And another step towards transforms not introducing inttoptr and/or
ptrtoint casts that weren't there already.
As we've been establishing (see D88788/D88789), if there is a int<->ptr cast,
it basically must stay as-is, we can't do much with it.
I've looked, and the most source of new such casts being introduces,
as far as i can tell, is this transform, which, ironically,
tries to reduce count of casts..
On vanilla llvm test-suite + RawSpeed, @ `-O3`, this results in
-33.58% less `IntToPtr`s (19014 -> 12629)
and +76.20% more `PtrToInt`s (18589 -> 32753),
which is an increase of +20.69% in total.
However just on RawSpeed, where i know there are basically
none `IntToPtr` in the original source code,
this results in -99.27% less `IntToPtr`s (2724 -> 20)
and +82.92% more `PtrToInt`s (4513 -> 8255).
which is again an increase of 14.34% in total.
To me this does seem like the step in the right direction,
we end up with strictly less `IntToPtr`, but strictly more `PtrToInt`,
which seems like a reasonable trade-off.
See https://reviews.llvm.org/D88860 / https://reviews.llvm.org/D88995
for some more discussion on the subject.
(Eventually, `CastInst::isNoopCast()`/`CastInst::isEliminableCastPair`
should be taught about this, yes)
Reviewed By: nlopes, nikic
Differential Revision: https://reviews.llvm.org/D88979
As it's causing some bot failures (and per request from kbarton).
This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.
llvm-svn: 358546
Eliminate inttype phi with inttoptr/ptrtoint.
This version fixed a bug in finding the matching
phi -- the order of the incoming blocks may be
different (triggered in self build on Windows).
A new test case is added.
llvm-svn: 315272
This appears to be miscompiling Clang, as shown on two Windows bootstrap
bots:
http://lab.llvm.org:8011/builders/clang-x86-windows-msvc2015/builds/7611http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/6870
Nothing else is in the blame list. Both emit errors on this valid code
in the Windows ucrt headers:
C:\...\ucrt\malloc.h:95:32: error: invalid operands to binary expression ('char *' and 'int')
_Ptr = (char*)_Ptr + _ALLOCA_S_MARKER_SIZE;
~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~
I am attempting to reproduce this now.
This reverts r315044
llvm-svn: 315108
And follow-up r314585.
Leads to segfaults. I'll forward reproduction instructions to the patch
author.
Also, for a recommit, still add the original patch description.
Otherwise, it becomes really tedious to find out what a patch actually
does. The fact that it is a recommit with a fix is somewhat secondary.
llvm-svn: 314622
This patch will eliminate redundant intptr/ptrtoint that pessimizes
analyses such as SCEV, AA and will make optimization passes such
as auto-vectorization more powerful.
Differential revision: http://reviews.llvm.org/D37832
llvm-svn: 314561