Sometimes pointers are casted to ULONG just to get an ID or tag - this
is fine for 32bit pointers, but 64bit pointers will truncate which might
result in not being so unique after all.
CRC-ing the pointer should yield a more likely to be unique 32bit value.
NULL is a special case that yields 0 instead of the CRC, so code that
handles IDs/Tags with value 0 differently will continue to work.
For 32bit builds, it just returns the pointer as ULONG.
turns out that using UINTPTR_MAX is a pain on several systems like
FreeBSD or even older Linux/glibc systems, so maybe let's not do that
anymore.
Now I check for known CPU-architectures instead.
I also added some sanity checks to make sure the detection was
correct.
The code used to store the world pointer as a console variable
"pwoCurrentWorld" of type INDEX (int32) - that won't work for 64bit, so
I added CShell::SetCurrentWorld() and CShell::GetCurrentWorld() and
store it as a pointer.
introduced PLATFORM_32BIT and PLATFORM_64BIT macros, so you can do
#ifdef PLATFORM_64BIT if you need to.
I needed that for CDrawPort::GetID() to properly CRC a pointer.
Also added a sanity check in Engine/Base/Types.h that makes sure that
uintprt_t and size_t have the same size, as the code uses size_t to
store pointers (or cast from pointer to int) all over the place.
Made some "tags" from Engine/Templates/BSP_internal.h size_t instead of
ULONG - they're used to store pointers to identify vertices and such,
so they'd better be big enough to actually store a pointer.
Some more are still missing.
* FloatToInt() should now round correctly ot nearest, even for
negative numbers
* Log2() now calls log2f() instead of log10()*3.321 - no idea what the
previous code was about, I doubt it's faster (and the ASM code uses
something like log2, too).
* FastLog2() (for integers) now uses __builtin_clz() when building with
GCC/clang - the resulting ASM should be pretty similar to the inline
ASM below. I wonder why that function takes signed ints, log2(-1) in
reality is an irrational number (but the function returns 31)..
Also, both the inline ASM and my version return 0 for Log2(0), but
INT_MIN would be closer to the truth
* commented out FastMaxLog2(), it's unused.
* implemented _rotl() using a fast(er) trick from
http://blog.regehr.org/archives/1063
Touches a lot of code to remove long constants like "1L", so this patch is
large and ugly, but I think it makes all those Clamp() calls look nicer in
the long run.
Most of the game is 64-bit clean, since we can build without assembly code
now. I've marked the things that are obviously still wrong with STUBBED lines.
That being said: a 64-bit build can already run the demos mostly correctly,
so we're actually almost there!
There are a few obvious things that are obviously wrong, to be fixed.
I think this is a leftover from the mmap()-like code that used to be
in the engine, but now it's a lot of complexity to basically test this:
- Was this a memory access violation?
- If no, crash.
- If yes:
- Was it part of a CTStream?
- If no, crash.
- If yes, crash.
Instead, let's just crash. :)
(If I'm misunderstanding this, just roll back from revision control.)
