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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -passes=instsimplify < %s | FileCheck %s
declare void @bar(ptr %a, ptr nonnull noundef %b)
declare void @bar_without_noundef(ptr %a, ptr nonnull %b)
; 'y' must be nonnull.
define i1 @caller1(ptr %x, ptr %y) {
; CHECK-LABEL: @caller1(
; CHECK-NEXT: call void @bar(ptr [[X:%.*]], ptr [[Y:%.*]])
; CHECK-NEXT: ret i1 false
;
call void @bar(ptr %x, ptr %y)
%null_check = icmp eq ptr %y, null
ret i1 %null_check
}
; Don't know anything about 'y'.
define i1 @caller1_maybepoison(ptr %x, ptr %y) {
; CHECK-LABEL: @caller1_maybepoison(
; CHECK-NEXT: call void @bar_without_noundef(ptr [[X:%.*]], ptr [[Y:%.*]])
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[Y]], null
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
call void @bar_without_noundef(ptr %x, ptr %y)
%null_check = icmp eq ptr %y, null
ret i1 %null_check
}
; Don't know anything about 'y'.
define i1 @caller2(ptr %x, ptr %y) {
; CHECK-LABEL: @caller2(
; CHECK-NEXT: call void @bar(ptr [[Y:%.*]], ptr [[X:%.*]])
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[Y]], null
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
call void @bar(ptr %y, ptr %x)
%null_check = icmp eq ptr %y, null
ret i1 %null_check
}
; 'y' must be nonnull.
define i1 @caller3(ptr %x, ptr %y) {
; CHECK-LABEL: @caller3(
; CHECK-NEXT: call void @bar(ptr [[X:%.*]], ptr [[Y:%.*]])
; CHECK-NEXT: ret i1 true
;
call void @bar(ptr %x, ptr %y)
%null_check = icmp ne ptr %y, null
ret i1 %null_check
}
; FIXME: The call is guaranteed to execute, so 'y' must be nonnull throughout.
define i1 @caller4(ptr %x, ptr %y) {
; CHECK-LABEL: @caller4(
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp ne ptr [[Y:%.*]], null
; CHECK-NEXT: call void @bar(ptr [[X:%.*]], ptr [[Y]])
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
%null_check = icmp ne ptr %y, null
call void @bar(ptr %x, ptr %y)
ret i1 %null_check
}
; The call to bar() does not dominate the null check, so no change.
define i1 @caller5(ptr %x, ptr %y) {
; CHECK-LABEL: @caller5(
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[Y:%.*]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[T:%.*]], label [[F:%.*]]
; CHECK: t:
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
; CHECK: f:
; CHECK-NEXT: call void @bar(ptr [[X:%.*]], ptr [[Y]])
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
%null_check = icmp eq ptr %y, null
br i1 %null_check, label %t, label %f
t:
ret i1 %null_check
f:
call void @bar(ptr %x, ptr %y)
ret i1 %null_check
}
; Make sure that an invoke works similarly to a call.
declare i32 @esfp(...)
define i1 @caller6(ptr %x, ptr %y) personality ptr @esfp{
; CHECK-LABEL: @caller6(
; CHECK-NEXT: invoke void @bar(ptr [[X:%.*]], ptr nonnull [[Y:%.*]])
; CHECK-NEXT: to label [[CONT:%.*]] unwind label [[EXC:%.*]]
; CHECK: cont:
; CHECK-NEXT: ret i1 false
; CHECK: exc:
; CHECK-NEXT: [[LP:%.*]] = landingpad { ptr, i32 }
; CHECK-NEXT: filter [0 x ptr] zeroinitializer
; CHECK-NEXT: unreachable
;
invoke void @bar(ptr %x, ptr nonnull %y)
to label %cont unwind label %exc
cont:
%null_check = icmp eq ptr %y, null
ret i1 %null_check
exc:
%lp = landingpad { ptr, i32 }
filter [0 x ptr] zeroinitializer
unreachable
}
declare ptr @returningPtr(ptr returned %p)
define i1 @nonnullReturnTest(ptr nonnull %x) {
; CHECK-LABEL: @nonnullReturnTest(
; CHECK-NEXT: [[X2:%.*]] = call ptr @returningPtr(ptr [[X:%.*]])
; CHECK-NEXT: ret i1 false
;
%x2 = call ptr @returningPtr(ptr %x)
%null_check = icmp eq ptr %x2, null
ret i1 %null_check
}
define i1 @unknownReturnTest(ptr %x) {
; CHECK-LABEL: @unknownReturnTest(
; CHECK-NEXT: [[X2:%.*]] = call ptr @returningPtr(ptr [[X:%.*]])
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[X2]], null
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
%x2 = call ptr @returningPtr(ptr %x)
%null_check = icmp eq ptr %x2, null
ret i1 %null_check
}
; Make sure that if load/store happened, the pointer is nonnull.
define i32 @test_null_after_store(ptr %0) {
; CHECK-LABEL: @test_null_after_store(
; CHECK-NEXT: store i32 123, ptr [[TMP0:%.*]], align 4
; CHECK-NEXT: ret i32 2
;
store i32 123, ptr %0, align 4
%2 = icmp eq ptr %0, null
%3 = select i1 %2, i32 1, i32 2
ret i32 %3
}
define i32 @test_null_after_load(ptr %0) {
; CHECK-LABEL: @test_null_after_load(
; CHECK-NEXT: ret i32 1
;
%2 = load i32, ptr %0, align 4
%3 = icmp eq ptr %0, null
%4 = select i1 %3, i32 %2, i32 1
ret i32 %4
}
; Make sure that different address space does not affect null pointer check.
