For the MIPS O32 ABI, the current call lowering logic naively lowers each
call, creating the reserved argument area to hold the argument spill areas for
$a0..$a3 and the outgoing parameter area if one is required at each call site.
In the case of a sufficently large byval argument, a call to memcpy is used
to write the start+16..end of the argument into the outgoing parameter area.
This is done within the CALLSEQ_START..CALLSEQ_END of the callee. The CALLSEQ
nodes are responsible for performing the necessary stack adjustments.
Since the O32/N32/N64 MIPS ABIs do not have a red-zone and writing below the
stack pointer and reading the values back is unpredictable, the call to memcpy
cannot be hoisted out of the callee's CALLSEQ nodes.
However, for the O32 ABI requires the reserved argument area for functions
which have parameters. The naive lowering of calls will then create nested
CALLSEQ sequences. For N32 and N64 these nodes are also created, but with
zero stack adjustments as those ABIs do not have a reserved argument area.
This patch addresses the correctness issue by recognizing the special case
of lowering a byval argument that uses memcpy. By recognizing that the
incoming chain already has a CALLSEQ_START node on it when calling memcpy,
the CALLSEQ nodes are not created. For the N32 and N64 ABIs, this is not an
issue, as no stack adjustment has to be performed.
For the O32 ABI, the correctness reasoning is different. In the case of a
sufficently large byval argument, registers a0..a3 are going to be used for
the callee's arguments, mandating the creation of the reserved argument area.
The call to memcpy in the naive case will also create its own reserved
argument area. However, since the reserved argument area consists of undefined
values, both calls can use the same reserved argument area.
Reviewers: abeserminji, atanasyan
Differential Revision: https://reviews.llvm.org/D44296
llvm-svn: 327388
Emulated TLS is enabled by llc flag -emulated-tls,
which is passed by clang driver.
When llc is called explicitly or from other drivers like LTO,
missing -emulated-tls flag would generate wrong TLS code for targets
that supports only this mode.
Now use useEmulatedTLS() instead of Options.EmulatedTLS to decide whether
emulated TLS code should be generated.
Unit tests are modified to run with and without the -emulated-tls flag.
Differential Revision: https://reviews.llvm.org/D42999
llvm-svn: 326341
Re-enable commit r323991 now that r325931 has been committed to make
MachineOperand::isRenamable() check more conservative w.r.t. code
changes and opt-in on a per-target basis.
llvm-svn: 326208
Add GlobalISel infrastructure up to the point where we can select a ret
void.
Patch by Petar Avramovic.
Differential Revision: https://reviews.llvm.org/D43583
llvm-svn: 325888
Enable multiple COPY hints to eliminate more COPYs during register allocation.
Note that this is something all targets should do, see
https://reviews.llvm.org/D38128.
Review: Simon Dardis
llvm-svn: 325870
There were no memory dependencies made between stores generated
when lowering formal arguments and loads generated when
call lowering byVal arguments which made the Post-RA scheduler
place a load before a matching store.
Make the fixed object stored to mutable so that the load
instructions can have their memory dependencies added
Set the frame object as isAliased which clears the underlying
objects vector in ScheduleDAGInstrs::buildSchedGraph().
This results in addition of all stores as dependenies for loads.
This problem appeared when passing a byVal parameter
coupled with a fastcc function call.
Differential Revision: https://reviews.llvm.org/D37515
llvm-svn: 325782
This patch provides mitigation for CVE-2017-5715, Spectre variant two,
which affects the P5600 and P6600. It implements the LLVM part of
-mindirect-jump=hazard. It is _not_ enabled by default for the P5600.
The migitation strategy suggested by MIPS for these processors is to use
hazard barrier instructions. 'jalr.hb' and 'jr.hb' are hazard
barrier variants of the 'jalr' and 'jr' instructions respectively.
These instructions impede the execution of instruction stream until
architecturally defined hazards (changes to the instruction stream,
privileged registers which may affect execution) are cleared. These
instructions in MIPS' designs are not speculated past.
These instructions are used with the attribute +use-indirect-jump-hazard
when branching indirectly and for indirect function calls.
These instructions are defined by the MIPS32R2 ISA, so this mitigation
method is not compatible with processors which implement an earlier
revision of the MIPS ISA.
Performance benchmarking of this option with -fpic and lld using
-z hazardplt shows a difference of overall 10%~ time increase
for the LLVM testsuite. Certain benchmarks such as methcall show a
substantially larger increase in time due to their nature.
Reviewers: atanasyan, zoran.jovanovic
Differential Revision: https://reviews.llvm.org/D43486
llvm-svn: 325653
This reverts commit r323991.
