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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -passes=simplifycfg -simplifycfg-require-and-preserve-domtree=1 -two-entry-phi-node-folding-threshold=4 -phi-node-folding-threshold=0 < %s | FileCheck %s
declare void @sideeffect0()
declare void @sideeffect1()
define i32 @unknown(i32 %a, i32 %b, i32 %c, i32 %d) {
; CHECK-LABEL: @unknown(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @sideeffect0()
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[V0:%.*]] = add i32 [[C:%.*]], [[D:%.*]]
; CHECK-NEXT: [[RES:%.*]] = select i1 [[CMP]], i32 [[V0]], i32 0
; CHECK-NEXT: call void @sideeffect1()
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
call void @sideeffect0()
%cmp = icmp eq i32 %a, %b
br i1 %cmp, label %cond.true, label %end
cond.true:
%v0 = add i32 %c, %d
br label %end
end:
%res = phi i32 [ %v0, %cond.true ], [ 0, %entry ]
call void @sideeffect1()
ret i32 %res
}
define i32 @predictably_taken(i32 %a, i32 %b, i32 %c, i32 %d) {
; CHECK-LABEL: @predictably_taken(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @sideeffect0()
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[V0:%.*]] = add i32 [[C:%.*]], [[D:%.*]]
; CHECK-NEXT: [[RES:%.*]] = select i1 [[CMP]], i32 [[V0]], i32 0, !prof [[PROF0:![0-9]+]]
; CHECK-NEXT: call void @sideeffect1()
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
call void @sideeffect0()
%cmp = icmp eq i32 %a, %b
br i1 %cmp, label %cond.true, label %end, !prof !0 ; likely branches to %cond.true
cond.true:
%v0 = add i32 %c, %d
br label %end
end:
%res = phi i32 [ %v0, %cond.true ], [ 0, %entry ]
call void @sideeffect1()
ret i32 %res
}
define i32 @predictably_nontaken(i32 %a, i32 %b, i32 %c, i32 %d) {
; CHECK-LABEL: @predictably_nontaken(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @sideeffect0()
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: br i1 [[CMP]], label [[END:%.*]], label [[COND_TRUE:%.*]], !prof [[PROF0]]
; CHECK: cond.true:
; CHECK-NEXT: [[V0:%.*]] = add i32 [[C:%.*]], [[D:%.*]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[V0]], [[COND_TRUE]] ], [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: call void @sideeffect1()
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
call void @sideeffect0()
%cmp = icmp eq i32 %a, %b
br i1 %cmp, label %end, label %cond.true, !prof !0 ; likely branches to %end
cond.true:
%v0 = add i32 %c, %d
br label %end
end:
%res = phi i32 [ %v0, %cond.true ], [ 0, %entry ]
call void @sideeffect1()
ret i32 %res
}
define i32 @almost_predictably_nontaken(i32 %a, i32 %b, i32 %c, i32 %d) {
; CHECK-LABEL: @almost_predictably_nontaken(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @sideeffect0()
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[V0:%.*]] = add i32 [[C:%.*]], [[D:%.*]]
; CHECK-NEXT: [[RES:%.*]] = select i1 [[CMP]], i32 0, i32 [[V0]], !prof [[PROF1:![0-9]+]]
; CHECK-NEXT: call void @sideeffect1()
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
call void @sideeffect0()
%cmp = icmp eq i32 %a, %b
br i1 %cmp, label %end, label %cond.true, !prof !1 ; probably likely branches to %end
cond.true:
%v0 = add i32 %c, %d
br label %end
end:
%res = phi i32 [ %v0, %cond.true ], [ 0, %entry ]
call void @sideeffect1()
ret i32 %res
}
define i32 @unpredictable(i32 %a, i32 %b, i32 %c, i32 %d) {
; CHECK-LABEL: @unpredictable(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @sideeffect0()
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[V0:%.*]] = add i32 [[C:%.*]], [[D:%.*]]
; CHECK-NEXT: [[RES:%.*]] = select i1 [[CMP]], i32 [[V0]], i32 0, !unpredictable [[META2:![0-9]+]]
; CHECK-NEXT: call void @sideeffect1()
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
call void @sideeffect0()
%cmp = icmp eq i32 %a, %b
br i1 %cmp, label %cond.true, label %end, !unpredictable !2 ; unpredictable
cond.true:
%v0 = add i32 %c, %d
br label %end
end:
%res = phi i32 [ %v0, %cond.true ], [ 0, %entry ]
call void @sideeffect1()
ret i32 %res
}
define i32 @unpredictable_yet_taken(i32 %a, i32 %b, i32 %c, i32 %d) {
; CHECK-LABEL: @unpredictable_yet_taken(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @sideeffect0()
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[V0:%.*]] = add i32 [[C:%.*]], [[D:%.*]]
; CHECK-NEXT: [[RES:%.*]] = select i1 [[CMP]], i32 [[V0]], i32 0, !prof [[PROF0]], !unpredictable [[META2]]
; CHECK-NEXT: call void @sideeffect1()
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
call void @sideeffect0()
%cmp = icmp eq i32 %a, %b
br i1 %cmp, label %cond.true, label %end, !prof !0, !unpredictable !2 ; likely branches to %cond.true, yet unpredictable
cond.true:
%v0 = add i32 %c, %d
br label %end
end:
%res = phi i32 [ %v0, %cond.true ], [ 0, %entry ]
call void @sideeffect1()
ret i32 %res
}
define i32 @unpredictable_yet_nontaken(i32 %a, i32 %b, i32 %c, i32 %d) {
; CHECK-LABEL: @unpredictable_yet_nontaken(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @sideeffect0()
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[V0:%.*]] = add i32 [[C:%.*]], [[D:%.*]]
; CHECK-NEXT: [[RES:%.*]] = select i1 [[CMP]], i32 0, i32 [[V0]], !prof [[PROF0]], !unpredictable [[META2]]
; CHECK-NEXT: call void @sideeffect1()
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
call void @sideeffect0()
%cmp = icmp eq i32 %a, %b
br i1 %cmp, label %end, label %cond.true, !prof !0, !unpredictable !2 ; likely branches to %end, yet unpredictable
cond.true:
%v0 = add i32 %c, %d
br label %end
end:
%res = phi i32 [ %v0, %cond.true ], [ 0, %entry ]
call void @sideeffect1()
ret i32 %res
}
!0 = !{!"branch_weights", i32 99, i32 1}
!1 = !{!"branch_weights", i32 70, i32 1}
!2 = !{}
; CHECK: !0 = !{!"branch_weights", i32 99, i32 1}
; CHECK: !1 = !{!"branch_weights", i32 70, i32 1}
; CHECK: !2 = !{}
|
