Commit Graph

6703 Commits

Author SHA1 Message Date
Vedant Kumar
7eb1cc47be [SelectionDAG] Consolidate (t|T)ransferDbgValues methods, NFC.
TransferDbgValues (capital 'T') is wired into ReplaceAllUsesWith, and
transferDbgValues (lowercase 't') is used elsewhere (e.g in Legalize).

Both functions should be doing the exact same thing. This patch
consolidates the logic into one place.

Differential Revision: https://reviews.llvm.org/D40104

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318448 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-16 19:50:24 +00:00
Guozhi Wei
a448ad72b2 [PPC] Change i32 constant in store instruction to i64
This patch changes all i32 constant in store instruction to i64 with truncation, to increase the chance that the referenced constant can be shared with other i64 constant.

Differential Revision: https://reviews.llvm.org/D39352



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318436 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-16 18:27:34 +00:00
Daniel Sanders
64b77007a6 [globalisel][tablegen] Generate rule coverage and use it to identify untested rules
Summary:
This patch adds a LLVM_ENABLE_GISEL_COV which, like LLVM_ENABLE_DAGISEL_COV,
causes TableGen to instrument the generated table to collect rule coverage
information. However, LLVM_ENABLE_GISEL_COV goes a bit further than
LLVM_ENABLE_DAGISEL_COV. The information is written to files
(${CMAKE_BINARY_DIR}/gisel-coverage-* by default). These files can then be
concatenated into ${LLVM_GISEL_COV_PREFIX}-all after which TableGen will
read this information and use it to emit warnings about untested rules.

This technique could also be used by SelectionDAG and can be further
extended to detect hot rules and give them priority over colder rules.

Usage:
* Enable LLVM_ENABLE_GISEL_COV in CMake
* Build the compiler and run some tests
* cat gisel-coverage-[0-9]* > gisel-coverage-all
* Delete lib/Target/*/*GenGlobalISel.inc*
* Build the compiler

Known issues:
* ${LLVM_GISEL_COV_PREFIX}-all must be generated as a manual
  step due to a lack of a portable 'cat' command. It should be the
  concatenation of all ${LLVM_GISEL_COV_PREFIX}-[0-9]* files.
* There's no mechanism to discard coverage information when the ruleset
  changes

Depends on D39742

Reviewers: ab, qcolombet, t.p.northover, aditya_nandakumar, rovka

Reviewed By: rovka

Subscribers: vsk, arsenm, nhaehnle, mgorny, kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D39747

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318356 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-16 00:46:35 +00:00
Aditya Nandakumar
e6aaf10a30 [GISel][NFC]: Move getOpcodeDef from the LegalizationArtifactCombiner into GlobalISel/Utils for use elsewhere
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318350 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-15 23:45:04 +00:00
NAKAMURA Takumi
adf7d53473 GISelWorkList.h: Fix -fmodules build in rL318210.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318275 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-15 07:34:35 +00:00
Aditya Nandakumar
0053d0421c [GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE

Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.

Updated legalization algorithm to roughly the following pseudo code.

WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);

do {
  for (Inst in Insts)
         legalizeInstrStep(Inst, Insts, Artifacts);
  for (Artifact in Artifacts)
         tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());

Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318210 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-14 22:42:19 +00:00
Hans Wennborg
5765d84997 Rename CountingFunctionInserter and use for both mcount and cygprofile calls, before and after inlining
Clang implements the -finstrument-functions flag inherited from GCC, which
inserts calls to __cyg_profile_func_{enter,exit} on function entry and exit.

This is useful for getting a trace of how the functions in a program are
executed. Normally, the calls remain even if a function is inlined into another
function, but it is useful to be able to turn this off for users who are
interested in a lower-level trace, i.e. one that reflects what functions are
called post-inlining. (We use this to generate link order files for Chromium.)

LLVM already has a pass for inserting similar instrumentation calls to
mcount(), which it does after inlining. This patch renames and extends that
pass to handle calls both to mcount and the cygprofile functions, before and/or
after inlining as controlled by function attributes.