This commit breaks target that don't model all the register constraints
in TableGen. So far the workaround was to set the
hasExtraXXXRegAllocReq, but it proves that it doesn't cover all the
cases.
For instance, when mutating an instruction (like in the lowering of
COPYs) the isRenamable flag is not properly updated. The same problem
will happen when attaching machine operand from one instruction to
another.
Geoff Berry is working on a fix in https://reviews.llvm.org/D43042.
llvm-svn: 325421
These instructions conflict with their full length variants
for the purposes of FastISel as they cannot be distingushed
based on the number and type of operands and predicates.
Reviewers: atanasyan
Differential Revision: https://reviews.llvm.org/D41285
llvm-svn: 325341
This is mainly a move of simplifyShuffleOperands from DAGCombiner::visitVECTOR_SHUFFLE to create a more general purpose TargetLowering::SimplifyDemandedVectorElts implementation.
Further features can be moved/added in future patches.
Differential Revision: https://reviews.llvm.org/D42896
llvm-svn: 325232
In case of correct using of the 'l' constraint llvm now generates valid
code; otherwise it shows an error message. Initially these triggers an
assertion.
This commit is the same as r324869 with fixed the test's file name.
llvm-svn: 324885
In case of correct using of the 'l' constraint llvm now generates valid
code; otherwise it shows an error message. Initially these triggers an
assertion.
llvm-svn: 324869
r314974 introduced insertion of DEBUG_VALUEs after
each redefinition of debug value register in the slot index range.
In case the instruction redefining the debug value register
was a terminator, machine verifier would complain since it
enforces the rule of no non-terminator instructions
following the first terminator.
Differential Revision: https://reviews.llvm.org/D42801
llvm-svn: 324734
When adding operands to machine instructions in case of
RegisterSDNodes, generate a COPY node in case the register class
does not match the one in the instruction definition.
Differental Revision: https://reviews.llvm.org/D35561
llvm-svn: 324733
Instructions affected:
mthc1, mfhc1, add.d, sub.d, mul.d, div.d,
mov.d, neg.d, cvt.w.d, cvt.d.s, cvt.d.w, cvt.s.d
These instructions are now defined for
microMIPS32r3 + microMIPS32r6 in MicroMipsInstrFPU.td
since they shared their encoding with those already defined
in microMIPS32r6InstrInfo.td and have been therefore
removed from the latter file.
Some instructions present in MicroMipsInstrFPU.td which
did not have both AFGR64 and FGR64 variants defined have
been altered to do so.
Differential revision: https://reviews.llvm.org/D42738
llvm-svn: 324584
Both operand codes now work the same way in case of register or memory
operands. It print high-order or low-order word in a double-word
register or memory location.
llvm-svn: 324476
For example 'ugt X, 0' can be simplified to 'ne X, 0'. Or 'uge X, 0' is always true.
We already simplify this for scalars in SimplifySetCC, but we don't currently for vectors in SimplifySetCC. D42948 proposes to change that.
llvm-svn: 324436
Summary:
This change extends MachineCopyPropagation to do COPY source forwarding
and adds an additional run of the pass to the default pass pipeline just
after register allocation.
This version of this patch uses the newly added
MachineOperand::isRenamable bit to avoid forwarding registers is such a
way as to violate constraints that aren't captured in the
Machine IR (e.g. ABI or ISA constraints).
This change is a continuation of the work started in D30751.
Reviewers: qcolombet, javed.absar, MatzeB, jonpa, tstellar
Subscribers: tpr, mgorny, mcrosier, nhaehnle, nemanjai, jyknight, hfinkel, arsenm, inouehrs, eraman, sdardis, guyblank, fedor.sergeev, aheejin, dschuff, jfb, myatsina, llvm-commits
Differential Revision: https://reviews.llvm.org/D41835
llvm-svn: 323991
This patch includes EVA instructions in the Std2MicroMips mapping
tables, which is required for direct object emission.
Differential Revision: https://reviews.llvm.org/D41771
llvm-svn: 323958
Discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120320.html
In preparation for adding support for named vregs we are changing the sigil for
physical registers in MIR to '$' from '%'. This will prevent name clashes of
named physical register with named vregs.
llvm-svn: 323922
PR36061 showed that during the expansion of ISD::FPOWI, that there
was an incorrect zero extension of the integer argument which for
MIPS64 would then give incorrect results. Address this with the
existing mechanism for correcting sign extensions.
This resolves PR36061.
Thanks to James Cowgill for reporting the issue!
