Commit Graph

375 Commits

Author SHA1 Message Date
Andrew Trick
16404cc817 LFTR improvement to avoid truncation.
This is a reimplemntation of the patch originally in r186107.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186215 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-12 22:08:48 +00:00
Andrew Trick
807e6c71a8 Cleanup LFTR logic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186214 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-12 22:08:44 +00:00
Andrew Trick
7137909128 Cleanup: rename a variable to make the logic easier to follow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186213 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-12 22:08:41 +00:00
Chandler Carruth
6f0ec20e8f Revert "indvars: Improve LFTR by eliminating truncation when comparing
against a constant."

This reverts commit r186107. It didn't handle wrapping arithmetic in the
loop correctly and thus caused the following C program to count from
0 to UINT64_MAX instead of from 0 to 255 as intended:

  #include <stdio.h>
  int main() {
    unsigned char first = 0, last = 255;
    do { printf("%d\n", first); } while (first++ != last);
  }

Full test case and instructions to reproduce with just the -indvars pass
sent to the original review thread rather than to r186107's commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186152 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-12 11:18:55 +00:00
Andrew Trick
53b28f8623 indvars: Improve LFTR by eliminating truncation when comparing against a constant.
Patch by Michele Scandale!

Adds a special handling of the case where, during the loop exit
condition rewriting, the exit value is a constant of bitwidth lower
than the type of the induction variable: instead of introducing a
trunc operation in order to match correctly the operand types, it
allows to convert the constant value to an equivalent constant,
depending on the initial value of the induction variable and the trip
count, in order have an equivalent comparison between the induction
variable and the new constant.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186107 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-11 17:08:59 +00:00
David Majnemer
5a57dbef33 IndVarSimplify: check if loop invariant expansion can trap
IndVarSimplify is willing to move divide instructions outside of their
loop bodies if they are invariant of the loop.  However, it may not be
safe to expand them if we do not know if they can trap.

Instead, check to see if it is not safe to expand the instruction and
skip the expansion.

This fixes PR16041.

Testcase by Rafael Ávila de Espíndola.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183239 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-04 17:51:58 +00:00
Arnaud A. de Grandmaison
eb9a42e8ab IndVarSimplify: do not recompute an IV value outside of the loop if :
- it is trivially known to be used inside the loop in a way that can not be optimized away
- there is no use outside of the loop which can take advantage of the computation hoisting

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177432 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 20:00:22 +00:00
Chandler Carruth
0b8c9a80f2 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00
Chandler Carruth
d04a8d4b33 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169131 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 16:50:05 +00:00
Chandler Carruth
ece6c6bb63 Revert the series of commits starting with r166578 which introduced the
getIntPtrType support for multiple address spaces via a pointer type,
and also introduced a crasher bug in the constant folder reported in
PR14233.

These commits also contained several problems that should really be
addressed before they are re-committed. I have avoided reverting various
cleanups to the DataLayout APIs that are reasonable to have moving
forward in order to reduce the amount of churn, and minimize the number
of commits that were reverted. I've also manually updated merge
conflicts and manually arranged for the getIntPtrType function to stay
in DataLayout and to be defined in a plausible way after this revert.

Thanks to Duncan for working through this exact strategy with me, and
Nick Lewycky for tracking down the really annoying crasher this
triggered. (Test case to follow in its own commit.)

After discussing with Duncan extensively, and based on a note from
Micah, I'm going to continue to back out some more of the more
problematic patches in this series in order to ensure we go into the
LLVM 3.2 branch with a reasonable story here. I'll send a note to
llvmdev explaining what's going on and why.

Summary of reverted revisions:

r166634: Fix a compiler warning with an unused variable.
r166607: Add some cleanup to the DataLayout changes requested by
         Chandler.
r166596: Revert "Back out r166591, not sure why this made it through
         since I cancelled the command. Bleh, sorry about this!
r166591: Delete a directory that wasn't supposed to be checked in yet.
r166578: Add in support for getIntPtrType to get the pointer type based
         on the address space.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167221 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 08:07:29 +00:00
Ulrich Weigand
e669c930a6 In various places throughout the code generator, there were special
checks to avoid performing compile-time arithmetic on PPCDoubleDouble.

Now that APFloat supports arithmetic on PPCDoubleDouble, those checks
are no longer needed, and we can treat the type like any other.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166958 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-29 18:35:49 +00:00
Micah Villmow
aa76e9e2cf Add in support for getIntPtrType to get the pointer type based on the address space.
This checkin also adds in some tests that utilize these paths and updates some of the
clients.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166578 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-24 15:52:52 +00:00
Benjamin Kramer
7182126b0f Indvars: Don't recursively delete instruction during BB iteration.
This can invalidate the iterators leading to use after frees and crashes.
Fixes PR12536.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166291 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-19 17:53:54 +00:00
Micah Villmow
3574eca1b0 Move TargetData to DataLayout.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165402 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-08 16:38:25 +00:00
Jakub Staszak
eb51e95e61 Add a comment to the commit r165187.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165238 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-04 19:08:30 +00:00
Jakub Staszak
395c1502a7 Fix PR13967.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165187 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-03 23:59:47 +00:00
Benjamin Kramer
8e0d1c03ca Make MemoryBuiltins aware of TargetLibraryInfo.
This disables malloc-specific optimization when -fno-builtin (or -ffreestanding)
is specified. This has been a problem for a long time but became more severe
with the recent memory builtin improvements.

