Thanks. That makes sense to me, and it fits in with something that
U.Matlu suggested. The following is my reply to U.Matlu's most recent
post on this:
Thanks for the link. The following is my (limited) understanding of the terms:
* HOST_WIDE_INT, unsigned HOST_WIDE_INT are the largest fixed size integers
available on the computing platform in question; HOST_BITS_PER_WIDE_INT has
the number of bits of those fixed size integers.
* "wide int" (and functions associated with it) is an implementation of integers
which in a particular instance (probably) has a fixed number of bits, but
that number of bits can be arbitrarily larger than HOST_BITS_PER_WIDE_INT.
It seems plausible that all these are as you say mostly used internally in the
"GCC Middle and Back End API". Maybe my hope of using "#include" is impossible?
I have used "wide int" in the past by putting a "hook" in choose_multiplier in
expmed.c so that when a GCC make runs choose_multiplier to test it, instead of
running the tests the GCC make runs some "wide int" code that I want to try out.
I can still run some code from 2018-02-12-t-15:26:27 by copying an expmed.c
replacement over the original GCC.7.3.0 expmed.c, and using a GCC make which
skips unchanged files and starts with the first changed file, that is expmed.c.
But changing that expmed.c's modification date (even with no changes to it)
stops that method working. I've tried reinstalling GCC, copying the "hooked"
expmed.c over the existing expmed.c, and then using make, but that fails before
running the "hooked" code. I'm now completely at a loss as to how to progress.
I hope the above makes some sort of sense, and thanks again for your help.
On 7/11/18, Martin Sebor <msebor@xxxxxxxxx> wrote:
> On 07/11/2018 06:01 AM, colinb2 . wrote:
>> Thanks to the two quick responders: I wasn't anticipating such immediate
>> help.
>>
>> I've looked in gccint.pdf, and I was hoping to find but couldn't something
>> like:
>> #include <stdlib.h>
>>
>> If it helps, "wide int" is used in function "choose_multiplier" in
>> expmed.c
>> which is located here for example: gcc-7.3.0/gcc/expmed.c
>>
>> I've only ever managed to use "wide int" by making GCC and inserting a
>> "hook"
>> in "choose_multiplier" which runs some tests and benchmarks comparing
>> using
>> "wide int" with using fixed width integers "unsigned HOST_WIDE_INT".
>> I was hoping there was an easier way to do it!
>
> The wide int classes aren't meant to be used outside GCC itself.
> They are defined in wide-int.{h,cc} with formatted output support
> in wide-int-print.{h,cc}. AFAICT, the .o files are only linked
> into libbackend.a.
>
> Martin
>
>
>
