Commit Graph

1166 Commits

Author SHA1 Message Date
Simon Pilgrim
44513da617 [X86][SSE] Float comparisons can sometimes be safely commuted
For ordered, unordered, equal and not-equal tests, packed float and double comparison instructions can be safely commuted without affecting the results. This patch checks the comparison mode of the (v)cmpps + (v)cmppd instructions and commutes the result if it can.

Differential Revision: http://reviews.llvm.org/D7178

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227145 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 22:29:24 +00:00
Simon Pilgrim
3ba85ab23a [X86][PCLMUL] Enable commutation for PCLMUL instructions
Patch to allow (v)pclmulqdq to be commuted - swaps the src registers and inverts the immediate (low/high) src mask.

Differential Revision: http://reviews.llvm.org/D7180

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227141 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 22:00:18 +00:00
Sanjay Patel
956d6f0cf5 Model sqrtsd as a binary operation with one source operand tied to the destination (PR14221)
This patch fixes the following miscompile:

define void @sqrtsd(<2 x double> %a) nounwind uwtable ssp {
  %0 = tail call <2 x double> @llvm.x86.sse2.sqrt.sd(<2 x double> %a) nounwind 
  %a0 = extractelement <2 x double> %0, i32 0
  %conv = fptrunc double %a0 to float
  %a1 = extractelement <2 x double> %0, i32 1
  %conv3 = fptrunc double %a1 to float
  tail call void @callee2(float %conv, float %conv3) nounwind
  ret void
}

Current codegen:

sqrtsd	%xmm0, %xmm1        ## high element of %xmm1 is undef here
xorps	%xmm0, %xmm0
cvtsd2ss	%xmm1, %xmm0
shufpd	$1, %xmm1, %xmm1
cvtsd2ss	%xmm1, %xmm1 ## operating on undef value
jmp	_callee

This is a continuation of http://llvm.org/viewvc/llvm-project?view=revision&revision=224624 ( http://reviews.llvm.org/D6330 ) 
which was itself a continuation of r167064 ( http://llvm.org/viewvc/llvm-project?view=revision&revision=167064 ).

All of these patches are partial fixes for PR14221 ( http://llvm.org/bugs/show_bug.cgi?id=14221 ); 
this should be the final patch needed to resolve that bug.

Differential Revision: http://reviews.llvm.org/D6885



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227111 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 18:42:16 +00:00
Craig Topper
ff763041d2 [X86] Give scalar VRNDSCALE instructions priority in AVX512 mode.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227039 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-25 08:49:22 +00:00
Craig Topper
e237954ed8 Remove tab characters. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227036 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-25 08:45:32 +00:00
Craig Topper
896c1e9b70 [X86] Replace i32i8imm on SSE/AVX instructions with i32u8imm which will make the assembler bounds check them. It will also make them print as unsigned.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227032 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-25 02:21:16 +00:00
Craig Topper
046047ccc3 [X86] Use u8imm in several places that used i32i8imm that don't require an i32 type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227031 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-25 02:21:13 +00:00
Craig Topper
a92d03bb7a Remove tab characters. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227030 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-25 02:21:11 +00:00
Simon Pilgrim
4269590166 [X86][SSE] Added support for SSE3 lane duplication shuffle instructions
This patch adds shuffle matching for the SSE3 MOVDDUP, MOVSLDUP and MOVSHDUP instructions. The big use of these being that they avoid many single source shuffles from needing to use (pre-AVX) dual source instructions such as SHUFPD/SHUFPS: causing extra moves and preventing load folds.

Adding these instructions uncovered an issue in XFormVExtractWithShuffleIntoLoad which crashed on single operand shuffle instructions (now fixed). It also involved fixing getTargetShuffleMask to correctly identify theses instructions as unary shuffles.

Also adds a missing tablegen pattern for MOVDDUP.