Differential Revision: https://reviews.llvm.org/D39287

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318195 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-14 21:09:45 +00:00
Alex Bradbury
1715109e25 Set hasSideEffects=0 for TargetOpcode::{CFI_INSTRUCTION,EH_LABEL,GC_LABEL,ANNOTATION_LABEL}
D37065 (committed as rL317674) explicitly set hasSideEffects for all 
TargetOpcode::* instructions where it was inferred previously. This is a 
follow-up to that patch, setting hasSideEffects=0 for CFI_INSTRUCTION, 
EH_LABEL, GC_LABEL and ANNOTATION_LABEL. All LLVM tests pass after this 
change.

This patch also modifies MachineInstr::isLabel returns true for a 
TargetOpcode::ANNOTATION_LABEL, which ensures that an annotation label won't 
be incorrectly considered safe to move.

Differential Revision: https://reviews.llvm.org/D39941


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318174 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-14 19:16:08 +00:00
Daniel Sanders
8f5a591f29 [globalisel][tablegen] Import signextload and zeroextload.
Allow a pattern rewriter to be installed in CodeGenDAGPatterns and use it to
correct situations where SelectionDAG and GlobalISel disagree on
representation. For example, it would rewrite:
  (sextload:i32 $ptr)<<unindexedload>><<sextload>><<sextloadi16>
to:
  (sext:i32 (load:i16 $ptr)<<unindexedload>>)

I'd have preferred to replace the fragments and have the expansion happen
naturally as part of PatFrag expansion but the type inferencing system can't
cope with loads of types narrower than those mentioned in register classes.
This is because the SDTCisInt's on the sext constrain both the result and
operand to the 'legal' integer types (where legal is defined as 'a register
class can contain the type') which immediately rules the narrower types out.
Several targets (those with only one legal integer type) would then go on to
crash on the SDTCisOpSmallerThanOp<> when it removes all the possible types
for the result of the extend.

Also, improve isObviouslySafeToFold() slightly to automatically return true for
neighbouring instructions. There can't be any re-ordering problems if
re-ordering isn't happenning. We'll need to improve it further to handle
sign/zero-extending loads when the extend and load aren't immediate neighbours
though.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317971 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-11 03:23:44 +00:00
Adrian Prantl
13c8bc9216 Preserve debug info when DAG-combinging (zext (truncate x)) -> (and x, mask).
rdar://problem/27139077

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317825 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-09 19:50:20 +00:00
Andrew V. Tischenko
a5b99ed522 Add -print-schedule scheduling comments to inline asm.
Differential Revision: https://reviews.llvm.org/D39728


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317782 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-09 12:45:40 +00:00
Craig Topper
20c675a70a [X86] X86MaskedGatherSDNode shouldn't inherit from MaskedGatherScatterSDNode
The classof implementation in MaskedGatherScatterSDNode doesn't consider X86MaskedGatherSDNode so its misleading.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317733 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-08 22:26:41 +00:00
Dan Gohman
b5e0bec282 Add an @llvm.sideeffect intrinsic
This patch implements Chandler's idea [0] for supporting languages that
require support for infinite loops with side effects, such as Rust, providing
part of a solution to bug 965 [1].

Specifically, it adds an `llvm.sideeffect()` intrinsic, which has no actual
effect, but which appears to optimization passes to have obscure side effects,
such that they don't optimize away loops containing it. It also teaches
several optimization passes to ignore this intrinsic, so that it doesn't
significantly impact optimization in most cases.

As discussed on llvm-dev [2], this patch is the first of two major parts.
The second part, to change LLVM's semantics to have defined behavior
on infinite loops by default, with a function attribute for opting into
potential-undefined-behavior, will be implemented and posted for review in
a separate patch.