Since the memory builtin functions are used everywhere, this required passing
TLI in many places. This means that functions that now have an optional TLI
argument, like RecursivelyDeleteTriviallyDeadFunctions, won't remove dead
mallocs anymore if the TLI argument is missing. I've updated most passes to do
the right thing.

Fixes PR13694 and probably others.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162841 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-29 15:32:21 +00:00
Andrew Trick
7f496a628e indvars: drive by heuristics fix.
Minor oversight noticed by inspection. Sorry no unit test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160422 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-18 04:35:13 +00:00
Andrew Trick
4781d8ee1c indvars: Linear function test replace should avoid reusing undef.
Fixes PR13371: indvars pass incorrectly substitutes 'undef' values.

I do not like this fix. It's needed until/unless the meaning of undef
changes. It attempts to be complete according to the IR spec, but I
don't have much confidence in the implementation given the difficulty
testing undefined behavior. Worse, this invalidates some of my
hard-fought work on indvars and LSR to optimize pointer induction
variables. It results benchmark regressions, which I'll track
internally. On x86_64 no LTO I see:

-3% huffbench
-3% 400.perlbench
-8% fhourstones

My only suggestion for recovering is to change the meaning of
undef. If we could trust an arbitrary instruction to produce a some
real value that can be manipulated (e.g. incremented) according to
non-undef rules, then this case could be easily handled with SCEV.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160421 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-18 04:35:10 +00:00
Andrew Trick
c5480c634c More IndVarSimplify cleanup.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153362 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-24 00:51:17 +00:00
Andrew Trick
db0d666578 Remove -enable-iv-rewrite, which has been unsupported since 3.0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153260 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-22 17:10:11 +00:00
Andrew Trick
75ae20366f LSR fix: Add isSimplifiedLoopNest to IVUsers analysis.
Only record IVUsers that are dominated by simplified loop
headers. Otherwise SCEVExpander will crash while looking for a
preheader.

I previously tried to work around this in LSR itself, but that was
insufficient. This way, LSR can continue to run if some uses are not
in simple loops, as long as we don't attempt to analyze those users.

Fixes <rdar://problem/11049788> Segmentation fault: 11 in LoopStrengthReduce

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152892 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-16 03:16:56 +00:00
Ahmed Charles
b0934ab7d8 Remove dead code. Improve llvm_unreachable text. Simplify some control flow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150918 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-19 11:37:01 +00:00
Nick Lewycky
5fef01db01 Fix typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149185 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-28 23:33:44 +00:00
Andrew Trick
b5c26ef9da SCEVExpander fixes. Affects LSR and indvars.
LSR has gradually been improved to more aggressively reuse existing code, particularly existing phi cycles. This exposed problems with the SCEVExpander's sloppy treatment of its insertion point. I applied some rigor to the insertion point problem that will hopefully avoid an endless bug cycle in this area. Changes:

- Always used properlyDominates to check safe code hoisting.

- The insertion point provided to SCEV is now considered a lower bound. This is usually a block terminator or the use itself. Under no cirumstance may SCEVExpander insert below this point.

- LSR is reponsible for finding a "canonical" insertion point across expansion of different expressions.

- Robust logic to determine whether IV increments are in "expanded" form and/or can be safely hoisted above some insertion point.

Fixes PR11783: SCEVExpander assert.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148535 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-20 07:41:13 +00:00
Andrew Trick
86d34100cf Indvars: guard against exponential behavior in isHighCostExpansion.
This should always be done as a matter of principal. I don't have a
case that exposes the problem. I just noticed this recently while
scanning the code and realized I meant to fix it long ago.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146438 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-12 22:46:16 +00:00
Nadav Rotem
1608769abe Add support for vectors of pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145801 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-05 06:29:09 +00:00
Andrew Trick
ecb35ece5c SCEV fix. In general, Add/Mul expressions should not inherit NSW/NUW.
This reverts r139450, fixes r139453, and adds much needed comments and a
unit test.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145367 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-29 02:16:38 +00:00
Benjamin Kramer
0861f5793a Move code into anonymous namespaces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145154 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-26 23:01:57 +00:00
Andrew Trick
d3714b60b5 Rewrite LinearFunctionTestReplace to handle pointer-type IVs.
We've been hitting asserts in this code due to the many supported
combintions of modes (iv-rewrite/no-iv-rewrite) and IV types. This
second rewrite of the code attempts to deal with these cases systematically.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143546 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-02 17:19:57 +00:00
Chandler Carruth
94dffd2bb0 Add parentheses to disambiguate the precedence of these operations and
silence -Wparentheses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143534 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-02 05:43:44 +00:00
Andrew Trick
3129da8d1a Broaden an assert to handle enable-iv-rewrite=true following r143183.
Narrowest possible fix for PR11279.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143522 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-02 00:02:45 +00:00
Andrew Trick
6f2dd7ebcf LFTR should avoid a type mismatch with null pointer IVs.
Fixes rdar://10359193 Indvar LinearFunctionTestReplace assertion


