Summary:
1. Enable infrastructure of AVX512_BF16, which is supported for BFLOAT16 in Cooper Lake;
2. Enable VCVTNE2PS2BF16, VCVTNEPS2BF16 and DPBF16PS instructions, which are Vector Neural Network Instructions supporting BFLOAT16 inputs and conversion instructions from IEEE single precision.
VCVTNE2PS2BF16: Convert Two Packed Single Data to One Packed BF16 Data.
VCVTNEPS2BF16: Convert Packed Single Data to Packed BF16 Data.
VDPBF16PS: Dot Product of BF16 Pairs Accumulated into Packed Single Precision.
For more details about BF16 isa, please refer to the latest ISE document: https://software.intel.com/en-us/download/intel-architecture-instruction-set-extensions-programming-reference
Author: LiuTianle
Reviewers: craig.topper, smaslov, LuoYuanke, wxiao3, annita.zhang, RKSimon, spatel
Reviewed By: craig.topper
Subscribers: kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60550
llvm-svn: 360017
Summary:
Previously we would use MOVZXrm8/MOVZXrm16, but those are longer encodings.
This is similar to what we do in the loadi32 predicate.
Reviewers: RKSimon, spatel
Reviewed By: RKSimon
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60341
llvm-svn: 357875
Summary:
Reorder the condition code enum to match their encodings. Move it to MC layer so it can be used by the scheduler models.
This avoids needing an isel pattern for each condition code. And it removes
translation switches for converting between CMOV instructions and condition
codes.
Now the printer, encoder and disassembler take care of converting the immediate.
We use InstAliases to handle the assembly matching. But we print using the
asm string in the instruction definition. The instruction itself is marked
IsCodeGenOnly=1 to hide it from the assembly parser.
This does complicate the scheduler models a little since we can't assign the
A and BE instructions to a separate class now.
I plan to make similar changes for SETcc and Jcc.
Reviewers: RKSimon, spatel, lebedev.ri, andreadb, courbet
Reviewed By: RKSimon
Subscribers: gchatelet, hiraditya, kristina, lebedev.ri, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60041
llvm-svn: 357800
These inserters inserted some instructions to zero some registers and copied from virtual registers to physical registers.
This change instead inserts the zeros directly into the DAG at lowering time using new ISD opcodes
that take the extra zeroes as inputs. The zeros will then go through isel on their own to select
the MOV32r0 pseudo. Then we just need to mention the physical registers directly
in the isel patterns and the isel table and InstrEmitter will take care of inserting the necessary
copies to/from physical registers.
llvm-svn: 357659
This custom inserter existed so we could do a weird thing where we pretended that the instructions support
a full address mode instead of taking a pointer in EAX/RAX. I think was largely so we could be pointer
size agnostic in the isel pattern.
To make this work we would then put the address into an LEA into EAX/RAX in front of the instruction after
isel. But the LEA is overkill when we just have a base pointer. So we end up using the LEA as a slower MOV
instruction.
With this change we now just do custom selection during isel instead and just assign the incoming address
of the intrinsic into EAX/RAX based on its size. After the intrinsic is selected, we can let isel take
care of selecting an LEA or other operation to do any address computation needed in this basic block.
I've also split the instruction into a 32-bit mode version and a 64-bit mode version so the implicit
use is properly sized based on the pointer. Without this we get comments in the assembly output about
killing eax and defing rax or vice versa depending on whether we define the instruction to use EAX/RAX.
llvm-svn: 357652
This should allow llvm-exegesis to intelligently constrain the rounding mode.
The mask in the encoder shouldn't be necessary any more. We used to allow codegen to use 8-11 for rounding mode and the assembler would use 0-3 to mean the same thing so we masked here and in the printer. Codegen now matches the assembler and the printer was updated, but I forgot to update the encoder.
llvm-svn: 357419
Under optsize we try to avoid folding immediates into instructions under optsize. But if the immediate is 16-bits or 32 bits, but can be encoded as an 8-bit immediate we don't save enough from disabling the folding unless the immediate has enough uses to make up for the size of the move which is either 3 bytes or 5 bytes since there are no sign extended 8-bit moves. We would also save something if the immediate was a live out of the basic block and thus a move was unavoidable, but that would require a more advanced heuristic than just counting uses.
