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|
; RUN: opt -S -functionattrs -enable-nonnull-arg-prop %s | FileCheck %s --check-prefixes=BOTH,FNATTR
; RUN: opt -S -passes=function-attrs -enable-nonnull-arg-prop %s | FileCheck %s --check-prefixes=BOTH,FNATTR
; RUN: opt -attributor --attributor-disable=false -S < %s | FileCheck %s --check-prefixes=BOTH,ATTRIBUTOR
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
declare nonnull i8* @ret_nonnull()
; Return a pointer trivially nonnull (call return attribute)
define i8* @test1() {
; BOTH: define nonnull i8* @test1
%ret = call i8* @ret_nonnull()
ret i8* %ret
}
; Return a pointer trivially nonnull (argument attribute)
define i8* @test2(i8* nonnull %p) {
; BOTH: define nonnull i8* @test2
ret i8* %p
}
; Given an SCC where one of the functions can not be marked nonnull,
; can we still mark the other one which is trivially nonnull
define i8* @scc_binder() {
; BOTH: define i8* @scc_binder
call i8* @test3()
ret i8* null
}
define i8* @test3() {
; BOTH: define nonnull i8* @test3
call i8* @scc_binder()
%ret = call i8* @ret_nonnull()
ret i8* %ret
}
; Given a mutual recursive set of functions, we can mark them
; nonnull if neither can ever return null. (In this case, they
; just never return period.)
define i8* @test4_helper() {
; FNATTR: define noalias nonnull i8* @test4_helper
; ATTRIBUTOR: define nonnull i8* @test4_helper
%ret = call i8* @test4()
ret i8* %ret
}
define i8* @test4() {
; FNATTR: define noalias nonnull i8* @test4
; ATTRIBUTOR: define nonnull i8* @test4
%ret = call i8* @test4_helper()
ret i8* %ret
}
; Given a mutual recursive set of functions which *can* return null
; make sure we haven't marked them as nonnull.
define i8* @test5_helper() {
; FNATTR: define noalias i8* @test5_helper
; ATTRIBUTOR: define i8* @test5_helper
%ret = call i8* @test5()
ret i8* null
}
define i8* @test5() {
; FNATTR: define noalias i8* @test5
; ATTRIBUTOR: define i8* @test5
%ret = call i8* @test5_helper()
ret i8* %ret
}
; Local analysis, but going through a self recursive phi
define i8* @test6() {
entry:
; BOTH: define nonnull i8* @test6
%ret = call i8* @ret_nonnull()
br label %loop
loop:
%phi = phi i8* [%ret, %entry], [%phi, %loop]
br i1 undef, label %loop, label %exit
exit:
ret i8* %phi
}
; BOTH: define i8* @test7
define i8* @test7(i8* %a) {
%b = getelementptr inbounds i8, i8* %a, i64 0
ret i8* %b
}
; BOTH: define nonnull i8* @test8
define i8* @test8(i8* %a) {
%b = getelementptr inbounds i8, i8* %a, i64 1
ret i8* %b
}
; BOTH: define i8* @test9
define i8* @test9(i8* %a, i64 %n) {
%b = getelementptr inbounds i8, i8* %a, i64 %n
ret i8* %b
}
declare void @llvm.assume(i1)
; FNATTR: define i8* @test10
; FIXME: missing nonnull
; ATTRIBUTOR: define i8* @test10
define i8* @test10(i8* %a, i64 %n) {
%cmp = icmp ne i64 %n, 0
call void @llvm.assume(i1 %cmp)
%b = getelementptr inbounds i8, i8* %a, i64 %n
ret i8* %b
}
; TEST 11
; char* test11(char *p) {
; return p? p: nonnull();
; }
; FNATTR: define i8* @test11
; FIXME: missing nonnull
; ATTRIBUTOR: define i8* @test11
define i8* @test11(i8*) local_unnamed_addr {
%2 = icmp eq i8* %0, null
br i1 %2, label %3, label %5
; <label>:3: ; preds = %1
%4 = tail call i8* @ret_nonnull()
br label %5
; <label>:5: ; preds = %3, %1
%6 = phi i8* [ %4, %3 ], [ %0, %1 ]
ret i8* %6
}
; TEST 12
; Simple CallSite Test
declare void @test12_helper(i8*)
define void @test12(i8* nonnull %a) {
; ATTRIBUTOR: define void @test12(i8* nonnull %a)
; ATTRIBUTOR-NEXT: tail call void @test12_helper(i8* nonnull %a)
tail call void @test12_helper(i8* %a)
ret void
}
; TEST 13
; Simple Argument Tests
declare i8* @unknown()
define void @test13_helper() {
%nonnullptr = tail call i8* @ret_nonnull()
%maybenullptr = tail call i8* @unknown()
tail call void @test13(i8* %nonnullptr, i8* %nonnullptr, i8* %maybenullptr)
tail call void @test13(i8* %nonnullptr, i8* %maybenullptr, i8* %nonnullptr)
ret void
}
define internal void @test13(i8* %a, i8* %b, i8* %c) {
; ATTRIBUTOR: define internal void @test13(i8* nonnull %a, i8* %b, i8* %c)
ret void
}
declare nonnull i8* @nonnull()
; TEST 14
; Complex propagation
; Argument of f1, f2, f3 can be marked with nonnull.
