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188655 Commits

Author SHA1 Message Date
Thomas Raoux
e196f6f63f [ModuloSchedule] Fix data types in ModuloScheduleExpander::isLoopCarried
The cycle values in modulo scheduling results can be negative.
The result of ModuloSchedule::getCycle() must be received as an int type.

Patch by Masaki Arai!

Differential Revision: https://reviews.llvm.org/D71122
2019-12-09 07:37:00 -08:00
James Henderson
54c73ec047 [test][llvm-cxxfilt] Add missing '-n'
See also e84468c1f.
2019-12-09 15:06:41 +00:00
James Henderson
3defb31026 [test][llvm-cxxfilt] Fix darwin build bot
When committing dba420bc05ae, I missed that a darwin-specific change had
been recently introduced into llvm-cxxfilt, which my change ignored and
consequently broke the darwin build bot. This change fixes this issue as
well as improving naming/commenting of things related to this point so
that people are less likely to run into the same issue as I did.
2019-12-09 14:01:14 +00:00
Sam Elliott
aabc412eff [RISCV] Fix mir-target-flags.ll 2019-12-09 13:51:08 +00:00
Sam Elliott
f9d1303c07 [RISCV] Machine Operand Flag Serialization
Summary:
These hooks ensure that the RISC-V backend can serialize and parse MIR
correctly.

Reviewers: jrtc27, luismarques

Reviewed By: luismarques

Subscribers: hiraditya, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, s.egerton, pzheng, sameer.abuasal, apazos, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70666
2019-12-09 13:18:32 +00:00
Djordje Todorovic
245ed172b5 [DebugInfo][EarlyCSE] Use the salvageDebugInfoOrMarkUndef(); NFC
Use the newest API.

Differential Revision: https://reviews.llvm.org/D71061
2019-12-09 13:57:35 +01:00
Jeremy Morse
e640a69d80 [DebugInfo] Nerf placeDbgValues, with prejudice
CodeGenPrepare::placeDebugValues moves variable location intrinsics to be
immediately after the Value they refer to. This makes tracking of locations
very easy; but it changes the order in which assignments appear to the
debugger, from the source programs order to the order in which the
optimised program computes values. This then leads to PR43986 and PR38754,
where variable locations that were in a conditional block are made
unconditional, which is highly misleading.

This patch adjusts placeDbgValues to only re-order variable location
intrinsics if they use a Value before it is defined, significantly reducing
the damage that it does. This is still not 100% safe, but the rest of
CodeGenPrepare needs polishing to correctly update debug info when
optimisations are performed to fully fix this.

This will probably break downstream debuginfo tests -- if the
instruction-stream position of variable location changes isn't the focus of
the test, an easy fix should be to manually apply placeDbgValues' behaviour
to the failing tests, moving dbg.value intrinsics next to SSA variable
definitions thus:

  %foo = inst1
  %bar = ...
  %baz = ...
  void call @llvm.dbg.value(metadata i32 %foo, ...

to

  %foo = inst1
  void call @llvm.dbg.value(metadata i32 %foo, ...
  %bar = ...
  %baz = ...

This should return your test to exercising whatever it was testing before.

Differential Revision: https://reviews.llvm.org/D58453
2019-12-09 12:52:10 +00:00
James Henderson
6fc6c6773a [test][tools] Add missing and improve testing
Mostly this adds testing for certain aliases in more explicit ways.
There are also a few tidy-ups, and additions of missing testing, where
the feature was either not tested at all, or not tested explicitly and
sufficiently.

Reviewed by: MaskRay, rupprecht, grimar

Differential Revision: https://reviews.llvm.org/D71116
2019-12-09 12:24:23 +00:00
Mikhail Maltsev
b45bad1e62 [ARM][MVE] Add complex vector intrinsics
Summary:
This patch adds intrinsics for the following MVE instructions:
* VCADD, VHCADD
* VCMUL
* VCMLA

Each of the above 3 groups has a corresponding new LLVM IR intrinsic.

