; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=tailcallelim -verify-dom-info -S | FileCheck %s
; This test checks that TRE would be done for only one recursive call.
; The test_multiple_exits function has three recursive calls.
; First recursive call could not be eliminated because there is
; escaped pointer to local variable. Second recursive call could
; be eliminated. Thrid recursive call could not be eliminated since
; this is not last call. Thus, test checks that TRE would be done
; for only second recursive call.
; IR for that test was generated from the following C++ source:
;
; void capture_arg (int*);
; void test_multiple_exits (int param);
; if (param >= 0 && param < 10) {
; int temp;
; capture_arg(&temp);
; // TRE could not be done because pointer to local
; // variable "temp" is escaped.
; test_multiple_exits(param + 1);
; } else if (param >=10 && param < 20) {
; // TRE should be done.
; test_multiple_exits(param + 1);
; } else if (param >= 20 && param < 22) {
; // TRE could not be done since recursive
; // call is not last call.
; test_multiple_exits(param + 1);
; func();
; }
;
; return;
; }
; Function Attrs: noinline optnone uwtable
declare void @_Z11capture_argPi(ptr %param) #0
; Function Attrs: noinline optnone uwtable
declare void @_Z4funcv() #0
; Function Attrs: noinline nounwind uwtable
define dso_local void @_Z19test_multiple_exitsi(i32 %param) local_unnamed_addr #2 {
; CHECK-LABEL: @_Z19test_multiple_exitsi(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TEMP:%.*]] = alloca i32, align 4
; CHECK-NEXT: br label [[TAILRECURSE:%.*]]
; CHECK: tailrecurse:
; CHECK-NEXT: [[PARAM_TR:%.*]] = phi i32 [ [[PARAM:%.*]], [[ENTRY:%.*]] ], [ [[ADD6:%.*]], [[IF_THEN5:%.*]] ]
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[PARAM_TR]], 10
; CHECK-NEXT: br i1 [[TMP0]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
; CHECK: if.then:
; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 4, ptr nonnull [[TEMP]]) #1
; CHECK-NEXT: call void @_Z11capture_argPi(ptr nonnull [[TEMP]])
; CHECK-NEXT: [[ADD:%.*]] = add nuw nsw i32 [[PARAM_TR]], 1
; CHECK-NEXT: call void @_Z19test_multiple_exitsi(i32 [[ADD]])
; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 4, ptr nonnull [[TEMP]]) #1
; CHECK-NEXT: br label [[IF_END14:%.*]]
; CHECK: if.else:
; CHECK-NEXT: [[PARAM_OFF:%.*]] = add i32 [[PARAM_TR]], -10
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i32 [[PARAM_OFF]], 10
; CHECK-NEXT: br i1 [[TMP2]], label [[IF_THEN5]], label [[IF_ELSE7:%.*]]
; CHECK: if.then5:
; CHECK-NEXT: [[ADD6]] = add nuw nsw i32 [[PARAM_TR]], 1
; CHECK-NEXT: br label [[TAILRECURSE]]
; CHECK: if.else7:
; CHECK-NEXT: [[TMP3:%.*]] = and i32 [[PARAM_TR]], -2
; CHECK-NEXT: [[TMP4:%.*]] = icmp eq i32 [[TMP3]], 20
; CHECK-NEXT: br i1 [[TMP4]], label [[IF_THEN11:%.*]], label [[IF_END14]]
; CHECK: if.then11:
; CHECK-NEXT: [[ADD12:%.*]] = add nsw i32 [[PARAM_TR]], 1
; CHECK-NEXT: tail call void @_Z19test_multiple_exitsi(i32 [[ADD12]])
; CHECK-NEXT: tail call void @_Z4funcv()
; CHECK-NEXT: ret void
; CHECK: if.end14:
; CHECK-NEXT: ret void
;
entry:
%temp = alloca i32, align 4
%0 = icmp ult i32 %param, 10
br i1 %0, label %if.then, label %if.else
if.then: ; preds = %entry
call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %temp) #2
call void @_Z11capture_argPi(ptr nonnull %temp)
%add = add nuw nsw i32 %param, 1
call void @_Z19test_multiple_exitsi(i32 %add)
call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %temp) #2
br label %if.end14
if.else: ; preds = %entry
%param.off = add i32 %param, -10
%1 = icmp ult i32 %param.off, 10
br i1 %1, label %if.then5, label %if.else7
if.then5: ; preds = %if.else
%add6 = add nuw nsw i32 %param, 1
call void @_Z19test_multiple_exitsi(i32 %add6)
br label %if.end14
if.else7: ; preds = %if.else
%2 = and i32 %param, -2
%3 = icmp eq i32 %2, 20
br i1 %3, label %if.then11, label %if.end14
if.then11: ; preds = %if.else7
%add12 = add nsw i32 %param, 1
call void @_Z19test_multiple_exitsi(i32 %add12)
call void @_Z4funcv()
br label %if.end14
if.end14: ; preds = %if.then5, %if.then11, %if.else7, %if.then
ret void
}
; Function Attrs: argmemonly nounwind willreturn
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2
; Function Attrs: argmemonly nounwind willreturn
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2
attributes #0 = { nofree noinline norecurse nounwind uwtable }
attributes #1 = { nounwind uwtable }
attributes #2 = { argmemonly nounwind willreturn }
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