Differential Revision: http://reviews.llvm.org/D7042



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226716 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-21 22:44:35 +00:00
Ahmed Bougacha
34288d885e [X86] Declare SSE4.1/AVX2 vector extloads covered by PMOV[SZ]X legal.
Now that we can fully specify extload legality, we can declare them
legal for the PMOVSX/PMOVZX instructions.  This for instance enables
a DAGCombine to fire on code such as
  (and (<zextload-equivalent> ...), <redundant mask>)
to turn it into:
  (zextload ...)
as seen in the testcase changes.

There is one regression, in widen_load-2.ll: we're no longer able
to do store-to-load forwarding with illegal extload memory types.
This will be addressed separately.

Differential Revision: http://reviews.llvm.org/D6533


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226676 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-21 17:07:06 +00:00
Craig Topper
951d088ae7 [X86] Convert all the i8imm used by SSE and AVX instructions to u8imm.
This makes the assembler check their size and removes a hack from the disassembler to avoid sign extending the immediate.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226645 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-21 08:15:54 +00:00
Craig Topper
f81b1f346a [x86] Add assembly parser bounds checking to the immediate value for cmpss/cmpsd/cmpps/cmppd.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226642 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-21 06:07:53 +00:00
Craig Topper
d624796bc6 [x86] Add some mayLoad/hasSideEffects flags. Remove one that was already covered by a pattern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226562 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-20 12:15:30 +00:00
Simon Pilgrim
dc5a2dabfe [X86][SSE] Minor fix to VPBLENDW AVX2 commutation.
D6015 / rL221313 enabled commutation for SSE immediate blend instructions, but due to a typo the AVX2 VPBLENDW ymm instructions weren't flagged as commutative along with the others in the tables, but were still being commuted in code and tested for.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225612 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-11 22:08:01 +00:00
Craig Topper
6ba84e58da [x86] Prevent llvm.x86.cmp.ps/pd/ss/sd from being selected with bad immediates. The frontend now checks this when the builtin is used. This will allow the instruction printer to not have to deal with invalid immediates on these instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224885 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-27 18:10:56 +00:00
Elena Demikhovsky
573b762b68 Masked load and store codegen - fixed 128-bit vectors
The codegen failed on 128-bit types on AVX2.
I added patterns and in td files and tests.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224647 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 23:27:57 +00:00
Sanjay Patel
9ccbf1a260 Model sqrtss as a binary operation with one source operand tied to the destination (PR14221)
This is a continuation of r167064 ( http://llvm.org/viewvc/llvm-project?view=revision&revision=167064 ).
That patch started to fix PR14221 ( http://llvm.org/bugs/show_bug.cgi?id=14221 ), but it was not completed. 

Differential Revision: http://reviews.llvm.org/D6330



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224624 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 22:16:28 +00:00
Robert Khasanov
d25d7bb372 [AVX512] Enable FP arithmetic lowering for AVX512VL subsets.
Added RegOp2MemOpTable4 to transform 4th operand from register to memory in merge-masked versions of instructions. 
Added lowering tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224516 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-18 12:28:22 +00:00
Craig Topper
4ae31b7e7d [X86] Don't use PS prefix on LDMXCSR/STMXCSR.
Near as I can tell prefixes are ignored on these instructions except for a comment in the Intel docs about 0xf3. Binutils disassembler seems to ignore prefixes on these instructions. Our disassembler still doesn't distinguish PS and "no prefix" well enough for this to make a functional change, but it helps with experiments I'm doing on a potential new disassembler table builder.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224496 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-18 05:02:10 +00:00
Robert Khasanov
41100285aa [AVX512] Enable integer arithmetic lowering for AVX512BW/VL subsets.
Added lowering tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224349 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-16 18:24:07 +00:00
Sanjay Patel
8fe9488a40 combine consecutive subvector 16-byte loads into one 32-byte load
This is a fix for PR21709 ( http://llvm.org/bugs/show_bug.cgi?id=21709 ).
When we have 2 consecutive 16-byte loads that are merged into one 32-byte vector,
we can use a single 32-byte load instead. 
But we don't do this for SandyBridge / IvyBridge because they have slower 32-byte memops.
We also don't bother using 32-byte *integer* loads on a machine that only has AVX1 (btver2)
because those operands would have to be split in half anyway since there is no support for
32-byte integer math ops.