Reviewers: simon_tatham, MarkMurrayARM, ostannard, dmgreen

Reviewed By: MarkMurrayARM

Subscribers: merge_guards_bot, kristof.beyls, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D71190
2019-12-09 12:05:59 +00:00
David Green
1d7bf55fa9 [ARM] Add missing REQUIRES: asserts to test. NFC 2019-12-09 11:43:43 +00:00
David Green
5ce4d154f5 [CommandLine] Add missing Callbacks
It appears that the cl::bits options are not used anywhere in-tree. In
the recent addition to add Callback's to the options, the Callback was
missing from this one. This fixes it by adding the same code from the
other classes.

It also adds a simple test, of sorts, just to make sure these continue
compiling.
2019-12-09 11:37:34 +00:00
David Green
ff57153d05 [ARM] Enable MVE masked loads and stores
With the extra optimisations we have done, these should now be fine to
enable by default. Which is what this patch does.

Differential Revision: https://reviews.llvm.org/D70968
2019-12-09 11:37:34 +00:00
LLVM GN Syncbot
0d4c7b371d gn build: Merge 6d5c273500a 2019-12-09 10:28:47 +00:00
David Green
5da8fa266d [ARM] Teach the Arm cost model that a Shift can be folded into other instructions
This attempts to teach the cost model in Arm that code such as:
  %s = shl i32 %a, 3
  %a = and i32 %s, %b
Can under Arm or Thumb2 become:
  and r0, r1, r2, lsl #3

So the cost of the shift can essentially be free. To do this without
trying to artificially adjust the cost of the "and" instruction, it
needs to get the users of the shl and check if they are a type of
instruction that the shift can be folded into. And so it needs to have
access to the actual instruction in getArithmeticInstrCost, which if
available is added as an extra parameter much like getCastInstrCost.

We otherwise limit it to shifts with a single user, which should
hopefully handle most of the cases. The list of instruction that the
shift can be folded into include ADC, ADD, AND, BIC, CMP, EOR, MVN, ORR,
ORN, RSB, SBC and SUB. This translates to Add, Sub, And, Or, Xor and
ICmp.

Differential Revision: https://reviews.llvm.org/D70966
2019-12-09 10:24:33 +00:00
David Green
bb8ae02f54 [ARM] Additional tests and minor formatting. NFC
This adds some extra cost model tests for shifts, and does some minor
adjustments to some Neon code to make it clear as to what it applies to.
Both NFC.
2019-12-09 10:24:33 +00:00
Pavel Labath
125e8487b9 [cmake] Disable GCC 9's -Wredundant-move
Summary:
This new warning (enabled by -Wextra) fires when a std::move is
redundant, as the default compiler behavior would be to select a move
operation anyway (e.g., when returning a local variable). Unlike
-Wpessimizing-move, it has no performance impact -- it just adds noise.

Currently llvm has about 1500 of these warnings. Unfortunately, the
suggested fix -- removing std::move -- does not work because of some
older compilers we still support. Specifically clang<=3.8 will not use a
move operation if an implicit conversion is needed (Core issue 1579). In
code like "A f(ConvertibleToA a) { return a; }" it will prefer a copy,
or fail to compile if a copy is not possible.

This patch disables that warning to get a meaningful signal out of a GCC
9 build.

Reviewers: rnk, aaron.ballman, xbolva00

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70963
2019-12-09 11:01:50 +01:00
David Stenberg
860d42802f [DebugInfo] Make describeLoadedValue() reg aware
Summary:
Currently the describeLoadedValue() hook is assumed to describe the
value of the instruction's first explicit define. The hook will not be
called for instructions with more than one explicit define.

This commit adds a register parameter to the describeLoadedValue() hook,
and invokes the hook for all registers in the worklist.

This will allow us to for example describe instructions which produce
more than two parameters' values; e.g. Hexagon's various combine
instructions.

This also fixes situations in our downstream target where we may pass
smaller parameters in the high part of a register. If such a parameter's
value is produced by a larger copy instruction, we can't describe the
call site value using the super-register, and we instead need to know
which sub-register that should be used.