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143183 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-28 03:45:11 +00:00
Eli Friedman
8ecde6cbf8 It is not safe to sink an alloca into a stacksave/stackrestore pair, so don't do that. <rdar://problem/10352360>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143093 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-27 01:33:51 +00:00
Andrew Trick
513b1f47c1 Fix indvars randomness by removing iteration over a map.
I rewrote the algorithm a while back so it doesn't require map lookup,
but neglected to change the data structure. This was caught by
llvm-gcc self host, not because there's anything special about
llvm-gcc, but because it is the only test for nondeterminism we
currently have. Unit tests don't work well for everything; we should
always try to have a nondeterminism stress test running.

Fixes PR11133: llvm-gcc self host .o mismatch after enable-iv-rewrite=false


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142036 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-15 01:38:14 +00:00
Andrew Trick
204494149b Move replaceCongruentIVs into SCEVExapander and bias toward "expanded"
IVs.

Indvars previously chose randomly between congruent IVs. Now it will
bias the decision toward IVs that SCEVExpander likes to create. This
was not done to fix any problem, it's just a welcome side effect of
factoring code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141633 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-11 02:28:51 +00:00
Andrew Trick
909ef7db3d indvars should hoist [sz]ext because licm is not rerun.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140670 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-28 01:35:36 +00:00
Andrew Trick
b0598b14aa Reapply r139759. Disable IV rewriting by default. See PR10916.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139842 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-15 20:58:37 +00:00
Andrew Trick
effb647154 [indvars] Revert r139579 until 401.bzip -arch i386 miscompilation is fixed. PR10920.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139583 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-13 05:23:49 +00:00
Andrew Trick
dd9d758a31 Disable IV rewriting by default. See PR10916.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139579 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-13 03:23:21 +00:00
Andrew Trick
94f2c23d24 [indvars] Fix bugs in floating point IV range checks noticed by inspection.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139574 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-13 01:59:32 +00:00
Andrew Trick
f21bdf4f42 Rename -disable-iv-rewrite to -enable-iv-rewrite=false in preparation for default change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139517 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-12 18:28:44 +00:00
Andrew Trick
20151da8c3 [disable-iv-rewrite] Allow WidenIV to handle NSW/NUW operations
better.

Don't immediately give up when an add operation can't be trivially
sign/zero-extended within a loop. If it has NSW/NUW flags, generate a
new expression with sign extended (non-recurrent) operand. As before,
if SCEV says that all sign extends are loop invariant, then we can
widen the operation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139453 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-10 01:24:17 +00:00
Andrew Trick
39d7802224 Comment formatting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139375 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-09 17:35:10 +00:00
Andrew Trick
75ebc0ec20 Add -verify-indvars for imperfect SCEV trip count verification after indvars.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139169 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-06 20:20:38 +00:00
Bill Wendling
2b18881185 Don't sink landingpad instructions during ind-var simplification.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138651 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-26 20:40:15 +00:00
Bill Wendling
b05fdd6bab Use getFirstInsertionPt instead of getFirstNonPHI so that it skips to the proper
insertion place.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138473 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-24 20:28:43 +00:00
Andrew Trick
bddb7f8210 Cleanup. Make ScalarEvolution an explicit argument of the
SimplifyIndVar utility since it is required.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137202 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-10 04:22:26 +00:00
Andrew Trick
4b4bb71bcd Added a SimplifyIndVar utility to simplify induction variable users
based on ScalarEvolution without changing the induction variable phis.

This utility is the main tool of IndVarSimplifyPass, but the pass also
restructures induction variables in strange ways that are sensitive to
pass ordering. This provides a way for other loop passes to simplify
new uses of induction variables created during transformation. The
utility may be used by any pass that preserves ScalarEvolution. Soon
LoopUnroll will use it.

The net effect in this checkin is to cleanup the IndVarSimplify pass
by factoring out the SimplifyIndVar algorithm into a standalone utility.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137197 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-10 03:46:27 +00:00
Andrew Trick
06988bcf6a Made SCEV's UDiv expressions more canonical. When dividing a
recurrence, the initial values low bits can sometimes be ignored.

To take advantage of this, added FoldIVUser to IndVarSimplify to fold
an IV operand into a udiv/lshr if the operator doesn't affect the
result.

-indvars -disable-iv-rewrite now transforms

i = phi i4
i1 = i0 + 1
idx = i1 >> (2 or more)
i4 = i + 4

into

i = phi i4
idx = i0 >> ...
i4 = i + 4


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137013 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-06 07:00:37 +00:00