define i32 @test_null_after_store_addrspace(ptr addrspace(1) %0) {
; CHECK-LABEL: @test_null_after_store_addrspace(
; CHECK-NEXT: store i32 123, ptr addrspace(1) [[TMP0:%.*]], align 4
; CHECK-NEXT: [[TMP2:%.*]] = icmp eq ptr addrspace(1) [[TMP0]], null
; CHECK-NEXT: [[TMP3:%.*]] = select i1 [[TMP2]], i32 1, i32 2
; CHECK-NEXT: ret i32 [[TMP3]]
;
store i32 123, ptr addrspace(1) %0, align 4
%2 = icmp eq ptr addrspace(1) %0, null
%3 = select i1 %2, i32 1, i32 2
ret i32 %3
}
define i32 @test_null_after_load_addrspace(ptr addrspace(1) %0) {
; CHECK-LABEL: @test_null_after_load_addrspace(
; CHECK-NEXT: [[TMP2:%.*]] = load i32, ptr addrspace(1) [[TMP0:%.*]], align 4
; CHECK-NEXT: [[TMP3:%.*]] = icmp eq ptr addrspace(1) [[TMP0]], null
; CHECK-NEXT: [[TMP4:%.*]] = select i1 [[TMP3]], i32 [[TMP2]], i32 1
; CHECK-NEXT: ret i32 [[TMP4]]
;
%2 = load i32, ptr addrspace(1) %0, align 4
%3 = icmp eq ptr addrspace(1) %0, null
%4 = select i1 %3, i32 %2, i32 1
ret i32 %4
}
; Make sure if store happened after the check, nullptr check is not removed.
declare ptr @func(i64)
define ptr @test_load_store_after_check(ptr %0) {
; CHECK-LABEL: @test_load_store_after_check(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP1:%.*]] = call ptr @func(i64 0)
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[TMP1]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[RETURN:%.*]], label [[IF_END:%.*]]
; CHECK: if.end:
; CHECK-NEXT: store i8 7, ptr [[TMP1]], align 1
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RETVAL_0:%.*]] = phi ptr [ [[TMP1]], [[IF_END]] ], [ null, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret ptr [[RETVAL_0]]
;
entry:
%1 = call ptr @func(i64 0)
%null_check = icmp eq ptr %1, null
br i1 %null_check, label %return, label %if.end
if.end:
store i8 7, ptr %1
br label %return
return:
%retval.0 = phi ptr [ %1, %if.end ], [ null, %entry ]
ret ptr %retval.0
}
define i1 @test_known_nonnull_at_callsite(ptr %src) {
; CHECK-LABEL: @test_known_nonnull_at_callsite(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @callee(ptr noundef nonnull [[SRC:%.*]])
; CHECK-NEXT: ret i1 false
;
entry:
call void @callee(ptr noundef nonnull %src)
%nonnull = icmp eq ptr %src, null
ret i1 %nonnull
}
define i1 @test_known_nonnull_mixed(ptr %src) {
; CHECK-LABEL: @test_known_nonnull_mixed(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @callee2(ptr nonnull [[SRC:%.*]])
; CHECK-NEXT: ret i1 false
;
entry:
call void @callee2(ptr nonnull %src)
%nonnull = icmp eq ptr %src, null
ret i1 %nonnull
}
define i1 @test_known_nonnull_at_callsite_dereferenceable(ptr %src) {
; CHECK-LABEL: @test_known_nonnull_at_callsite_dereferenceable(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @callee(ptr dereferenceable(1) [[SRC:%.*]])
; CHECK-NEXT: ret i1 false
;
entry:
call void @callee(ptr dereferenceable(1) %src)
%nonnull = icmp eq ptr %src, null
ret i1 %nonnull
}
; Negative tests
define i1 @test_known_nonnull_at_callsite_without_noundef(ptr %src) {
; CHECK-LABEL: @test_known_nonnull_at_callsite_without_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @callee(ptr nonnull [[SRC:%.*]])
; CHECK-NEXT: [[NONNULL:%.*]] = icmp eq ptr [[SRC]], null
; CHECK-NEXT: ret i1 [[NONNULL]]
;
entry:
call void @callee(ptr nonnull %src)
%nonnull = icmp eq ptr %src, null
ret i1 %nonnull
}
define i1 @test_known_nonnull_at_callsite_dereferenceable_null_is_defined(ptr %src) null_pointer_is_valid {
; CHECK-LABEL: @test_known_nonnull_at_callsite_dereferenceable_null_is_defined(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @callee(ptr dereferenceable(1) [[SRC:%.*]])
; CHECK-NEXT: [[NONNULL:%.*]] = icmp eq ptr [[SRC]], null
; CHECK-NEXT: ret i1 [[NONNULL]]
;
entry:
call void @callee(ptr dereferenceable(1) %src)
%nonnull = icmp eq ptr %src, null
ret i1 %nonnull
}
declare void @callee(ptr)
declare void @callee2(ptr noundef)
|