; * Argument
; 1. In f1:bb6, %arg can be marked with nonnull because of the comparison in bb1
; 2. Because f2 is internal function, f2(i32* %arg) -> @f2(i32* nonnull %arg)
; 3. In f1:bb4 %tmp5 is nonnull and f3 is internal function.
; Then, f3(i32* %arg) -> @f3(i32* nonnull %arg)
; 4. We get nonnull in whole f1 call sites so f1(i32* %arg) -> @f1(i32* nonnull %arg)
define internal i32* @f1(i32* %arg) {
; FIXME: missing nonnull It should be nonnull @f1(i32* nonnull %arg)
; ATTRIBUTOR: define internal nonnull i32* @f1(i32* %arg)
bb:
%tmp = icmp eq i32* %arg, null
br i1 %tmp, label %bb9, label %bb1
bb1: ; preds = %bb
%tmp2 = load i32, i32* %arg, align 4
%tmp3 = icmp eq i32 %tmp2, 0
br i1 %tmp3, label %bb6, label %bb4
bb4: ; preds = %bb1
%tmp5 = getelementptr inbounds i32, i32* %arg, i64 1
; ATTRIBUTOR: %tmp5b = tail call i32* @f3(i32* nonnull %tmp5)
%tmp5b = tail call i32* @f3(i32* %tmp5)
br label %bb9
bb6: ; preds = %bb1
; FIXME: missing nonnull. It should be @f2(i32* nonnull %arg)
; ATTRIBUTOR: %tmp7 = tail call i32* @f2(i32* %arg)
%tmp7 = tail call i32* @f2(i32* %arg)
ret i32* %tmp7
bb9: ; preds = %bb4, %bb
%tmp10 = phi i32* [ %tmp5, %bb4 ], [ inttoptr (i64 4 to i32*), %bb ]
ret i32* %tmp10
}
define internal i32* @f2(i32* %arg) {
; FIXME: missing nonnull. It should be nonnull @f2(i32* nonnull %arg)
; ATTRIBUTOR: define internal nonnull i32* @f2(i32* %arg)
bb:
; FIXME: missing nonnull. It should be @f1(i32* nonnull %arg)
; ATTRIBUTOR: %tmp = tail call i32* @f1(i32* %arg)
%tmp = tail call i32* @f1(i32* %arg)
ret i32* %tmp
}
define dso_local noalias i32* @f3(i32* %arg) {
; FIXME: missing nonnull. It should be nonnull @f3(i32* nonnull %arg)
; ATTRIBUTOR: define dso_local noalias i32* @f3(i32* %arg)
bb:
; FIXME: missing nonnull. It should be @f1(i32* nonnull %arg)
; ATTRIBUTOR: %tmp = call i32* @f1(i32* %arg)
%tmp = call i32* @f1(i32* %arg)
ret i32* null
}
; Test propagation of nonnull callsite args back to caller.
declare void @use1(i8* %x)
declare void @use2(i8* %x, i8* %y);
declare void @use3(i8* %x, i8* %y, i8* %z);
declare void @use1nonnull(i8* nonnull %x);
declare void @use2nonnull(i8* nonnull %x, i8* nonnull %y);
declare void @use3nonnull(i8* nonnull %x, i8* nonnull %y, i8* nonnull %z);
declare i8 @use1safecall(i8* %x) readonly nounwind ; readonly+nounwind guarantees that execution continues to successor
; Can't extend non-null to parent for any argument because the 2nd call is not guaranteed to execute.
define void @parent1(i8* %a, i8* %b, i8* %c) {
; BOTH-LABEL: @parent1(i8* %a, i8* %b, i8* %c)
; BOTH-NEXT: call void @use3(i8* %c, i8* %a, i8* %b)
; FNATTR-NEXT: call void @use3nonnull(i8* %b, i8* %c, i8* %a)
; ATTRIBUTOR-NEXT: call void @use3nonnull(i8* nonnull %b, i8* nonnull %c, i8* nonnull %a)
; BOTH-NEXT: ret void
call void @use3(i8* %c, i8* %a, i8* %b)
call void @use3nonnull(i8* %b, i8* %c, i8* %a)
ret void
}
; Extend non-null to parent for all arguments.
