CHECK-NEXT: ret i32 [[TMP1]]
;
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
}
|