[0] http://lists.llvm.org/pipermail/llvm-dev/2015-July/088103.html
[1] https://bugs.llvm.org/show_bug.cgi?id=965
[2] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118632.html

Differential Revision: https://reviews.llvm.org/D38336


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317729 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-08 21:59:51 +00:00
Reid Kleckner
bfc1e953bc Revert "Correct dwarf unwind information in function epilogue for X86"
This reverts r317579, originally committed as r317100.

There is a design issue with marking CFI instructions duplicatable. Not
all targets support the CFIInstrInserter pass, and targets like Darwin
can't cope with duplicated prologue setup CFI instructions. The compact
unwind info emission fails.

When the following code is compiled for arm64 on Mac at -O3, the CFI
instructions end up getting tail duplicated, which causes compact unwind
info emission to fail:
  int a, c, d, e, f, g, h, i, j, k, l, m;
  void n(int o, int *b) {
    if (g)
      f = 0;
    for (; f < o; f++) {
      m = a;
      if (l > j * k > i)
        j = i = k = d;
      h = b[c] - e;
    }
  }

We get assembly that looks like this:
; BB#1:                                 ; %if.then
Lloh3:
	adrp	x9, _f@GOTPAGE
Lloh4:
	ldr	x9, [x9, _f@GOTPAGEOFF]
	mov	 w8, wzr
Lloh5:
	str		wzr, [x9]
	stp	x20, x19, [sp, #-16]!   ; 8-byte Folded Spill
	.cfi_def_cfa_offset 16
	.cfi_offset w19, -8
	.cfi_offset w20, -16
	cmp		w8, w0
	b.lt	LBB0_3
	b	LBB0_7
LBB0_2:                                 ; %entry.if.end_crit_edge
Lloh6:
	adrp	x8, _f@GOTPAGE
Lloh7:
	ldr	x8, [x8, _f@GOTPAGEOFF]
Lloh8:
	ldr		w8, [x8]
	stp	x20, x19, [sp, #-16]!   ; 8-byte Folded Spill
	.cfi_def_cfa_offset 16
	.cfi_offset w19, -8
	.cfi_offset w20, -16
	cmp		w8, w0
	b.ge	LBB0_7
LBB0_3:                                 ; %for.body.lr.ph

Note the multiple .cfi_def* directives. Compact unwind info emission
can't handle that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317726 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-08 21:31:14 +00:00
David Blaikie
48319238e4 Target/TargetInstrInfo.h -> CodeGen/TargetInstrInfo.h to match layering
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317647 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-08 01:01:31 +00:00
Petar Jovanovic
8cec6c4916 Reland "Correct dwarf unwind information in function epilogue for X86"
Reland r317100 with minor fix regarding ComputeCommonTailLength function in
BranchFolding.cpp. Skipping top CFI instructions block needs to executed on
several more return points in ComputeCommonTailLength().

Original r317100 message:

"Correct dwarf unwind information in function epilogue for X86"

This patch aims to provide correct dwarf unwind information in function
epilogue for X86.

It consists of two parts. The first part inserts CFI instructions that set
appropriate cfa offset and cfa register in emitEpilogue() in
X86FrameLowering. This part is X86 specific.

The second part is platform independent and ensures that:

- CFI instructions do not affect code generation
- Unwind information remains correct when a function is modified by
  different passes. This is done in a late pass by analyzing information
  about cfa offset and cfa register in BBs and inserting additional CFI
  directives where necessary.

Changed CFI instructions so that they:

- are duplicable
- are not counted as instructions when tail duplicating or tail merging
- can be compared as equal

Added CFIInstrInserter pass:

- analyzes each basic block to determine cfa offset and register valid at
  its entry and exit
- verifies that outgoing cfa offset and register of predecessor blocks match
  incoming values of their successors
- inserts additional CFI directives at basic block beginning to correct the
  rule for calculating CFA

Having CFI instructions in function epilogue can cause incorrect CFA
calculation rule for some basic blocks. This can happen if, due to basic
block reordering, or the existence of multiple epilogue blocks, some of the
blocks have wrong cfa offset and register values set by the epilogue block
above them.

