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| ; RUN: opt -instcombine -S < %s | FileCheck %s
;
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
declare void @foo(i8*)
declare void @bar(i8 addrspace(1)*)
define void @nonnullAfterBitCast() {
entry:
%i = alloca i32, align 4
%tmp1 = bitcast i32* %i to i8*
; CHECK: call void @foo(i8* nonnull %tmp1)
call void @foo(i8* %tmp1)
ret void
}
define void @nonnullAfterSExt(i8 %a) {
entry:
%b = zext i8 %a to i32 ; <- %b is >= 0
%c = add nsw nuw i32 %b, 2 ; <- %c is > 0
%sext = sext i32 %c to i64 ; <- %sext cannot be 0 because %c is not 0
%i2p = inttoptr i64 %sext to i8* ; <- no-op int2ptr cast
; CHECK: call void @foo(i8* nonnull %i2p)
call void @foo(i8* %i2p)
ret void
}
define void @nonnullAfterZExt(i8 %a) {
entry:
%b = zext i8 %a to i32 ; <- %b is >= 0
%c = add nsw nuw i32 %b, 2 ; <- %c is > 0
%zext = zext i32 %c to i64 ; <- %zext cannot be 0 because %c is not 0
%i2p = inttoptr i64 %zext to i8* ; <- no-op int2ptr cast
; CHECK: call void @foo(i8* nonnull %i2p)
call void @foo(i8* %i2p)
ret void
}
declare void @llvm.assume(i1 %b)
define void @nonnullAfterInt2Ptr(i32 %u, i64 %lu) {
entry:
%nz = sdiv exact i32 100, %u ; %nz cannot be null
%i2p = inttoptr i32 %nz to i8* ; extending int2ptr as sizeof(i32) < sizeof(i8*)
; CHECK: call void @foo(i8* nonnull %i2p)
call void @foo(i8* %i2p)
%nz.2 = sdiv exact i64 100, %lu ; %nz.2 cannot be null
%i2p.2 = inttoptr i64 %nz.2 to i8* ; no-op int2ptr as sizeof(i64) == sizeof(i8*)
; CHECK: call void @foo(i8* nonnull %i2p.2)
call void @foo(i8* %i2p.2)
ret void
}
define void @nonnullAfterPtr2Int() {
entry:
%a = alloca i32
%p2i = ptrtoint i32* %a to i64 ; no-op ptr2int as sizeof(i32*) == sizeof(i64)
%i2p = inttoptr i64 %p2i to i8*
; CHECK: call void @foo(i8* nonnull %i2p)
call void @foo(i8* %i2p)
ret void
}
define void @maybenullAfterInt2Ptr(i128 %llu) {
entry:
%cmp = icmp ne i128 %llu, 0
call void @llvm.assume(i1 %cmp) ; %llu != 0
%i2p = inttoptr i128 %llu to i8* ; truncating int2ptr as sizeof(i128) > sizeof(i8*)
; CHECK: call void @foo(i8* %i2p)
call void @foo(i8* %i2p)
ret void
}
define void @maybenullAfterPtr2Int() {
entry:
%a = alloca i32
%p2i = ptrtoint i32* %a to i32 ; truncating ptr2int as sizeof(i32*) > sizeof(i32)
%i2p = inttoptr i32 %p2i to i8*
; CHECK: call void @foo(i8* %i2p)
call void @foo(i8* %i2p)
ret void
}
define void @maybenullAfterAddrspacecast(i8* nonnull %p) {
entry:
%addrspcast = addrspacecast i8* %p to i8 addrspace(1)*
; An address space cast can be "a no-op cast or a complex value modification,
; depending on the target and the address space pair". As a consequence, we
; cannot simply assume non-nullness of %p is preserved by the cast.
;
; CHECK: call void @bar(i8 addrspace(1)* %addrspcast)
call void @bar(i8 addrspace(1)* %addrspcast)
; CHECK: call void @foo(i8* nonnull %p)
call void @foo(i8* %p)
ret void
}
|