Note we only avoid folding multiple use immediates into the patterns that use X86ISD::ADD/SUB/XOR/OR/AND/CMP/ADC/SBB nodes and not the more common ISD::ADD/SUB/XOR/OR/AND nodes.
Differential Revision: https://reviews.llvm.org/D59522
llvm-svn: 356688
CMPXCHG8B was introduced on i586/pentium generation.
If its not enabled, limit the atomic width to 32 bits so the AtomicExpandPass will expand to lib calls. Unclear if we should be using a different limit for other configs. The default is 1024 and experimentation shows that using an i256 atomic will cause a crash in SelectionDAG.
Differential Revision: https://reviews.llvm.org/D59576
llvm-svn: 356631
This patch removes the following dag node opcodes from namespace X86ISD:
RDTSC_DAG,
RDTSCP_DAG,
RDPMC_DAG
The logic that expands RDTSC/RDPMC/XGETBV intrinsics is basically the same. The
only differences are:
RDTSC/RDTSCP don't implicitly read ECX.
RDTSCP also implicitly writes ECX.
I moved the common expansion logic into a helper function with the goal to get
rid of code repetition. That helper is now used for the expansion of
RDTSC/RDTSCP/RDPMC/XGETBV intrinsics.
No functional change intended.
Differential Revision: https://reviews.llvm.org/D59547
llvm-svn: 356546
The only thing the print methods currently need to know is the string to print for the memory size in intel syntax.
This patch merges the functions based on this string. If we ever need something else in the future, its easy to split them back out.
This reduces the number of cases in the assembly printers. It shrinks the intel printer to only use 7 bytes per instruction instead of 8.
llvm-svn: 356352
Previously we had a regular form of the instruction used when the immediate was 0-7. And _alt form that allowed the full 8 bit immediate. Codegen would always use the 0-7 form since the immediate was always checked to be in range. Assembly parsing would use the 0-7 form when a mnemonic like vpcomtrueb was used. If the immediate was specified directly the _alt form was used. The disassembler would prefer to use the 0-7 form instruction when the immediate was in range and the _alt form otherwise. This way disassembly would print the most readable form when possible.
The assembly parsing for things like vpcomtrueb relied on splitting the mnemonic into 3 pieces. A "vpcom" prefix, an immediate representing the "true", and a suffix of "b". The tablegenerated printing code would similarly print a "vpcom" prefix, decode the immediate into a string, and then print "b".
The _alt form on the other hand parsed and printed like any other instruction with no specialness.
With this patch we drop to one form and solve the disassembly printing issue by doing custom printing when the immediate is 0-7. The parsing code has been tweaked to turn "vpcomtrueb" into "vpcomb" and then the immediate for the "true" is inserted either before or after the other operands depending on at&t or intel syntax.
I'd rather not do the custom printing, but I tried using an InstAlias for each possible mnemonic for all 8 immediates for all 16 combinations of element size, signedness, and memory/register. The code emitted into printAliasInstr ended up checking the number of operands, the register class of each operand, and the immediate for all 256 aliases. This was repeated for both the at&t and intel printer. Despite a lot of common checks between all of the aliases, when compiled with clang at least this commonality was not well optimized. Nor do all the checks seem necessary. Since I want to do a similar thing for vcmpps/pd/ss/sd which have 32 immediate values and 3 encoding flavors, 3 register sizes, etc. This didn't seem to scale well for clang binary size. So custom printing seemed a better trade off.
I also considered just using the InstAlias for the matching and not the printing. But that seemed like it would add a lot of extra rows to the matcher table. Especially given that the 32 immediates for vpcmpps have 46 strings associated with them.
Differential Revision: https://reviews.llvm.org/D59398
llvm-svn: 356343
The feature flag alone can't be trusted since it can be passed via -mattr. Need to ensure 64-bit mode as well.
We had a 64 bit mode check on the instruction to make the assembler work correctly. But we weren't guarding any of our lowering code or the hooks for the AtomicExpandPass.
I've added 32-bit command lines to atomic128.ll with and without cx16. The tests there would all previously fail if -mattr=cx16 was passed to them. I had to move one test case for f128 to a new file as it seems to have a different 32-bit mode or possibly sse issue.