CFIInstrInserter is currently run only on X86, but can be used by any target
that implements support for adding CFI instructions in epilogue.

Patch by Violeta Vukobrat.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317579 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-07 14:40:27 +00:00
Kristof Beyls
b79469ca2f [GlobalISel] Enable legalizing non-power-of-2 sized types.
This changes the interface of how targets describe how to legalize, see
the below description.

1. Interface for targets to describe how to legalize.

In GlobalISel, the API in the LegalizerInfo class is the main interface
for targets to specify which types are legal for which operations, and
what to do to turn illegal type/operation combinations into legal ones.

For each operation the type sizes that can be legalized without having
to change the size of the type are specified with a call to setAction.
This isn't different to how GlobalISel worked before. For example, for a
target that supports 32 and 64 bit adds natively:

  for (auto Ty : {s32, s64})
    setAction({G_ADD, 0, s32}, Legal);

or for a target that needs a library call for a 32 bit division:

  setAction({G_SDIV, s32}, Libcall);

The main conceptual change to the LegalizerInfo API, is in specifying
how to legalize the type sizes for which a change of size is needed. For
example, in the above example, how to specify how all types from i1 to
i8388607 (apart from s32 and s64 which are legal) need to be legalized
and expressed in terms of operations on the available legal sizes
(again, i32 and i64 in this case). Before, the implementation only
allowed specifying power-of-2-sized types (e.g. setAction({G_ADD, 0,
s128}, NarrowScalar).  A worse limitation was that if you'd wanted to
specify how to legalize all the sized types as allowed by the LLVM-IR
LangRef, i1 to i8388607, you'd have to call setAction 8388607-3 times
and probably would need a lot of memory to store all of these
specifications.

Instead, the legalization actions that need to change the size of the
type are specified now using a "SizeChangeStrategy".  For example:

   setLegalizeScalarToDifferentSizeStrategy(
       G_ADD, 0, widenToLargerAndNarrowToLargest);

This example indicates that for type sizes for which there is a larger
size that can be legalized towards, do it by Widening the size.
For example, G_ADD on s17 will be legalized by first doing WidenScalar
to make it s32, after which it's legal.
The "NarrowToLargest" indicates what to do if there is no larger size
that can be legalized towards. E.g. G_ADD on s92 will be legalized by
doing NarrowScalar to s64.

Another example, taken from the ARM backend is:
   for (unsigned Op : {G_SDIV, G_UDIV}) {
     setLegalizeScalarToDifferentSizeStrategy(Op, 0,
         widenToLargerTypesUnsupportedOtherwise);
     if (ST.hasDivideInARMMode())
       setAction({Op, s32}, Legal);
     else
       setAction({Op, s32}, Libcall);
   }

For this example, G_SDIV on s8, on a target without a divide
instruction, would be legalized by first doing action (WidenScalar,
s32), followed by (Libcall, s32).

The same principle is also followed for when the number of vector lanes
on vector data types need to be changed, e.g.:

   setAction({G_ADD, LLT::vector(8, 8)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(16, 8)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(4, 16)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(8, 16)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(2, 32)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(4, 32)}, LegalizerInfo::Legal);
   setLegalizeVectorElementToDifferentSizeStrategy(
       G_ADD, 0, widenToLargerTypesUnsupportedOtherwise);

As currently implemented here, vector types are legalized by first
making the vector element size legal, followed by then making the number
of lanes legal. The strategy to follow in the first step is set by a
call to setLegalizeVectorElementToDifferentSizeStrategy, see example
above.  The strategy followed in the second step
"moreToWiderTypesAndLessToWidest" (see code for its definition),
indicating that vectors are widened to more elements so they map to
natively supported vector widths, or when there isn't a legal wider
vector, split the vector to map it to the widest vector supported.

