llvm-gcc unable to handle NOT operation

[llvmbot]

Bugzilla Link	1346
Resolution	FIXED
Resolved on	Feb 22, 2010 12:49
Version	trunk
OS	MacOS X
Reporter	LLVM Bugzilla Contributor

Extended Description

--- r.c ---
extern bar(void *);

void f(void *cd) {
bar(((void *)((unsigned long)(cd) ^ -1)));
}

$ llvm-gcc /tmp/r.c -c
/tmp/r.c: In function ‘f’:
/tmp/r.c:4: internal compiler error: Bus error
Please submit a full bug report,
with preprocessed source if appropriate.
See URL:http://llvm.org/bugs for instructions

$

[llvmbot]

This occurs because, for some strange reason, the gcc argument type
is a void*. BinaryOperator::createNot does this:
AllOnes = ConstantInt::getAllOnesValue(Op->getType());
which returns NULL for an i8*. Probably it should assert. This NULL
causes the later segmentation fault.

[lattner]

Yuck. Okay, this should be straight-forward to fix: the codepath for not should do something like
EmitBinOp does: if it detects a pointer operand, it calls EmitPtrBitOp, which casts the operands to integer
types, does the operation, then casts back.

Do you want to tackle this?

-Chris

[llvmbot]

We just want to cast poniter to int so,

if (isa(Op->getType()))
Op = CastToType(Instruction::PtrToInt, Op, TREE_TYPE(exp));

is sufficient. No ?

[lattner]

if TREE_TYPE(exp) is an integer type, then yep!

-Chris

[lattner]

This is fixed, right?

[llvmbot]

Yup.

http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070423/048356.html