This also allows us to handle cases like this:

  $ebx = [...]
  $rdi = MOVSX64rr32 $ebx
  $esi = MOV32rr $edi
  CALL64pcrel32 @call

The hook will first be invoked for the MOV32rr instruction, which will
say that @call's second parameter (passed in $esi) is described by $edi.
As $edi is not preserved it will be added to the worklist. When we get
to the MOVSX64rr32 instruction, we need to describe two values; the
sign-extended value of $ebx -> $rdi for the first parameter, and $ebx ->
$edi for the second parameter, which is now possible.

This commit modifies the dbgcall-site-lea-interpretation.mir test case.
In the test case, the values of some 32-bit parameters were produced
with LEA64r. Perhaps we can in general cases handle such by emitting
expressions that AND out the lower 32-bits, but I have not been able to
land in a case where a LEA64r is used for a 32-bit parameter instead of
LEA64_32 from C code.

I have not found a case where it would be useful to describe parameters
using implicit defines, so in this patch the hook is still only invoked
for explicit defines of forwarding registers.

Reviewers: djtodoro, NikolaPrica, aprantl, vsk

Reviewed By: djtodoro, vsk

Subscribers: ormris, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D70431
2019-12-09 10:47:49 +01:00
David Stenberg
d53d7803aa Revert "[DebugInfo] Make describeLoadedValue() reg aware"
This reverts commit 3cd93a4efcdeabeb20cb7bec9fbddcb540d337a1.
I'll recommit with a well-formatted arcanist commit message.
2019-12-09 10:45:13 +01:00
David Stenberg
c50f1b7c1a [DebugInfo] Make describeLoadedValue() reg aware
Currently the describeLoadedValue() hook is assumed to describe the
value of the instruction's first explicit define. The hook will not be
called for instructions with more than one explicit define.

This commit adds a register parameter to the describeLoadedValue() hook,
and invokes the hook for all registers in the worklist.

This will allow us to for example describe instructions which produce
more than two parameters' values; e.g. Hexagon's various combine
instructions.

This also fixes a case in our downstream target where we may pass
smaller parameters in the high part of a register. If such a parameter's
value is produced by a larger copy instruction, we can't describe the
call site value using the super-register, and we instead need to know
which sub-register that should be used.

This also allows us to handle cases like this:

  $ebx = [...]
  $rdi = MOVSX64rr32 $ebx
  $esi = MOV32rr $edi
  CALL64pcrel32 @call

The hook will first be invoked for the MOV32rr instruction, which will
say that @call's second parameter (passed in $esi) is described by $edi.
As $edi is not preserved it will be added to the worklist. When we get
to the MOVSX64rr32 instruction, we need to describe two values; the
sign-extended value of $ebx -> $rdi for the first parameter, and $ebx ->
$edi for the second parameter, which is now possible.

This commit modifies the dbgcall-site-lea-interpretation.mir test case.
In the test case, the values of some 32-bit parameters were produced
with LEA64r. Perhaps we can in general cases handle such by emitting
expressions that AND out the lower 32-bits, but I have not been able to
land in a case where a LEA64r is used for a 32-bit parameter instead of
LEA64_32 from C code.

I have not found a case where it would be useful to describe parameters
using implicit defines, so in this patch the hook is still only invoked
for explicit defines of forwarding registers.
2019-12-09 10:44:17 +01:00
Hans Wennborg
e5521eaffc Revert 393dacacf7e7 "[ARM] Enable TypePromotion by default"
This caused "Too many bits for uint64_t" asserts when building Chromium. See
https://crbug.com/1031978#c2 for a reproducer. I'll follow up on the
llvm-commits thread with a creduced version.