define void @parent2(i8* %a, i8* %b, i8* %c) {
; FNATTR-LABEL: @parent2(i8* nonnull %a, i8* nonnull %b, i8* nonnull %c)
; FNATTR-NEXT: call void @use3nonnull(i8* %b, i8* %c, i8* %a)
; FNATTR-NEXT: call void @use3(i8* %c, i8* %a, i8* %b)
; FIXME: missing "nonnull", it should be
; @parent2(i8* nonnull %a, i8* nonnull %b, i8* nonnull %c)
; call void @use3nonnull(i8* nonnull %b, i8* nonnull %c, i8* nonnull %a)
; call void @use3(i8* nonnull %c, i8* nonnull %a, i8* nonnull %b)
; ATTRIBUTOR-LABEL: @parent2(i8* %a, i8* %b, i8* %c)
; ATTRIBUTOR-NEXT: call void @use3nonnull(i8* nonnull %b, i8* nonnull %c, i8* nonnull %a)
; ATTRIBUTOR-NEXT: call void @use3(i8* %c, i8* %a, i8* %b)
; BOTH-NEXT: ret void
call void @use3nonnull(i8* %b, i8* %c, i8* %a)
call void @use3(i8* %c, i8* %a, i8* %b)
ret void
}
; Extend non-null to parent for 1st argument.
define void @parent3(i8* %a, i8* %b, i8* %c) {
; FNATTR-LABEL: @parent3(i8* nonnull %a, i8* %b, i8* %c)
; FNATTR-NEXT: call void @use1nonnull(i8* %a)
; FNATTR-NEXT: call void @use3(i8* %c, i8* %b, i8* %a)
; FIXME: missing "nonnull", it should be,
; @parent3(i8* nonnull %a, i8* %b, i8* %c)
; call void @use1nonnull(i8* nonnull %a)
; call void @use3(i8* %c, i8* %b, i8* nonnull %a)
; ATTRIBUTOR-LABEL: @parent3(i8* %a, i8* %b, i8* %c)
; ATTRIBUTOR-NEXT: call void @use1nonnull(i8* nonnull %a)
; ATTRIBUTOR-NEXT: call void @use3(i8* %c, i8* %b, i8* %a)
; BOTH-NEXT: ret void
call void @use1nonnull(i8* %a)
call void @use3(i8* %c, i8* %b, i8* %a)
ret void
}
; Extend non-null to parent for last 2 arguments.
define void @parent4(i8* %a, i8* %b, i8* %c) {
; CHECK-LABEL: @parent4(i8* %a, i8* nonnull %b, i8* nonnull %c)
; CHECK-NEXT: call void @use2nonnull(i8* %c, i8* %b)
; CHECK-NEXT: call void @use2(i8* %a, i8* %c)
; CHECK-NEXT: call void @use1(i8* %b)
; FIXME : missing "nonnull", it should be
; @parent4(i8* %a, i8* nonnull %b, i8* nonnull %c)
; call void @use2nonnull(i8* nonnull %c, i8* nonull %b)
; call void @use2(i8* %a, i8* nonnull %c)
; call void @use1(i8* nonnull %b)
; ATTRIBUTOR-LABEL: @parent4(i8* %a, i8* %b, i8* %c)
; ATTRIBUTOR-NEXT: call void @use2nonnull(i8* nonnull %c, i8* nonnull %b)
; ATTRIBUTOR-NEXT: call void @use2(i8* %a, i8* %c)
; ATTRIBUTOR-NEXT: call void @use1(i8* %b)
; BOTH: ret void
call void @use2nonnull(i8* %c, i8* %b)
call void @use2(i8* %a, i8* %c)
call void @use1(i8* %b)
ret void
}
; The callsite must execute in order for the attribute to transfer to the parent.
; It appears benign to extend non-null to the parent in this case, but we can't do that
; because it would incorrectly propagate the wrong information to its callers.
define void @parent5(i8* %a, i1 %a_is_notnull) {
; BOTH: @parent5(i8* %a, i1 %a_is_notnull)
; BOTH-NEXT: br i1 %a_is_notnull, label %t, label %f
; BOTH: t:
; FNATTR-NEXT: call void @use1nonnull(i8* %a)
; ATTRIBUTOR-NEXT: call void @use1nonnull(i8* nonnull %a)
; BOTH-NEXT: ret void
; BOTH: f:
; BOTH-NEXT: ret void
br i1 %a_is_notnull, label %t, label %f
t:
call void @use1nonnull(i8* %a)
ret void
f:
ret void
}
; The callsite must execute in order for the attribute to transfer to the parent.
