14 Commits

Author SHA1 Message Date
Roman Lebedev
544a6aa267
[InstCombine] combineLoadToOperationType(): don't fold int<->ptr cast into load
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
2020-10-11 20:24:28 +03:00
Roman Lebedev
bef27e50b9
[NFC][InstCombine] Autogenerate a few tests being affected by upcoming patch 2020-10-07 19:00:08 +03:00
Jonathan Roelofs
7c5d2bec76 [llvm] Fix missing FileCheck directive colons
https://reviews.llvm.org/D77352
2020-04-06 09:59:08 -06:00
Eric Christopher
cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher
a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Xinliang David Li
4cdc9dab0a Renable r314928
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
2017-10-10 05:07:54 +00:00
Reid Kleckner
b6b210e61f Revert "Roll forward r314928"
This appears to be miscompiling Clang, as shown on two Windows bootstrap
bots:
http://lab.llvm.org:8011/builders/clang-x86-windows-msvc2015/builds/7611
http://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
2017-10-06 21:17:51 +00:00
Xinliang David Li
bcd36f7c5a Roll forward r314928
Fixed ThinLTO bootstrap failure : track new
bitcast per incomingVal. Added new tests.

llvm-svn: 315044
2017-10-06 05:15:25 +00:00
Xinliang David Li
04ab11a08a Revert r314928 to investigate thinLTO bootstrap failure
llvm-svn: 314961
2017-10-05 01:40:13 +00:00
Xinliang David Li
7a73757358 Recommit r314561 after fixing msan build failure
(trial 2) Incoming val defined by terminator instruction which
also requires bitcasts can not be handled.

llvm-svn: 314928
2017-10-04 20:17:55 +00:00
Daniel Jasper
3c9c60c727 Revert r314579: "Recommi r314561 after fixing over-debug assertion".
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
2017-10-01 09:53:53 +00:00
Xinliang David Li
3409d9c07f Recommi r314561 after fixing over-debug assertion
llvm-svn: 314579
2017-09-30 00:46:32 +00:00
Xinliang David Li
455dec098b Revert 314561 due to debug build assertion failure
llvm-svn: 314563
2017-09-29 22:30:34 +00:00
Xinliang David Li
5b9d96825b Eliminate PHI (int typed) which has only one use by intptr
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
2017-09-29 22:10:15 +00:00