Differential Revision: http://reviews.llvm.org/D6492



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224344 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-16 16:30:01 +00:00
Robert Khasanov
5dc8ac87f1 [AVX512] Enabling bit logic lowering
Added lowering tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224132 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-12 17:02:18 +00:00
Robert Khasanov
a4f5a5525d [AVX512] Enabling MIN/MAX lowering.
Added lowering tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224127 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-12 15:10:43 +00:00
Ahmed Bougacha
11fcb48306 [X86] Add a temporary testcase for PR21876/r223996.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224074 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-11 23:07:52 +00:00
Ahmed Bougacha
0aac0703f8 [X86] Add back AVX2 VR256 PMOVX patterns.
We can't reach those from zext, but other parts of the backend (the shuffle
lowering) generate 256-bit VZEXT nodes.

Fixes PR21876.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223996 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-11 04:32:17 +00:00
Sanjay Patel
3cd5b83bb8 Match new shuffle codegen for MOVHPD patterns
Add patterns to match SSE (shufpd) and AVX (vpermilpd) shuffle codegen
when storing the high element of a v2f64. The existing patterns were
only checking for an unpckh type of shuffle. 

http://llvm.org/bugs/show_bug.cgi?id=21791

Differential Revision: http://reviews.llvm.org/D6586



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223929 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-10 16:58:54 +00:00
Ahmed Bougacha
3b9ac8c7c3 [X86] Refactor PMOV[SZ]Xrm to add missing AVX2 patterns.
Most patterns will go away once the extload legalization changes land.

Differential Revision: http://reviews.llvm.org/D6125


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223567 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-06 01:31:07 +00:00
Elena Demikhovsky
73ae1df82c Masked Load / Store Intrinsics - the CodeGen part.
I'm recommiting the codegen part of the patch.
The vectorizer part will be send to review again.

Masked Vector Load and Store Intrinsics.
Introduced new target-independent intrinsics in order to support masked vector loads and stores. The loop vectorizer optimizes loops containing conditional memory accesses by generating these intrinsics for existing targets AVX2 and AVX-512. The vectorizer asks the target about availability of masked vector loads and stores.
Added SDNodes for masked operations and lowering patterns for X86 code generator.
Examples:
<16 x i32> @llvm.masked.load.v16i32(i8* %addr, <16 x i32> %passthru, i32 4 /* align */, <16 x i1> %mask)
declare void @llvm.masked.store.v8f64(i8* %addr, <8 x double> %value, i32 4, <8 x i1> %mask)

Scalarizer for other targets (not AVX2/AVX-512) will be done in a separate patch.

http://reviews.llvm.org/D6191



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223348 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-04 09:40:44 +00:00
Michael Liao
d3c452a506 [X86] Clean up whitespace as well as minor coding style
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223339 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-04 05:20:33 +00:00
Simon Pilgrim
ec49b722fd [X86][SSE] Keep 4i32 vector insertions in integer domain on SSE4.1 targets
4i32 shuffles for single insertions into zero vectors lowers to X86vzmovl which was using (v)blendps - causing domain switch stalls. This patch fixes this by using (v)pblendw instead.

The updated tests on test/CodeGen/X86/sse41.ll still contain a domain stall due to the use of insertps - I'm looking at fixing this in a future patch.

Differential Revision: http://reviews.llvm.org/D6458



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223165 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-02 22:31:23 +00:00
Duncan P. N. Exon Smith
54786a0936 Revert "Masked Vector Load and Store Intrinsics."
This reverts commit r222632 (and follow-up r222636), which caused a host
of LNT failures on an internal bot.  I'll respond to the commit on the
list with a reproduction of one of the failures.