Differential Revision: https://reviews.llvm.org/D59308
llvm-svn: 356078
All of these instructions consume one encoded register and the other register is %st. They either write the result to %st or the encoded register. Previously we printed both arguments when the encoded register was written. And we printed one argument when the result was written to %st. For the stack popping forms the encoded register is always the destination and we didn't print both operands. This was inconsistent with gcc and objdump and just makes the output assembly code harder to read.
This patch changes things to always print both operands making us consistent with gcc and objdump. The parser should still be able to handle the single register forms just as it did before. This also matches the GNU assembler behavior.
llvm-svn: 353061
Looking into gcc and objdump behavior more this was overly aggressive. If the register is encoded in the instruction we should print %st(0), if its implicit we should print %st.
I'll be making a more directed change in a future patch.
llvm-svn: 353013
Summary:
When calculating clobbers for MS style inline assembly we fail if the asm clobbers stack top because we print st(0) and try to pass it through the gcc register name check. This was found with when I attempted to make a emms/femms clobber all ST registers. If you use emms/femms in MS inline asm we would try to use st(0) as the clobber name but clang would think that wasn't a valid clobber name.
This also matches what objdump disassembly prints. It's also what is printed by gcc -S.
Reviewers: RKSimon, rnk, efriedma, spatel, andreadb, lebedev.ri
Reviewed By: rnk
Subscribers: eraman, gbedwell, lebedev.ri, llvm-commits
Differential Revision: https://reviews.llvm.org/D57621
llvm-svn: 352985
As far as I can tell we already won't emit these aliases due to an operand count check in the tablegen code. Removing these because I couldn't make sense of the inconsistency between fadd and fmul from reading the code.
I checked the AsmMatcher and AsmWriter files before and after this change and there were no differences.
llvm-svn: 352608
The add+and sequence followed by a branch can
happen e.g. when looping over the set bits of an integer:
```
while (x != 0) {
func(x & ~x);
x &= x - 1;
}
```
Reviewed By: ctopper
Differential Revision: https://reviews.llvm.org/D57296
llvm-svn: 352306
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
INC/DEC are pretty much the same as ADD/SUB except that they don't update the C flag.
This patch removes the special nodes and just pattern matches from ADD/SUB during isel if the C flag isn't being used.
I had to avoid selecting DEC is the result isn't used. This will become a SUB immediate which will turned into a CMP later by optimizeCompareInstr. This lead to the one test change where we use a CMP instead of a DEC for an overflow intrinsic since we only checked the flag.
This also exposed a hole in our RMW flag matching use of hasNoCarryFlagUses. Our root node for the match is a store and there's no guarantee that all the flag users have been selected yet. So hasNoCarryFlagUses needs to check copyToReg and machine opcodes, but it also needs to check for the pre-match SETCC, SETCC_CARRY, BRCOND, and CMOV opcodes.
Differential Revision: https://reviews.llvm.org/D55975
llvm-svn: 350245
This fixes the patterns that have or/and as a root. 'and' is handled differently since thy usually have a CMP wrapped around them.
I had to look for uses of the CF flag because all these nodes have non-standard CF flag behavior. A real or/xor would always clear CF. In practice we shouldn't be using the CF flag from these nodes as far as I know.
Differential Revision: https://reviews.llvm.org/D55813
llvm-svn: 349962
The machine scheduler currently biases register copies to/from
physical registers to be closer to their point of use / def to
minimize their live ranges. This change extends this to also physical
register assignments from immediate values.
This causes a reduction in reduction in overall register pressure and
minor reduction in spills and indirectly fixes an out-of-registers
assertion (PR39391).
Most test changes are from minor instruction reorderings and register
name selection changes and direct consequences of that.
Reviewers: MatzeB, qcolombet, myatsina, pcc
Subscribers: nemanjai, jvesely, nhaehnle, eraman, hiraditya,
javed.absar, arphaman, jfb, jsji, llvm-commits
Differential Revision: https://reviews.llvm.org/D54218
llvm-svn: 346894
Summary:
The final pattern.
There is no test changes:
* We are looking for the pattern with one-use of it's mask,
* If the mask is one-use, D48768 will unfold it into pattern d.
* Thus, the tests have extra-use on the mask.
* Thus, only the BMI2 BZHI can be tested, and it already worked.
* So there is no BMI1 test coverage, we just assume it works since it uses the same codepath.