Therefore, for the above specification, some example legalizations are:
  * getAction({G_ADD, LLT::vector(3, 3)})
    returns {WidenScalar, LLT::vector(3, 8)}
  * getAction({G_ADD, LLT::vector(3, 8)})
    then returns {MoreElements, LLT::vector(8, 8)}
  * getAction({G_ADD, LLT::vector(20, 8)})
    returns {FewerElements, LLT::vector(16, 8)}


2. Key implementation aspects.

How to legalize a specific (operation, type index, size) tuple is
represented by mapping intervals of integers representing a range of
size types to an action to take, e.g.:

       setScalarAction({G_ADD, LLT:scalar(1)},
                       {{1, WidenScalar},  // bit sizes [ 1, 31[
                        {32, Legal},       // bit sizes [32, 33[
                        {33, WidenScalar}, // bit sizes [33, 64[
                        {64, Legal},       // bit sizes [64, 65[
                        {65, NarrowScalar} // bit sizes [65, +inf[
                       });

Please note that most of the code to do the actual lowering of
non-power-of-2 sized types is currently missing, this is just trying to
make it possible for targets to specify what is legal, and how non-legal
types should be legalized.  Probably quite a bit of further work is
needed in the actual legalizing and the other passes in GlobalISel to
support non-power-of-2 sized types.

I hope the documentation in LegalizerInfo.h and the examples provided in the
various {Target}LegalizerInfo.cpp and LegalizerInfoTest.cpp explains well
enough how this is meant to be used.

This drops the need for LLT::{half,double}...Size().


Differential Revision: https://reviews.llvm.org/D30529



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317560 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-07 10:34:34 +00:00
Bjorn Pettersson
4cbab70b62 [MIRPrinter] Use %subreg.xxx syntax for subregister index operands
Summary:
Print %subreg.<subregidxname> instead of just the subregister
index when printing immediate operands corresponding to subreg
indices in INSERT_SUBREG, EXTRACT_SUBREG, SUBREG_TO_REG and
REG_SEQUENCE.

Reviewers: qcolombet, MatzeB

Reviewed By: MatzeB

Subscribers: nhaehnle, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D39696

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317513 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-06 21:46:06 +00:00
David Blaikie
803f827385 Move TargetFrameLowering.h to CodeGen where it's implemented
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.

This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317379 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-03 22:32:11 +00:00
David Blaikie
ceb5b1b434 Modularize: Include some required headers
DenseMaps require the definition of a type to be available when using a
pointer to that type as a key to know how many bits are available for
tombstone/etc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317360 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-03 20:24:19 +00:00
Clement Courbet
3d456013b6 re-land [ExpandMemCmp] Split ExpandMemCmp from CodeGen into its own pass."
Fix undefined references: ExpandMemCmp belongs to CodeGen/, not Scalar/.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317318 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-03 12:12:27 +00:00
Hiroshi Yamauchi
dd33e177dd Irreducible loop metadata for more accurate block frequency under PGO.
Summary:
Currently the block frequency analysis is an approximation for irreducible
loops.

The new irreducible loop metadata is used to annotate the irreducible loop
headers with their header weights based on the PGO profile (currently this is
approximated to be evenly weighted) and to help improve the accuracy of the
block frequency analysis for irreducible loops.

This patch is a basic support for this.

Reviewers: davidxl

Reviewed By: davidxl

Subscribers: mehdi_amini, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D39028

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317278 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-02 22:26:51 +00:00
Petar Jovanovic
5616b72dcf Revert "Correct dwarf unwind information in function epilogue for X86"
This reverts r317100 as it introduced sanitizer-x86_64-linux-autoconf
buildbot failure (build #15606).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317136 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01 23:05:52 +00:00
Daniel Sanders
4d7894c6d8 [globalisel][tablegen] Add support for multi-insn emission
The importer will now accept nested instructions in the result pattern such as
(ADDWrr $a, (SUBWrr $b, $c)). This is only valid when the nested instruction
def's a single vreg and the parent instruction consumes a single vreg where a
nested instruction is specified. The importer will automatically create a vreg
to connect the two using the type information from the pattern. This vreg will
be constrained to the register classes given in the instruction definitions*.