Conflicts:
	lib/Target/X86/X86TargetTransformInfo.cpp

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222936 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-28 21:29:14 +00:00
Craig Topper
c0dae440e6 Replace neverHasSideEffects=1 with hasSideEffects=0 in all .td files.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222801 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-26 00:46:26 +00:00
Elena Demikhovsky
ae1ae2c3a1 Masked Vector Load and Store Intrinsics.
Introduced new target-independent intrinsics in order to support masked vector loads and stores. The loop vectorizer optimizes loops containing conditional memory accesses by generating these intrinsics for existing targets AVX2 and AVX-512. The vectorizer asks the target about availability of masked vector loads and stores.
Added SDNodes for masked operations and lowering patterns for X86 code generator.
Examples:
<16 x i32> @llvm.masked.load.v16i32(i8* %addr, <16 x i32> %passthru, i32 4 /* align */, <16 x i1> %mask)
declare void @llvm.masked.store.v8f64(i8* %addr, <8 x double> %value, i32 4, <8 x i1> %mask)

Scalarizer for other targets (not AVX2/AVX-512) will be done in a separate patch.

http://reviews.llvm.org/D6191



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222632 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-23 08:07:43 +00:00
Simon Pilgrim
4ad0654bb4 [X86][SSE] Enable commutation for SSE immediate blend instructions
Patch to allow (v)blendps, (v)blendpd, (v)pblendw and vpblendd instructions to be commuted - swaps the src registers and inverts the blend mask.

This is primarily to improve memory folding (see new tests), but it also improves the quality of shuffles (see modified tests).

Differential Revision: http://reviews.llvm.org/D6015



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221313 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-04 23:25:08 +00:00
Andrea Di Biagio
5512b50db5 [X86] Fix missed selection of non-temporal store of zero vector.
When the input to a store instruction was a zero vector, the backend
always selected a normal vector store regardless of the non-temporal
hint. This is fixed by this patch.

This fixes PR19370.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220054 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-17 17:27:06 +00:00
Benjamin Kramer
043994e266 X86: Drop the isConvertibleTo3Addr bit from shufps/shufpd now that we don't convert them anymore.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219112 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-06 09:56:40 +00:00
Chandler Carruth
f159de96bd [x86] Add a really preposterous number of patterns for matching all of
the various ways in which blends can be used to do vector element
insertion for lowering with the scalar math instruction forms that
effectively re-blend with the high elements after performing the
operation.

This then allows me to bail on the element insertion lowering path when
we have SSE4.1 and are going to be doing a normal blend, which in turn
restores the last of the blends lost from the new vector shuffle
lowering when I got it to prioritize insertion in other cases (for
example when we don't *have* a blend instruction).

Without the patterns, using blends here would have regressed
sse-scalar-fp-arith.ll *completely* with the new vector shuffle
lowering. For completeness, I've added RUN-lines with the new lowering
here. This is somewhat superfluous as I'm about to flip the default, but
hey, it shows that this actually significantly changed behavior.

The patterns I've added are just ridiculously repetative. Suggestions on
making them better very much welcome. In particular, handling the
commuted form of the v2f64 patterns is somewhat obnoxious.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219033 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 22:43:17 +00:00
Chandler Carruth
91ea3e41ae [x86] Adjust the patterns for lowering X86vzmovl nodes which don't
perform a load to use blendps rather than movss when it is available.

For non-loads, blendps is *much* faster. It can execute on two ports in
Sandy Bridge and Ivy Bridge, and *three* ports on Haswell. This fixes
one of the "regressions" from aggressively taking the "insertion" path
in the new vector shuffle lowering.

This does highlight one problem with blendps -- it isn't commuted as
heavily as it should be. That's future work though.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219022 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 21:38:49 +00:00
Chandler Carruth
dce98e6739 [x86] Teach the new vector shuffle lowering to aggressively form MOVSS
and MOVSD nodes for single element vector inserts.