Reviewers: atanasyan, hfinkel
Differential Revision: https://reviews.llvm.org/D42537
llvm-svn: 323781
Summary:
Fix a few places that were modifying code after register
allocation to set the renamable bit correctly to avoid failing the
validation added in D42449.
llvm-svn: 323675
- Alter abs for micromips to have both AFGR64 and FGR64
variants, same as sqrt
- Remove sqrt and abs from MicroMips32r6InstrInfo.td,
use micromips FGR64 variants
- Restrict non-micromips abs/sqrt with NotInMicroMips
predicate
Differential revision: https://reviews.llvm.org/D41439
llvm-svn: 323184
Dsp and dspr2 require MIPS revision 2, while msa requires revision 5. Adding
warnings for cases when these flags are used with earlier revision.
Patch by Milos Stojanovic.
Differential Revision: https://reviews.llvm.org/D40490
llvm-svn: 323131
Planning to add support for named vregs. This puts is in a conundrum since
physregs are named as well. To rectify this we need to use a sigil other than
'%' for physregs in MIR. We've settled on using '$' for physregs but first we
must repurpose it from external symbols using it, which is what this commit is
all about. We think '&' will have familiar semantics for C/C++ users.
llvm-svn: 322146
Initially, if the `c` constraint applied to the wrong data type that
causes LLVM to assert. This commit replaces the assert by an error
message.
llvm-svn: 321565
This seems to improve X86's ability to match this into an address computation. Otherwise the other operand gets assigned to the base register and the stack pointer + frame index ends up in the index register. But index registers can't encode ESP/RSP so we end up having to move it into another register to meet the constraint.
I could try to improve the address matcher in X86, but swapping the producer seemed easier. Several other places already have the operands in this order so this is at least consistent.
llvm-svn: 321370
This instruction is encoded as zero, so we have handle that case when checking
for unimplemented opcodes when producing the encoding for an instruction.
llvm-svn: 321066
Fix an off by one error in the bounds checking for 'dinsu' and update
the ranges in the test comments so that they are accurate.
This version has the correct commit message.
Reviewers: atanasyan
Differential Revision: https://reviews.llvm.org/D41183
llvm-svn: 320991
Fix an off by one error in the bounds checking for 'dinsu' and update
the ranges in the test comments so that they are accurate.
Reviewers: atanasyan
https://reviews.llvm.org/D41183
llvm-svn: 320974
MIPSR6 introduced several new jump instructions and deprecated
the use of the 'j' instruction. For microMIPS32R6, 'j' was removed
entirely and it only has non delay slot jumps.
This patch adds support for MIPSR6 by using some R6 instructions--
'bc' instead of 'j', 'jic $reg, 0' instead of 'jalr $zero, $reg'--
and modifies the sequences not to use delay slots for R6.
Reviewers: atanasyan
Reviewed By: atanasyan
Subscribers: dschuff, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D40786
llvm-svn: 320703
Previously, v2i16 -> f32 bitcast could not be matched.
Add patterns to support matching this and similar types of bitcasts.
Differential revision: https://reviews.llvm.org/D40959
llvm-svn: 320562
All files and parts of files related to microMIPS4R6 are removed.
When target is microMIPS4R6, errors are printed.
This is LLVM part of patch.
Differential Revision: https://reviews.llvm.org/D35625
llvm-svn: 320350
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.
The MIR printer prints the IR name of a MBB only for block definitions.
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix
Differential Revision: https://reviews.llvm.org/D40422
llvm-svn: 319665
output
As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.
Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.
Differential Revision: https://reviews.llvm.org/D40421
llvm-svn: 319445
As part of the unification of the debug format and the MIR format,
always print registers as lowercase.
* Only debug printing is affected. It now follows MIR.
Differential Revision: https://reviews.llvm.org/D40417
llvm-svn: 319187
Unoptimized IR can have linear sequences of stores to an array, where the
initial GEP for the first store is formed from the pointer to the array, and the
GEP for each store after the first is formed from the previous GEP with some
offset in an inductive fashion.
The (large) resulting DAG when analyzed by DAGCombine undergoes an excessive
number of combines as each store node is examined every time its' offset node
is combined with any child of the offset. One of the transformations is
findBetterNeighborChains which assists MergeConsecutiveStores. The former
relies on repeated chain walking to do its' work, however MergeConsecutiveStores
is disabled at O0 which makes the transformation redundant.
Any optimization level other than O0 would invoke InstCombine which would
resolve the chain of GEPs into flat base + offset GEP for each store which
does not exhibit the repeated examination of each store to the array.
Disabling this optimization fixes an excessive compile time issue (30~ minutes
for the test case provided) at O0.
Reviewers: niravd, craig.topper, t.p.northover
Differential Revision: https://reviews.llvm.org/D40193
llvm-svn: 319142