> ARMCodeGenPrepare has already been generalized and renamed to
> TypePromotion. We've had it enabled and tested downstream for a
> while, so enable it by default.
>
> Differential Revision: https://reviews.llvm.org/D70998
2019-12-09 09:39:31 +01:00
Amaury Séchet
ac47d50ba3 [PowerPC] Automatically generate store-constant.ll . NFC 2019-12-09 01:08:18 +01:00
Nico Weber
61fdc5dbdf Fix a few doc typos, to cycle bots. 2019-12-08 18:51:48 -05:00
rollrat
c70e2b4b91 [NFC][LivePhysRegs] Fix incorrect comment
Reviewers: #llvm, tellenbach

Reviewed By: tellenbach

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71051

Patch by: rollrat <rollrat.cse@gmail.com>
2019-12-08 21:07:28 +01:00
Sanjay Patel
03039d2315 [InstSimplify] fold copysign with negated operand, part 2
This is another transform suggested in PR44153:
https://bugs.llvm.org/show_bug.cgi?id=44153

Unlike rG12f39e0fede9, it doesn't look like the
backend matches this variant.
2019-12-08 10:16:29 -05:00
Sanjay Patel
0610119d84 [InstSimplify] fold copysign with negated operand
This is another transform suggested in PR44153:
https://bugs.llvm.org/show_bug.cgi?id=44153

The backend for some targets already manages to get
this if it converts copysign to bitwise logic.
2019-12-08 10:08:02 -05:00
Kristina Bessonova
e15019e197 [llvm-dwarfdump][Statistics] Unify coverage statistic computation
Summary:
The patch removes OffsetToFirstDefinition in the 'scope bytes total'
statistic computation. Thus it unifies the way the scope and the coverage
buckets are computed. The rationals behind that are the following:

1. OffsetToFirstDefinition was used to calculate the variable's life range.
However, there is no simple way to do it accurately, so the scope calculated
this way might be misleading. See D69027 for more details on the subject.
2. Both 'scope bytes total' and coverage buckets seem to be intended
to represent the same data in different ways. Otherwise, the statistics
might be controversial and confusing.

Note that the approach gives up a thorough evaluation of debug information
completeness (i.e. coverage buckets by themselves doesn't tell how good
the debug information is). Only changes in coverage over time make
a 'physical' sense.

Reviewers: djtodoro, aprantl, vsk, dblaikie, avl

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70548
2019-12-08 15:46:49 +03:00
David Green
6303dfd5cf [ARM] Attempt to use whole register vmovs for MVE shuffles.
MVE doesn't have the range of shuffle instructions available in Neon. We
also cannot use the trick of cutting a difficult vector shuffle in half
to simplify things. Instead we need to be more careful about how we
lower shuffles.

This patch adds an extra combine that attempts to find "whole lane"
vmovs when lowering shuffles of smaller types. This helps us make some
shuffles a lot simpler, generating single lane movs for the parts that
can make use of it, falling back to the original shuffle for the rest.

Differential Revision: https://reviews.llvm.org/D69509
2019-12-08 10:53:54 +00:00
David Green
db73d35912 [ARM] Disable VLD4 under MVE
Alas, using half the available vector registers in a single instruction
is just too much for the register allocator to handle. The mve-vldst4.ll
test here fails when these instructions are enabled at present. This
patch disables the generation of VLD4 and VST4 by adding a
mve-max-interleave-factor option, which we currently default to 2.

Differential Revision: https://reviews.llvm.org/D71109
2019-12-08 10:37:29 +00:00
Florian Hahn
08bd3ef50c [LV] Pick correct BB as insert point when fixing PHI for FORs.
Currently we fail to pick the right insertion point when
PreviousLastPart of a first-order-recurrence is a PHI node not in the
LoopVectorBody. This can happen when PreviousLastPart is produce in a
predicated block. In that case, we should pick the insertion point in
the BB the PHI is in.

Fixes PR44020.

Reviewers: hsaito, fhahn, Ayal, dorit

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D71071
2019-12-07 19:32:00 +00:00
Ulrich Weigand
8e47403d45 [SystemZ] Fix build bot failures
My patch 9db13b5a7d43096a9ab5f7cef6e1b7e2dc9c9c63 seems to have
caused some build bots to fail due to warnings that appear only
when using -Wcovered-switch-default.