This is particularly important because a number of patterns in the
backend detect these patterns and leverage them to simplify things. It
also fixes quite a few of the insertion bad code examples. However, it
regresses a specific area: when available, blendps and blendpd are
*dramatically* faster than movss and movsd respectively. But it doesn't
really work to form the blend logic first because the blends *aren't* as
crazy efficient when the data is coming from memory anyways, and thus
will have a movss or movsd regardless. Also, doing that would block
a bunch of the patterns that this is designed to hit.

So my plan is to go into the patterns for lowering MOVSS and MOVSD and
lower them via blends when available. However that's a pretty invasive
restructuring so it will need to be a follow-up patch.

I have already gone into the patterns to lower MOVSS and MOVSD from
memory using MOVLPD, etc. Without that, several of the test cases
I already have regress.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218985 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 13:11:13 +00:00
Chandler Carruth
bf21d40070 [x86] Teach the new vector shuffle lowering to widen floating point
elements as well as integer elements in order to form simpler shuffle
patterns.

This is the primary reason why we were failing to match some of the
2-and-2 floating point shuffles such as PR21140. Even after fixing this
we need to support some extra patterns in the backend in order to match
the resulting X86ISD::UNPCKL nodes into the correct instructions. This
commit should fix PR21140 and includes more comprehensive testing of
insertion patterns in v4 shuffles.

Not all of the added tests are beautiful. For example, we don't have
clever instructions to insert-via-load in the integer domain. There are
also some places where we aren't sufficiently cunning with our use of
movq and movd, but that's future work.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218911 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 21:37:14 +00:00
Chandler Carruth
afe75172b1 [x86] Teach the new vector shuffle lowering about VBROADCAST and
VPBROADCAST.

This has the somewhat expected pervasive impact. I don't know why
I forgot about this. Everything seems good with lots of significant
improvements in the tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218724 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 00:41:21 +00:00
Andrea Di Biagio
a5ab9baf83 [X86][SchedModel] SSE reciprocal square root instruction latencies.
The SSE rsqrt instruction (a fast reciprocal square root estimate) was
grouped in the same scheduling IIC_SSE_SQRT* class as the accurate (but very
slow) SSE sqrt instruction. For code which uses rsqrt (possibly with
newton-raphson iterations) this poor scheduling was affecting performances.

This patch splits off the rsqrt instruction from the sqrt instruction scheduling
classes and creates new IIC_SSE_RSQER* classes with latency values based on
Agner's table.

Differential Revision: http://reviews.llvm.org/D5370

Patch by Simon Pilgrim.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218517 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 12:56:44 +00:00
Robert Khasanov
26ba182fdf [AVX512] Added load/store from BW/VL subsets to Register2Memory opcode tables.
Added lowering tests for these instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218508 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 09:48:50 +00:00
Akira Hatanaka
0253523c92 [X86,AVX] Add an isel pattern for X86VBroadcast.
This fixes PR21050 and rdar://problem/18434607.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218431 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 00:26:15 +00:00
Chandler Carruth
8f637786d8 [x86] Teach the AVX1 path of the new vector shuffle lowering one more
trick that I missed.

VPERMILPS has a non-immediate memory operand mode that allows it to do
asymetric shuffles in the two 128-bit lanes. Use this rather than two
shuffles and a blend.

However, it turns out the variable shuffle path to VPERMILPS (and
VPERMILPD, although that one offers no functional differenc from the
immediate operand other than variability) wasn't even plumbed through
codegen. Do such plumbing so that we can reasonably emit
a variable-masked VPERMILP instruction. Also plumb basic comment parsing
and printing through so that the tests are reasonable.

There are still a few tests which don't show the shuffle pattern. These
are tests with undef lanes. I'll teach the shuffle decoding and printing
to handle undef mask entries in a follow-up. I've looked at the masks
and they seem reasonable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218300 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-23 10:08:29 +00:00
Chandler Carruth
4b365159bf [x86] Rename X86ISD::VPERMILP to X86ISD::VPERMILPI (and the same for the
td pattern). Currently we only model the immediate operand variation of
VPERMILPS and VPERMILPD, we should make that clear in the pseudos used.
Will be adding support for the variable mask variant in my next commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218282 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-22 22:29:42 +00:00
Sanjay Patel
6539887847 Use broadcasts to optimize overall size when loading constant splat vectors (x86-64 with AVX or AVX2).
We generate broadcast instructions on CPUs with AVX2 to load some constant splat vectors.
This patch should preserve all existing behavior with regular optimization levels, 
but also use splats whenever possible when optimizing for *size* on any CPU with AVX or AVX2.

