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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes='simplifycfg<hoist-common-insts;no-sink-common-insts>' -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck %s
define i1 @common_instr_with_unreachable(i64 %a, i64 %b, i64 %c) {
; CHECK-LABEL: @common_instr_with_unreachable(
; CHECK-NEXT: start:
; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i64 [[B:%.*]], [[C:%.*]]
; CHECK-NEXT: ret i1 [[TMP0]]
;
start:
switch i64 %a, label %unreachable [
i64 0, label %bb0
i64 1, label %bb1
i64 2, label %bb2
]
unreachable:
unreachable
bb0: ; preds = %start
%0 = icmp eq i64 %b, %c
br label %exit
bb1: ; preds = %start
%1 = icmp eq i64 %b, %c
br label %exit
bb2: ; preds = %start
%2 = icmp eq i64 %b, %c
br label %exit
exit: ; preds = %bb2, %bb1, %bb0
%result = phi i1 [ %0, %bb0 ], [ %1, %bb1 ], [ %2, %bb2 ]
ret i1 %result
}
define i1 @common_instr_with_unreachable_2(i64 %a, i64 %b, i64 %c) {
; CHECK-LABEL: @common_instr_with_unreachable_2(
; CHECK-NEXT: start:
; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i64 [[B:%.*]], [[C:%.*]]
; CHECK-NEXT: ret i1 [[TMP0]]
;
start:
switch i64 %a, label %bb1 [
i64 0, label %bb0
i64 1, label %unreachable
i64 2, label %bb2
]
unreachable:
unreachable
bb0: ; preds = %start
%0 = icmp eq i64 %b, %c
br label %exit
bb1: ; preds = %start
%1 = icmp eq i64 %b, %c
br label %exit
bb2: ; preds = %start
%2 = icmp eq i64 %b, %c
br label %exit
exit: ; preds = %bb2, %bb1, %bb0
%result = phi i1 [ %0, %bb0 ], [ %1, %bb1 ], [ %2, %bb2 ]
ret i1 %result
}
define i1 @not_only_unreachable(i64 %a, i64 %b, i64 %c) {
; CHECK-LABEL: @not_only_unreachable(
; CHECK-NEXT: start:
; CHECK-NEXT: switch i64 [[A:%.*]], label [[UNREACHABLE:%.*]] [
; CHECK-NEXT: i64 0, label [[BB0:%.*]]
; CHECK-NEXT: i64 1, label [[BB1:%.*]]
; CHECK-NEXT: i64 2, label [[BB2:%.*]]
; CHECK-NEXT: ]
; CHECK: unreachable:
; CHECK-NEXT: call void @no_return()
; CHECK-NEXT: unreachable
; CHECK: bb0:
; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i64 [[B:%.*]], [[C:%.*]]
; CHECK-NEXT: call void @foo()
; CHECK-NEXT: br label [[EXIT:%.*]]
; CHECK: bb1:
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i64 [[B]], [[C]]
; CHECK-NEXT: call void @foo()
; CHECK-NEXT: br label [[EXIT]]
; CHECK: bb2:
; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i64 [[B]], [[C]]
; CHECK-NEXT: call void @foo()
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i1 [ [[TMP0]], [[BB0]] ], [ [[TMP1]], [[BB1]] ], [ [[TMP2]], [[BB2]] ]
; CHECK-NEXT: ret i1 [[RESULT]]
;
start:
switch i64 %a, label %unreachable [
i64 0, label %bb0
i64 1, label %bb1
i64 2, label %bb2
]
unreachable:
call void @no_return()
unreachable
bb0: ; preds = %start
%0 = icmp eq i64 %b, %c
call void @foo()
br label %exit
bb1: ; preds = %start
%1 = icmp eq i64 %b, %c
call void @foo()
br label %exit
bb2: ; preds = %start
%2 = icmp eq i64 %b, %c
call void @foo()
br label %exit
exit: ; preds = %bb2, %bb1, %bb0
%result = phi i1 [ %0, %bb0 ], [ %1, %bb1 ], [ %2, %bb2 ]
ret i1 %result
}
; If we can hoist a musttail call,
; we can and have to hoist subsequent bitcast and ret instructions.
define ptr @switch_musttail_call(ptr %arg) {
; CHECK-LABEL: @switch_musttail_call(
; CHECK-NEXT: bb:
; CHECK-NEXT: [[P0:%.*]] = musttail call ptr @musttail_call(ptr [[ARG:%.*]])
; CHECK-NEXT: ret ptr [[P0]]
;
bb:
%load = load i16, ptr %arg, align 2
switch i16 %load, label %unreachable [
i16 0, label %bb0
i16 1, label %bb1
i16 2, label %bb2
]
unreachable:
unreachable
bb0:
%p0 = musttail call ptr @musttail_call(ptr %arg)
ret ptr %p0
bb1:
%p1 = musttail call ptr @musttail_call(ptr %arg)
ret ptr %p1
bb2:
%p2 = musttail call ptr @musttail_call(ptr %arg)
ret ptr %p2
}
declare void @no_return()
declare void @foo()
declare ptr @musttail_call(ptr)
|