; The volatile load might trap, so there's no guarantee that we'll ever get to the call.
define i8 @parent6(i8* %a, i8* %b) {
; BOTH-LABEL: @parent6(i8* %a, i8* %b)
; BOTH-NEXT: [[C:%.*]] = load volatile i8, i8* %b
; FNATTR-NEXT: call void @use1nonnull(i8* %a)
; ATTRIBUTOR-NEXT: call void @use1nonnull(i8* nonnull %a)
; BOTH-NEXT: ret i8 [[C]]
%c = load volatile i8, i8* %b
call void @use1nonnull(i8* %a)
ret i8 %c
}
; The nonnull callsite is guaranteed to execute, so the argument must be nonnull throughout the parent.
define i8 @parent7(i8* %a) {
; FNATTR-LABEL: @parent7(i8* nonnull %a)
; FNATTR-NEXT: [[RET:%.*]] = call i8 @use1safecall(i8* %a)
; FNATTR-NEXT: call void @use1nonnull(i8* %a)
; FIXME : missing "nonnull", it should be
; @parent7(i8* nonnull %a)
; [[RET:%.*]] = call i8 @use1safecall(i8* nonnull %a)
; call void @use1nonnull(i8* nonnull %a)
; ret i8 [[RET]]
; ATTRIBUTOR-LABEL: @parent7(i8* %a)
; ATTRIBUTOR-NEXT: [[RET:%.*]] = call i8 @use1safecall(i8* %a)
; ATTRIBUTOR-NEXT: call void @use1nonnull(i8* nonnull %a)
; BOTH-NEXT: ret i8 [[RET]]
%ret = call i8 @use1safecall(i8* %a)
call void @use1nonnull(i8* %a)
ret i8 %ret
}
; Make sure that an invoke works similarly to a call.
declare i32 @esfp(...)
define i1 @parent8(i8* %a, i8* %bogus1, i8* %b) personality i8* bitcast (i32 (...)* @esfp to i8*){
; FNATTR-LABEL: @parent8(i8* nonnull %a, i8* nocapture readnone %bogus1, i8* nonnull %b)
; FIXME : missing "nonnull", it should be @parent8(i8* nonnull %a, i8* %bogus1, i8* nonnull %b)
; ATTRIBUTOR-LABEL: @parent8(i8* %a, i8* %bogus1, i8* %b)
; BOTH-NEXT: entry:
; FNATTR-NEXT: invoke void @use2nonnull(i8* %a, i8* %b)
; ATTRIBUTOR-NEXT: invoke void @use2nonnull(i8* nonnull %a, i8* nonnull %b)
; BOTH-NEXT: to label %cont unwind label %exc
; BOTH: cont:
; BOTH-NEXT: [[NULL_CHECK:%.*]] = icmp eq i8* %b, null
; BOTH-NEXT: ret i1 [[NULL_CHECK]]
; BOTH: exc:
; BOTH-NEXT: [[LP:%.*]] = landingpad { i8*, i32 }
; BOTH-NEXT: filter [0 x i8*] zeroinitializer
; BOTH-NEXT: unreachable
entry:
invoke void @use2nonnull(i8* %a, i8* %b)
to label %cont unwind label %exc
cont:
%null_check = icmp eq i8* %b, null
ret i1 %null_check
exc:
%lp = landingpad { i8*, i32 }
filter [0 x i8*] zeroinitializer
unreachable
}
; BOTH: define nonnull i32* @gep1(
define i32* @gep1(i32* %p) {
%q = getelementptr inbounds i32, i32* %p, i32 1
ret i32* %q
}
define i32* @gep1_no_null_opt(i32* %p) #0 {
; Should't be able to derive nonnull based on gep.
; BOTH: define i32* @gep1_no_null_opt(
%q = getelementptr inbounds i32, i32* %p, i32 1
ret i32* %q
}
; BOTH: define i32 addrspace(3)* @gep2(
define i32 addrspace(3)* @gep2(i32 addrspace(3)* %p) {
%q = getelementptr inbounds i32, i32 addrspace(3)* %p, i32 1
ret i32 addrspace(3)* %q
}
; BOTH: define internal nonnull i32* @g2()
define internal i32* @g2() {
ret i32* inttoptr (i64 4 to i32*)
}
define i32* @g1() {
%c = call i32* @g2()
ret i32* %c
}
attributes #0 = { "null-pointer-is-valid"="true" }
|