* REG_SEQUENCE is explicitly rejected because of this. The definition doesn't
  constrain to a register class and it therefore needs special handling.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317117 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01 19:57:57 +00:00
Petar Jovanovic
bb38652ad4 Correct dwarf unwind information in function epilogue for X86
This patch aims to provide correct dwarf unwind information in function
epilogue for X86.

It consists of two parts. The first part inserts CFI instructions that set
appropriate cfa offset and cfa register in emitEpilogue() in
X86FrameLowering. This part is X86 specific.

The second part is platform independent and ensures that:

- CFI instructions do not affect code generation
- Unwind information remains correct when a function is modified by
  different passes. This is done in a late pass by analyzing information
  about cfa offset and cfa register in BBs and inserting additional CFI
  directives where necessary.

Changed CFI instructions so that they:

- are duplicable
- are not counted as instructions when tail duplicating or tail merging
- can be compared as equal

Added CFIInstrInserter pass:

- analyzes each basic block to determine cfa offset and register valid at
  its entry and exit
- verifies that outgoing cfa offset and register of predecessor blocks match
  incoming values of their successors
- inserts additional CFI directives at basic block beginning to correct the
  rule for calculating CFA

Having CFI instructions in function epilogue can cause incorrect CFA
calculation rule for some basic blocks. This can happen if, due to basic
block reordering, or the existence of multiple epilogue blocks, some of the
blocks have wrong cfa offset and register values set by the epilogue block
above them.

CFIInstrInserter is currently run only on X86, but can be used by any target
that implements support for adding CFI instructions in epilogue.


Patch by Violeta Vukobrat.

Differential Revision: https://reviews.llvm.org/D35844


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317100 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01 16:04:11 +00:00
NAKAMURA Takumi
598658d792 Fix warnings discovered by rL317076. [-Wunused-private-field]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317091 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01 13:47:55 +00:00
NAKAMURA Takumi
049a66484d llvm/CodeGen/GlobalISel/InstructionSelectorImpl.h: Fix -fmodules build introduced in rL316715.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316743 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-27 05:45:11 +00:00
Sean Fertile
53b3cd421e Add subclass data to the FoldingSetNode for MemIntrinsicSDNodes.
Not having the subclass data on an MemIntrinsicSDNodes means it was possible
to try to fold 2 nodes with the same operands but differing MMO flags. This
would trip an assertion when trying to refine the alignment between the 2
MachineMemOperands.

Differential Revision: https://reviews.llvm.org/D38898

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316737 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-27 04:02:51 +00:00
David Blaikie
7be6b37802 InstructionSelectorImpl.h: Modularize/remove ODR violations by using a static member function to expose the debug name
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316715 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-26 23:39:54 +00:00
Aditya Nandakumar
6b9f2f6345 [GISel]: Missed checking if it's okay to create a G_CONSTANT of DstTy in the legalizationCombiner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316694 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-26 20:13:54 +00:00
Aditya Nandakumar
ca37830df0 Make the combiner check if shifts are legal before creating them
Summary: Make sure shifts are legal/specified by the legalizerinfo before creating it

Reviewers: qcolombet, dsanders, rovka, t.p.northover

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D39264

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316602 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-25 18:49:18 +00:00
Adrian Prantl
4a39ef301e Implement salavageDebugInfo functionality for SelectionDAG.
Similar to how llvm::salvagDebugInfo hooks into InstCombine, this adds
a hook that can be invoked before an SDNode that is associated with an
SDDbgValue is erased to capture the effect of the deleted node in a
DIExpression.