This patch is an attempt to fix this by trying to avoid both the warning
"default label in switch which covers all enumeration values"
for the inner switch statements and at the same time the warning
"this statement may fall through"
for the outer switch statement in getVectorComparison
(SystemZISelLowering.cpp).
2019-12-07 19:37:16 +01:00
Florian Hahn
8ff0e9d433 [SimplifyCFG] Account for N being null.
Fixes a crash, e.g.
  http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/15119/
2019-12-07 17:23:42 +00:00
Yonghong Song
c66be60161 [BPF] Support weak global variables for BTF
Generate types for global variables with "weak" attribute.
Keep allocation scope the same for both weak and non-weak
globals as ELF symbol table can determine whether a global
symbol is weak or not.

Differential Revision: https://reviews.llvm.org/D71162
2019-12-07 08:58:19 -08:00
Rodrigo Caetano Rocha
22a6959eaa [SimplifyCFG] Handle AssumptionCache being null.
AssumptionCache can be null in SimplifyCFGOptions. However, FoldCondBranchOnPHI() was not properly handling that when passing a null AssumptionCache to simplifyCFG.

Patch by Rodrigo Caetano Rocha <rcor.cs@gmail.com>

Reviewers: fhahn, lebedev.ri, spatel

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D69963
2019-12-07 16:54:49 +00:00
Ulrich Weigand
b5b6e8e953 [FPEnv] Constrained FCmp intrinsics
This adds support for constrained floating-point comparison intrinsics.

Specifically, we add:

      declare <ty2>
      @llvm.experimental.constrained.fcmp(<type> <op1>, <type> <op2>,
                                          metadata <condition code>,
                                          metadata <exception behavior>)
      declare <ty2>
      @llvm.experimental.constrained.fcmps(<type> <op1>, <type> <op2>,
                                           metadata <condition code>,
                                           metadata <exception behavior>)

The first variant implements an IEEE "quiet" comparison (i.e. we only
get an invalid FP exception if either argument is a SNaN), while the
second variant implements an IEEE "signaling" comparison (i.e. we get
an invalid FP exception if either argument is any NaN).

The condition code is implemented as a metadata string.  The same set
of predicates as for the fcmp instruction is supported (except for the
"true" and "false" predicates).

These new intrinsics are mapped by SelectionDAG codegen onto two new
ISD opcodes, ISD::STRICT_FSETCC and ISD::STRICT_FSETCCS, again
representing quiet vs. signaling comparison operations.  Otherwise
those nodes look like SETCC nodes, with an additional chain argument
and result as usual for strict FP nodes.  The patch includes support
for the common legalization operations for those nodes.

The patch also includes full SystemZ back-end support for the new
ISD nodes, mapping them to all available SystemZ instruction to
fully implement strict semantics (scalar and vector).

Differential Revision: https://reviews.llvm.org/D69281
2019-12-07 11:28:39 +01:00
LLVM GN Syncbot
3f8cd19ea3 gn build: Merge e60b36cf92e 2019-12-07 08:57:51 +00:00
Florian Hahn
c0a866cb87 [VPlan] Rename VPlanHCFGTransforms to VPlanTransforms (NFC).
The file is intended to gather various VPlan transformations, not only
CFG related transforms. Actually, the only transformation there is not
CFG related.

Reviewers: Ayal, gilr, hsaito, rengolin

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D70732
2019-12-07 08:56:35 +00:00
Kai Luo
485e7e7049 [PowerPC] Fix MI peephole optimization for splats
Summary:
This patch fixes an issue where the PPC MI peephole optimization pass incorrectly remove a vector swap.

Specifically, the pass can combine a splat/swap to a splat/copy. It uses `TargetRegisterInfo::lookThruCopyLike` to determine that the operands to the splat are the same. However, the current logic only compares the operands based on register numbers. In the case where the splat operands are ultimately feed from the same physical register, the pass can incorrectly remove a swap if the feed register for one of the operands has been clobbered.

This patch adds a check to ensure that the registers feeding are both virtual registers or the operands to the splat or swap are both the same register.

