Summary:
This is one possible solution to the problem of ignoring constraints that Simon
raised in D21473 but it's a bit of a hack.
The integrated assembler currently ignores violations of the tied register
constraints when the operands involved in a tie are both present in the AsmText.
For example, 'dati $rs, $rt, $imm' with the '$rs = $rt' will silently replace
$rt with $rs. So 'dati $2, $3, 1' is processed as if the user provided
'dati $2, $2, 1' without any diagnostic being emitted.
This is difficult to solve properly because there are multiple parts of the
matcher that are silently forcing these constraints to be met. Tied operands are
rendered to instructions by cloning previously rendered operands but this is
unnecessary because the matcher was already instructed to render the operand it
would have cloned. This is also unnecessary because earlier code has already
replaced the MCParsedOperand with the one it was tied to (so the parsed input
is matched as if it were 'dati <RegIdx 2>, <RegIdx 2>, <Imm 1>'). As a result,
it looks like fixing this properly amounts to a rewrite of the tied operand
handling which affects all targets.
This patch however, merely inserts a checking hook just before the
substitution of MCParsedOperands and the Mips target overrides it. It's not
possible to accurately check the registers are the same this early (because
numeric registers haven't been bound to a register class yet) so it cheats a
bit and checks that the tokens that produced the operand are lexically
identical. This works because tied registers need to have the same register
class but it does have a flaw. It will reject 'dati $4, $a0, 1' for violating
the constraint even though $a0 ends up as the same register as $4.
Reviewers: sdardis
Subscribers: dsanders, llvm-commits, sdardis
Differential Revision: https://reviews.llvm.org/D21994
llvm-svn: 276867
They were all auto-incremented from 0 anyway, and I'm getting really annoying
conflicts and runtime failures when different people add more for GlobalISel
(and even when I'm refactoring my own patches).
NFC.
llvm-svn: 276204
This is for a situation where the encoding for a register may be
different depending on the specific operand. For some instructions,
we want to apply additional restrictions beyond the encoding's
constraints.
In AMDGPU some operands are VSrc_32, using the VS_32 pseudo register
class which accept VGPRs, SGPRs, or immediates in the encoding.
Some specific instructions with the same encoding operand do not want
to allow immediates or SGPRs, but the encoding format is different
in this case than a regular VGPR_32 operand.
This allows specifying the encoding should be treated the same
without introducing yet another dummy register class.
llvm-svn: 275929
This splits out the intrinsic table such that generic intrinsics come
first and target specific intrinsics are grouped by target. From here
we can find out which target an intrinsic is for or differentiate
between generic and target intrinsics.
The motivation here is to make it easier to move target specific
intrinsic handling out of generic code.
llvm-svn: 275575
Summary:
In this patch we implement the following parts of XRay:
- Supporting a function attribute named 'function-instrument' which currently only supports 'xray-always'. We should be able to use this attribute for other instrumentation approaches.
- Supporting a function attribute named 'xray-instruction-threshold' used to determine whether a function is instrumented with a minimum number of instructions (IR instruction counts).
- X86-specific nop sleds as described in the white paper.
- A machine function pass that adds the different instrumentation marker instructions at a very late stage.
- A way of identifying which return opcode is considered "normal" for each architecture.
There are some caveats here:
1) We don't handle PATCHABLE_RET in platforms other than x86_64 yet -- this means if IR used PATCHABLE_RET directly instead of a normal ret, instruction lowering for that platform might do the wrong thing. We think this should be handled at instruction selection time to by default be unpacked for platforms where XRay is not availble yet.
2) The generated section for X86 is different from what is described from the white paper for the sole reason that LLVM allows us to do this neatly. We're taking the opportunity to deviate from the white paper from this perspective to allow us to get richer information from the runtime library.
Reviewers: sanjoy, eugenis, kcc, pcc, echristo, rnk
Subscribers: niravd, majnemer, atrick, rnk, emaste, bmakam, mcrosier, mehdi_amini, llvm-commits
Differential Revision: http://reviews.llvm.org/D19904
llvm-svn: 275367
Ran clang-format to remove the namespace indentation, and stopped
repeating names in doc comments since I was updating every line
anyway.
llvm-svn: 274919
The way the named arguments for various system instructions are handled at the
moment has a few problems:
- Large-scale duplication between AArch64BaseInfo.h and AArch64BaseInfo.cpp
- That weird Mapping class that I have no idea what I was on when I thought
it was a good idea.