Reviewers: craig.topper, RKSimon
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53575
llvm-svn: 345584
This initially landed in rL345014, but was reverted in rL345017
due to sanitizer-x86_64-linux-fast buildbot failure in
check-lld (ELF/relocatable-versioned.s) test.
While i'm not yet quite sure what is the problem, one obvious
thing here is that extra truncation roundtrip.
Maybe that's it? If not, will re-revert.
Differential Revision: https://reviews.llvm.org/D53521
llvm-svn: 345027
Summary:
Continuation of D52348.
We also get the `c) x & (-1 >> (32 - y))` pattern here, because of the D48768.
I will add extra-uses into those tests and follow-up with a patch to handle those patterns too.
Reviewers: RKSimon, craig.topper
Reviewed By: craig.topper
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53521
llvm-svn: 345014
A while ago we changed pushf and popf in Intel mode to generate pushfq
and popfq. Unfortunately that left us with no way to get the 16-bit
encoding in Intel mode so this patch adds pushfw and popfw as aliases
there.
llvm-svn: 344949
Summary:
As discussed in D52304 / IRC, we now have pattern matching for
'bit extract' in two places - tablegen and `X86DAGToDAGISel`.
There are 4 patterns.
And we will have a problem with `x & (-1 >> (32 - y))` pattern.
* If the mask is one-use, then it is always unfolded into `x << (32 - y) >> (32 - y)` first.
Thus, the existing test coverage is already broken.
* If it is not one-use, then it is not unfolded, and is matched as BZHI.
* If it is not one-use, we will not match it as BEXTR. And if it is one-use, it will have been unfolded already.
So we will either not handle that pattern for BEXTR, or not have test coverage for it.
This is bad.
As discussed with @craig.topper, let's unify this matching, and do everything in `X86DAGToDAGISel`.
Then we will not have code duplication, and will have proper test coverage.
This indeed does not affect any tests, and this is great.
It means that for these two patterns, the `X86DAGToDAGISel` is identical to the tablegen version.
Please review carefully, i'm not fully sure about that intrinsic change, and introduction of the new `X86ISD` opcode.
Reviewers: craig.topper, RKSimon, spatel
Reviewed By: craig.topper
Subscribers: llvm-commits, craig.topper
Differential Revision: https://reviews.llvm.org/D53164
llvm-svn: 344904
Currently we hardcode instructions with ReadAfterLd if the register operands don't need to be available until the folded load has completed. This doesn't take into account the different load latencies of different memory operands (PR36957).
This patch adds a ReadAfterFold def into X86FoldableSchedWrite to replace ReadAfterLd, allowing us to specify the load latency at a scheduler class level.
I've added ReadAfterVec*Ld classes that match the XMM/Scl, XMM and YMM/ZMM WriteVecLoad classes that we currently use, we can tweak these values in future patches once this infrastructure is in place.
Differential Revision: https://reviews.llvm.org/D52886
llvm-svn: 343868
This patch adds a 'WriteCopy' [WriteLoad, WriteStore] schedule sequence instead to better model the behaviour
Found by @andreadb during llvm-mca testing on btver2 which was crashing on "zero uop" WriteRMW only instructions
llvm-svn: 343708
subtarget features for indirect calls and indirect branches.
This is in preparation for enabling *only* the call retpolines when
using speculative load hardening.
I've continued to use subtarget features for now as they continue to
seem the best fit given the lack of other retpoline like constructs so
far.
The LLVM side is pretty simple. I'd like to eventually get rid of the
old feature, but not sure what backwards compatibility issues that will
cause.
This does remove the "implies" from requesting an external thunk. This
always seemed somewhat questionable and is now clearly not desirable --
you specify a thunk the same way no matter which set of things are
getting retpolines.
I really want to keep this nicely isolated from end users and just an
LLVM implementation detail, so I've moved the `-mretpoline` flag in
Clang to no longer rely on a specific subtarget feature by that name and
instead to be directly handled. In some ways this is simpler, but in
order to preserve existing behavior I've had to add some fallback code
so that users who relied on merely passing -mretpoline-external-thunk
continue to get the same behavior. We should eventually remove this
I suspect (we have never tested that it works!) but I've not done that
in this patch.
Differential Revision: https://reviews.llvm.org/D51150
llvm-svn: 340515
Luo, Yuanke