Here is an example in pseudo-MIR of what happens in the test cased added in this patch:

Before PPC MI peephole optimization:
```
%arg = XVADDDP %0, %1

$f1 = COPY %arg.sub_64
call double rint(double)
%res.first = COPY $f1
%vec.res.first = SUBREG_TO_REG 1, %res.first, %subreg.sub_64

%arg.swapped = XXPERMDI %arg, %arg, 2
$f1 = COPY %arg.swapped.sub_64
call double rint(double)
%res.second = COPY $f1

%vec.res.second = SUBREG_TO_REG 1, %res.second, %subreg.sub_64
%vec.res.splat = XXPERMDI %vec.res.first, %vec.res.second, 0
%vec.res = XXPERMDI %vec.res.splat, %vec.res.splat, 2
; %vec.res == [ %vec.res.second[0], %vec.res.first[0] ]
```

After optimization:
```
; ...
%vec.res.splat = XXPERMDI %vec.res.first, %vec.res.second, 0
; lookThruCopyLike(%vec.res.first) == lookThruCopyLike(%vec.res.second) == $f1
; so the pass replaces the swap with a copy:
%vec.res = COPY %vec.res.splat
; %vec.res == [ %vec.res.first[0], %vec.res.second[0] ]
```

As best as I can tell, this has occurred since r288152, which added support for lowering certain vector operations to direct moves in the form of a splat.

Committed for vddvss (Colin Samples). Thanks Colin for the patch!
Differential Revision: https://reviews.llvm.org/D69497
2019-12-07 14:51:20 +08:00
Tom Stellard
8ecd409463 export.sh: Fetch sources from GitHub instead of SVN
Reviewers: hansw, jdoerfert

Subscribers: sylvestre.ledru, mgorny, hans, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70460
2019-12-06 18:57:08 -08:00
Amara Emerson
a902bd320c [AArch64][GlobalISel] Add missing default statement to a switch in the selector. 2019-12-06 17:43:27 -08:00
Sterling Augustine
07ff52ab90 Move variable only used in an assert into the assert itself.
This prevents unused variable warnings from breaking the build.
2019-12-06 17:09:19 -08:00
Amara Emerson
39754a683f [AArch64][GlobalISel] Add support for selection of vector G_SHL with immediates.
Only implemented for the type combinations already supported for G_SHL.

Differential Revision: https://reviews.llvm.org/D71153
2019-12-06 16:24:57 -08:00
Peter Collingbourne
563db3c456 gn build: Change scudo's list of supported platforms to a whitelist.
Scudo only supports building for android/linux/fuchsia, so require target_os to
be one of linux/fuchsia to do a stage2_unix scudo build. Android is already
covered by the stage2_android* toolchains below.

Differential Revision: https://reviews.llvm.org/D71131
2019-12-06 15:53:54 -08:00
Don Hinton
4da312a2f1 [CommandLine] Add callbacks to Options
Summary:
Add a new cl::callback attribute to Option.

This attribute specifies a callback function that is called when
an option is seen, and can be used to set other options, as in
option A implies option B.  If the option is a `cl::list`, and
`cl::CommaSeparated` is also specified, the callback will fire
once for each value.  This could be used to validate combinations
or selectively set other options.

Reviewers: beanz, thomasfinch, MaskRay, thopre, serge-sans-paille

Reviewed By: beanz

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70620
2019-12-06 15:16:45 -08:00
Sam Clegg
7d2c6fd3c7 [WebAssebmly][MC] Support .import_name/.import_field asm directives
Convert the MC test to use asm rather than bitcode.

This is a precursor to https://reviews.llvm.org/D70520.

Differential Revision: https://reviews.llvm.org/D70877
2019-12-06 15:09:56 -08:00
Reid Kleckner
e3b8614158 [MC] Rewrite tablegen for printInstrAlias to comiple faster, NFC
Before this change, the *InstPrinter.cpp files of each target where some
of the slowest objects to compile in all of LLVM. See this snippet produced by
ClangBuildAnalyzer:
https://reviews.llvm.org/P8171$96
Search for "InstPrinter", and see that it shows up in a few places.

Tablegen was emitting a large switch containing a sequence of operand checks,
each of which created many conditions and many BBs. Register allocation and
jump threading both did not scale well with such a large repetitive sequence of
basic blocks.