- Searches are performed linearly through the entire list.
- We print absolutely all registers in upper-case, even though some are
canonically mixed case (SPSel for example).
- The ARM ARM specifies sysregs in terms of 5 fields, but those are relegated
to comments in our implementation, with a slightly opaque hex value
indicating the canonical encoding LLVM will use.
This adds a new TableGen backend to produce efficiently searchable tables, and
switches AArch64 over to using that infrastructure.
llvm-svn: 274576
Summary:
This complements the earlier addition of IntrWriteMem and IntrWriteArgMem
LLVM intrinsic properties, see D18291.
Also start using the attribute for memset, memcpy, and memmove intrinsics,
and remove their special-casing in BasicAliasAnalysis.
Reviewers: reames, joker.eph
Subscribers: joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D18714
llvm-svn: 274485
The previous code would always do 1 or 2 prefix compares;
explicitly only do one.
This speeds up debug -gen-asm-matcher by ~10% (e.g. X86: 40s -> 35s).
llvm-svn: 273583
Currently isComplete = 1 requires that every instruction must
be described, declared unsupported or marked as having no
scheduling information for a processor.
For some backends such as MIPS, this requirement entails
long regex lists of instructions that are unsupported.
This patch teaches Tablegen to skip over instructions that
are associated with unsupported feature when checking if the
scheduling model is complete.
Patch by: Daniel Sanders
Contributions by: Simon Dardis
Reviewers: MatzeB
Differential Reviewer: http://reviews.llvm.org/D20522
llvm-svn: 273551
looking for it along $PATH. This allows installs of LLVM tools outside of
$PATH to find the symbolizer and produce pretty backtraces if they crash.
llvm-svn: 272232
will appear after a blank. This assumption does not hold in the ARM
target.
Patch by: Roger Ferrer Ibanez
Differential Revision: http://reviews.llvm.org/D20234
llvm-svn: 271666
consider the Predicates attached to InstAlias when generating printAliasInstr.
This forces users of printAliasInstr to check those predicates beforehand.
This commit adds them in the condition set of the IAPrinter object.
Patch by: Roger Ferrer Ibanez
Differential Revision: http://reviews.llvm.org/D20233
llvm-svn: 271665
This means SelectCode unconditionally returns nullptr now. I'll follow
up with a change to make that return void as well, but it seems best
to keep that one very mechanical.
This is part of the work to have Select return void instead of an
SDNode *, which is in turn part of llvm.org/pr26808.
llvm-svn: 269136
Summary:
This change allows to specify "DefaultMethod" for optional operand (IsOptional = 1) in AsmOperandClass that return default value for operand. This is used in convertToMCInst to set default values in MCInst.
Previously if you wanted to set default value for operand you had to create custom converter method. With this change it is possible to use standard converters even when optional operands presented.
Reviewers: tstellarAMD, ab, craig.topper
Subscribers: jyknight, dsanders, arsenm, nhaustov, llvm-commits
Differential Revision: http://reviews.llvm.org/D18242
llvm-svn: 268726
Pattern predicates already appear to be emitted as far down as they can be. The optimization was making no changes on any in-tree target.
llvm-svn: 268705
This opcode never happens in practice, and yet the logic we have in
place to handle it would be undefined behaviour if we ever executed
it. Remove it rather than trying to refactor code that's never
reached.
llvm-svn: 268692
This function performs the reverse computation of
composeSubRegIndexLaneMask().
It will be used in the upcoming "DetectDeadLanes" pass.
llvm-svn: 267849
Previously using lanemasks on registers without any subregisters was not
well defined. This commit extends TargetRegisterInfo/tablegen to:
- Report a lanemask of 1 for regclasses without subregisters
- Do the right thing when mapping a 0/1 lanemask from a class without
subregisters into a class with subregisters in
TargetRegisterInfo::composeSubRegIndexLaneMasks().
This will be used in the upcoming "DetectDeadLanes" patch.
llvm-svn: 267848
Summary:
IntrReadWriteArgMem simply becomes IntrArgMemOnly.
So there are fewer intrinsic properties that express their orthogonality
better, and correspond more closely to the corresponding IR attributes.
Suggested by: Philip Reames
Reviewers: joker.eph, reames, tstellarAMD
Subscribers: jholewinski, arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D19291
llvm-svn: 267021
Justin Bogner