Commit Graph

210 Commits

Author SHA1 Message Date
Haicheng Wu 9c79f14436 [CodeGenPrepare] Fix a typo in the comment. NFC.
encode => endcode.

Differential Revision: https://reviews.llvm.org/D28866

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292438 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-18 21:12:10 +00:00
Wei Mi 1d866f19de Redo store splitting in CodeGenPrepare.
This is a succeeding patch of https://reviews.llvm.org/D22840 to address the
issue when a value to be merged into an int64 pair is in a different BB. Redoing
the store splitting in CodeGenPrepare so we can match the pattern across multiple
BBs and move some instructions into the same BB. We still keep the code in dag
combine so that we can catch cases that show up after DAG combining runs.

Differential Revision: https://reviews.llvm.org/D25914



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290365 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-22 19:44:45 +00:00
George Burgess IV 1ced44b92a [Analysis] Centralize objectsize lowering logic.
We're currently doing nearly the same thing for @llvm.objectsize in
three different places: two of them are missing checks for overflow,
and one of them could subtly break if InstCombine gets much smarter
about removing alloc sites. Seems like a good idea to not do that.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290214 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-20 23:46:36 +00:00
Jun Bum Lim 4d9c93dc3f [CodeGenPrep] Skip merging empty case blocks
This is recommit of r287553 after fixing the invalid loop info after eliminating an empty block and unit test failures in AVR and WebAssembly :

Summary: Merging an empty case block into the header block of switch could cause ISel to add COPY instructions in the header of switch, instead of the case block, if the case block is used as an incoming block of a PHI. This could potentially increase dynamic instructions, especially when the switch is in a loop. I added a test case which was reduced from the benchmark I was targetting.

Reviewers: t.p.northover, mcrosier, manmanren, wmi, joerg, davidxl

Subscribers: joerg, qcolombet, danielcdh, hfinkel, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D22696

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289988 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 20:38:39 +00:00
Sanjoy Das 0499c46012 Inline stripInvariantGroupMetadata out of existence
As a one liner function, I don't think it is pulling its weight in terms
of helping readability.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289987 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 20:29:39 +00:00
Sanjoy Das 83c8485899 Fix CodeGenPrepare::stripInvariantGroupMetadata
`dropUnknownNonDebugMetadata` takes a list of "known" metadata IDs.  The
only reason it worked at all is that `getMetadataID` returns something
unrelated -- it returns the subclass ID of the receiver (which is used
in `dyn_cast` etc.).  That does not numerically match
`LLVMContext::MD_invariant_group` and ends up dropping `invariant_group`
along with every other metadata that does not numerically match
`LLVMContext::MD_invariant_group`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289973 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 18:52:33 +00:00
Jun Bum Lim 51900e49f9 Revert "[CodeGenPrep] Skip merging empty case blocks"
This reverts commit r289951.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289960 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 17:06:14 +00:00
Jun Bum Lim 6db0eaf697 [CodeGenPrep] Skip merging empty case blocks
This is recommit of r287553 after fixing the invalid loop info after eliminating an empty block:

Summary: Merging an empty case block into the header block of switch could cause ISel to add COPY instructions in the header of switch, instead of the case block, if the case block is used as an incoming block of a PHI. This could potentially increase dynamic instructions, especially when the switch is in a loop. I added a test case which was reduced from the benchmark I was targetting.

Reviewers: t.p.northover, mcrosier, manmanren, wmi, joerg, davidxl

Subscribers: joerg, qcolombet, danielcdh, hfinkel, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D22696

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289951 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 16:03:31 +00:00
Peter Collingbourne 06115803f9 IR: Change the gep_type_iterator API to avoid always exposing the "current" type.
Instead, expose whether the current type is an array or a struct, if an array
what the upper bound is, and if a struct the struct type itself. This is
in preparation for a later change which will make PointerType derive from
Type rather than SequentialType.

Differential Revision: https://reviews.llvm.org/D26594

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288458 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-02 02:24:42 +00:00
Joerg Sonnenberger 46cc79217b Revert r287553: [CodeGenPrep] Skip merging empty case blocks
It results in assertions in lib/Analysis/BlockFrequencyInfoImpl.cpp line
670 ("Expected irreducible CFG").


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288052 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-28 18:56:54 +00:00
Justin Lebar 09220c80d3 [CodeGenPrepare] Don't sink non-cheap addrspacecasts.
Summary:
Previously, CGP would unconditionally sink addrspacecast instructions,
even going so far as to sink them into a loop.

Now we check that the cast is "cheap", as defined by TLI.

We introduce a new "is-cheap" function to TLI rather than using
isNopAddrSpaceCast because some GPU platforms want the ability to ask
for non-nop casts to be sunk.

Reviewers: arsenm, tra

Subscribers: jholewinski, wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D26923

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287591 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-21 22:49:15 +00:00
Justin Lebar 5db0e4c349 [CodeGenPrepare] Rewrite a loop in terms of llvm::none_of. NFC.
Reviewers: arsenm

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D26924

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287590 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-21 22:49:11 +00:00
Jun Bum Lim b68036c70c [CodeGenPrep] Skip merging empty case blocks
Summary: Merging an empty case block into the header block of switch could cause
ISel to add COPY instructions in the header of switch, instead of the case
block, if the case block is used as an incoming block of a PHI. This could
potentially increase dynamic instructions, especially when the switch is in a
loop. I added a test case which was reduced from the benchmark I was targetting.