So, this change essentially turns those control flow structures into
data. The previous structure looked like:

  switch (Opc) {
  case TGT::ADD:
    // check alias 1
    if (MI->getOperandCount() == N && // check num opnds
        MI->getOperand(0).isReg() && // check opnd 0
        ...
        MI->getOperand(1).isImm() && // check opnd 1
     AsmString = "foo";
     break;
   }
   // check alias 2
   if (...)
     ...
   return false;

The new structure looks like:

  OpToPatterns: Sorted table of opcodes mapping to pattern indices.
   \->
     Patterns: List of patterns. Previous table points to subrange of
               patterns to match.
      \->
        Conds: The if conditions above encoded as a kind and 32-bit value.

See MCInstPrinter.cpp for the details of how the new data structures are
interpreted.

Here are some before and after metrics.
Time to compile AArch64InstPrinter.cpp:
  0m29.062s vs. 0m2.203s
size of the obj:
  3.9M vs. 676K
size of clang.exe:
  97M vs. 96M

I have not benchmarked disassembly performance, but typically
disassemblers are bottlenecked on IO and string processing, not alias
matching, so I'm not sure it's interesting enough to be worth doing.

Reviewers: RKSimon, andreadb, xbolva00, craig.topper

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D70650
2019-12-06 15:00:18 -08:00
Amara Emerson
c4c92d3e17 [X86] Fix prolog/epilog mismatch for stack protectors on win32-macho.
The xor'ing behaviour is only used for msvc/crt environments, when we're targeting
macho the guard load code doesn't know about the xor in the epilog. Disable xor'ing
when targeting win32-macho to be consistent.

Differential Revision: https://reviews.llvm.org/D71095
2019-12-06 14:44:56 -08:00
Nico Weber
b50dc04b3d wrap an rst file to 80 cols, to cycle bots 2019-12-06 17:28:02 -05:00
Craig Topper
08dfbd5919 [TargetLowering] Fix another potential FPE in expandFP_TO_UINT
D53794 introduced code to perform the FP_TO_UINT expansion via FP_TO_SINT in a way that would never expose floating-point exceptions in the intermediate steps. Unfortunately, I just noticed there is still a way this can happen. As discussed in D53794, the compiler now generates this sequence:

// Sel = Src < 0x8000000000000000
// Val = select Sel, Src, Src - 0x8000000000000000
// Ofs = select Sel, 0, 0x8000000000000000
// Result = fp_to_sint(Val) ^ Ofs
The problem is with the Src - 0x8000000000000000 expression. As I mentioned in the original review, that expression can never overflow or underflow if the original value is in range for FP_TO_UINT. But I missed that we can get an Inexact exception in the case where Src is a very small positive value. (In this case the result of the sub is ignored, but that doesn't help.)

Instead, I'd suggest to use the following sequence:

// Sel = Src < 0x8000000000000000
// FltOfs = select Sel, 0, 0x8000000000000000
// IntOfs = select Sel, 0, 0x8000000000000000
// Result = fp_to_sint(Val - FltOfs) ^ IntOfs
In the case where the value is already in range of FP_TO_SINT, we now simply compute Val - 0, which now definitely cannot trap (unless Val is a NaN in which case we'd want to trap anyway).

In the case where the value is not in range of FP_TO_SINT, but still in range of FP_TO_UINT, the sub can never be inexact, as Val is between 2^(n-1) and (2^n)-1, i.e. always has the 2^(n-1) bit set, and the sub is always simply clearing that bit.

There is a slight complication in the case where Val is a constant, so we know at compile time whether Sel is true or false. In that scenario, the old code would automatically optimize the sub away, while this no longer happens with the new code. Instead, I've added extra code to check for this case and then just fall back to FP_TO_SINT directly. (This seems to catch even slightly more cases.)

Original version of the patch by Ulrich Weigand. X86 changes added by Craig Topper

Differential Revision: https://reviews.llvm.org/D67105
2019-12-06 14:11:04 -08:00
Sanjay Patel
5bd1aece96 [InstSimplify] add tests for copysign with fneg operand; NFC 2019-12-06 16:23:44 -05:00
Teresa Johnson
717b67f012 [WPD] Remove unused parameter (NFC)
Remove unused parameter.
2019-12-06 13:14:21 -08:00