The tradeoff is up to 5 extra instruction bytes for the broadcast instruction to save
at least 8 bytes (up to 31 bytes) of constant pool data.

Differential Revision: http://reviews.llvm.org/D5347



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218263 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-22 18:54:01 +00:00
Chandler Carruth
2e363ece75 [x86] Remove the last vestiges of the BLENDI-based ADDSUB pattern
matching. This design just fundamentally didn't work because ADDSUB is
available prior to any legal lowerings of BLENDI nodes. Instead, we have
a dedicated ADDSUB synthetic ISD node which is pattern matched trivially
into the instructions. These nodes are then recognized by both the
existing and a trivial new lowering combine in the backend. Removing
these patterns required adding 2 missing shuffle masks to the DAG
combine, without which tests would have failed. Added the masks and
a helpful assert as well to catch if anything ever goes wrong here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217851 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-16 00:39:08 +00:00
Chandler Carruth
fa6cf7e73c [x86] Start fixing our emission of ADDSUBPS and ADDSUBPD instructions by
introducing a synthetic X86 ISD node representing this generic
operation.

The relevant patterns for mapping these nodes into the concrete
instructions are also added, and a gnarly bit of C++ code in the
target-specific DAG combiner is replaced with simple code emitting this
primitive.

The next step is to generically combine blends of adds and subs into
this node so that we can drop the reliance on an SSE4.1 ISD node
(BLENDI) when matching an SSE3 feature (ADDSUB).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217819 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-15 20:09:47 +00:00
Chandler Carruth
7cd7154421 [x86] Fix a pretty horrible bug and inconsistency in the x86 asm
parsing (and latent bug in the instruction definitions).

This is effectively a revert of r136287 which tried to address
a specific and narrow case of immediate operands failing to be accepted
by x86 instructions with a pretty heavy hammer: it introduced a new kind
of operand that behaved differently. All of that is removed with this
commit, but the test cases are both preserved and enhanced.

The core problem that r136287 and this commit are trying to handle is
that gas accepts both of the following instructions:

  insertps $192, %xmm0, %xmm1
  insertps $-64, %xmm0, %xmm1

These will encode to the same byte sequence, with the immediate
occupying an 8-bit entry. The first form was fixed by r136287 but that
broke the prior handling of the second form! =[ Ironically, we would
still emit the second form in some cases and then be unable to
re-assemble the output.

The reason why the first instruction failed to be handled is because
prior to r136287 the operands ere marked 'i32i8imm' which forces them to
be sign-extenable. Clearly, that won't work for 192 in a single byte.
However, making thim zero-extended or "unsigned" doesn't really address
the core issue either because it breaks negative immediates. The correct
fix is to make these operands 'i8imm' reflecting that they can be either
signed or unsigned but must be 8-bit immediates. This patch backs out
r136287 and then changes those places as well as some others to use
'i8imm' rather than one of the extended variants.

Naturally, this broke something else. The custom DAG nodes had to be
updated to have a much more accurate type constraint of an i8 node, and
a bunch of Pat immediates needed to be specified as i8 values.

The fallout didn't end there though. We also then ceased to be able to
match the instruction-specific intrinsics to the instructions so
modified. Digging, this is because they too used i32 rather than i8 in
their signature. So I've also switched those intrinsics to i8 arguments
in line with the instructions.

In order to make the intrinsic adjustments of course, I also had to add
auto upgrading for the intrinsics.

I suspect that the intrinsic argument types may have led everything down
this rabbit hole. Pretty happy with the result.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217310 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-06 10:00:01 +00:00