Reviewers: t.p.northover, mcrosier, manmanren, wmi, davidxl

Subscribers: qcolombet, danielcdh, hfinkel, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D22696

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287553 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-21 16:47:28 +00:00
Simon Pilgrim 84d1e9104a Fix comment typos. NFC.
Identified by Pedro Giffuni in PR27636.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287490 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-20 13:47:59 +00:00
Chandler Carruth 0e7e3d2f38 Hoist check for TLI above all of the attempts to use it (including one
of which that is hidden inside a separate function call) and helpfully
before building expensive transaction infrastructure. This will avoid
crashing when running CGP in a generic mode if we ever managed to hit
this case.

Note that I spent some time looking at alternatives. CGP is actually
used without a TM or TLI in order to do some target-independent testing.
Further, all of the neighboring optimization techniques actually have
some paths that are effective even in the absence of TLI so this seemed
the correct scope at which to check and bypass logic. It still isn't
clear that long-term support for missing TM/TLI is the right
cost/benefit tradeoff for CGP -- we seem to get relatively little for it
and the code is just littered with checks (and assumptions which
I suspect are still missing some checks).

This at least fixes the potential bug in this code spotted by
PVS-Studio, so we've got that going for us. ;]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285987 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-04 06:54:00 +00:00
Dehao Chen 977fc82cac Use profile info to set function section prefix to group hot/cold functions.
Summary:
The original implementation is in r261607, which was reverted in r269726 to accomendate the ProfileSummaryInfo analysis pass. The new implementation:
1. add a new metadata for function section prefix
2. query against ProfileSummaryInfo in CGP to set the correct section prefix for each function
3. output the section prefix set by CGP

Reviewers: davidxl, eraman

Subscribers: vsk, llvm-commits

Differential Revision: https://reviews.llvm.org/D24989

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284533 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-18 20:42:47 +00:00
Andrea Di Biagio fe42b012cd [CodeGenPrepare] When moving a zext near to its associated load, do not retain the original debug location.
CodeGenPrepare knows how to move a zext of a load into the same basic block
where the load lives. The goal is to help ISel match a zero-extending load
instead of two separated instructions.

CGP attempts to move a zext computation even if it lives in a basic block that
does not post-dominate the load's basic block. That means, the hoisted zext may
be speculated. Preserving the zext location would hurt the debugging experience
and the quality of sample pgo.
With this patch, when moving a zext near to its associated load, CGP no longer
propagates the zext's debug location. Instead, CGP conservatively reuses the
same debug location for the load and the zext.

An alternative approach would be to assign an artificial line-0 location to the
zext. However we don't want to over-use the 'line-0' for this particular case
because it would have a size cost in the line-table section for no additional
benefit.

Differential Revision: https://reviews.llvm.org/D25611


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284377 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-17 11:32:26 +00:00
Wolfgang Pieb 65236ec176 Preserve the debug location when CodeGenPrepare sinks a compare instruction into the
basic block of a user.

Patch by Andrea DiBiagio.

Differential Revision: https://reviews.llvm.org/D24632



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283500 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-06 21:43:45 +00:00
Mehdi Amini 67f335d992 Use StringRef in Pass/PassManager APIs (NFC)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283004 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-01 02:56:57 +00:00
Dehao Chen 77ad09277a Fix the bug introduced in r281252.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281253 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-12 20:29:54 +00:00
Dehao Chen 8c8aa02da6 Lower consecutive select instructions correctly.
Summary: If consecutive select instructions are lowered separately in CGP, it will introduce redundant condition check and branches that cannot be removed by later optimization phases. This patch lowers all consecutive select instructions at the same to to avoid inefficent code as demonstrated in https://llvm.org/bugs/show_bug.cgi?id=29095

Reviewers: davidxl

Subscribers: vsk, llvm-commits

Differential Revision: https://reviews.llvm.org/D24147

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281252 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-12 20:23:28 +00:00
Michael Kuperstein 2a93bda6e9 [CGP] Be less conservative about tail-duplicating a ret to allow tail calls
CGP tail-duplicates rets into blocks that end with a call that feed the ret.
This puts the call in tail position, potentially allowing the DAG builder to
lower it as a tail call. To avoid tail duplication in cases where we won't
form the tail call, CGP tried to predict whether this is going to be possible,
and avoids doing it when lowering as a tail call will definitely fail.
However, it was being too conservative by always throwing away calls to
functions with a signext/zeroext attribute on the return type.

Instead, we can use the same logic the builder uses to determine whether the
attributes work out.

Differential Revision: https://reviews.llvm.org/D24315


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280894 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-08 00:48:37 +00:00
Michael Kuperstein 9c0826c800 Don't reuse a variable name in a nested scope. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280853 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-07 20:29:49 +00:00
Xinliang David Li da48846879 [Profile] preserve branch metadata lowering select in CGP
CGP currently drops select's MD_prof profile data when
generating conditional branch which can lead to bad
code layout. The patch fixes the issue.

Differential Revision: http://reviews.llvm.org/D24169


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280600 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-03 21:26:36 +00:00
David Majnemer 975248e4fb Use the range variant of find instead of unpacking begin/end
If the result of the find is only used to compare against end(), just
use is_contained instead.

No functionality change is intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278433 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-11 22:21:41 +00:00