The motivating example is an SDDebugValue attached to an ADD operation
that gets folded into a LOAD+OFFSET operation.

rdar://problem/32121503

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316525 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-24 22:55:12 +00:00
David Blaikie
e3ed1e8dc7 RegisterUsageInfo.h: Add missing header for complete type needed for DenseMap traits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316504 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-24 21:29:10 +00:00
Omer Paparo Bivas
1be670d526 [MC] Adding code padding for performance stability - infrastructure. NFC.
Infrastructure designed for padding code with nop instructions in key places such that preformance improvement will be achieved.
The infrastructure is implemented such that the padding is done in the Assembler after the layout is done and all IPs and alignments are known.
This patch by itself in a NFC. Future patches will make use of this infrastructure to implement required policies for code padding.

Reviewers:
aaboud
zvi
craig.topper
gadi.haber

Differential revision: https://reviews.llvm.org/D34393

Change-Id: I92110d0c0a757080a8405636914a93ef6f8ad00e

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316413 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-24 06:16:03 +00:00
Daniel Sanders
6affa236cf [globalisel][tablegen] Import stores and allow GISel to automatically substitute zero regs like WZR/XZR/$zero.
This patch enables the import of stores. Unfortunately, doing so by itself,
loses an optimization where storing 0 to memory makes use of WZR/XZR.

To mitigate this, this patch also introduces a new feature that allows register
operands to nominate a zero register. When this is done, GlobalISel will
substitute (G_CONSTANT 0) with the nominated register automatically. This
is currently configured to only apply to the stores.

Applying it to GPR32/GPR64 register classes in general will be done after
review see (https://reviews.llvm.org/D39150).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316360 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-23 18:19:24 +00:00
Marina Yatsina
b76f989d6b Add logic to greedy reg alloc to avoid bad eviction chains
This fixes bugzilla 26810
https://bugs.llvm.org/show_bug.cgi?id=26810

This is intended to prevent sequences like:
movl %ebp, 8(%esp) # 4-byte Spill
movl %ecx, %ebp
movl %ebx, %ecx
movl %edi, %ebx
movl %edx, %edi
cltd
idivl %esi
movl %edi, %edx
movl %ebx, %edi
movl %ecx, %ebx
movl %ebp, %ecx
movl 16(%esp), %ebp # 4 - byte Reload

Such sequences are created in 2 scenarios:

Scenario #1:
vreg0 is evicted from physreg0 by vreg1
Evictee vreg0 is intended for region splitting with split candidate physreg0 (the reg vreg0 was evicted from)
Region splitting creates a local interval because of interference with the evictor vreg1 (normally region spliiting creates 2 interval, the "by reg" and "by stack" intervals. Local interval created when interference occurs.)
one of the split intervals ends up evicting vreg2 from physreg1
Evictee vreg2 is intended for region splitting with split candidate physreg1
one of the split intervals ends up evicting vreg3 from physreg2 etc.. until someone spills

Scenario #2
vreg0 is evicted from physreg0 by vreg1
vreg2 is evicted from physreg2 by vreg3 etc
Evictee vreg0 is intended for region splitting with split candidate physreg1
Region splitting creates a local interval because of interference with the evictor vreg1
one of the split intervals ends up evicting back original evictor vreg1 from physreg0 (the reg vreg0 was evicted from)
Another evictee vreg2 is intended for region splitting with split candidate physreg1
one of the split intervals ends up evicting vreg3 from physreg2 etc.. until someone spills

As compile time was a concern, I've added a flag to control weather we do cost calculations for local intervals we expect to be created (it's on by default for X86 target, off for the rest).

Differential Revision: https://reviews.llvm.org/D35816

Change-Id: Id9411ff7bbb845463d289ba2ae97737a1ee7cc39

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316295 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-22 17:59:38 +00:00
Krzysztof Parzyszek
26843fd82c [Packetizer] Add function to check for aliasing between instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316243 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-20 22:08:40 +00:00
Daniel Sanders
d83b5d463d [globalisel][tablegen] Fix small spelling nits. NFC
ComplexRendererFn -> ComplexRendererFns
Corrected a couple lingering references to tied operands that were missed.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316237 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-20 20:55:29 +00:00
Yichao Yu
f500b96fb9 Fix FaultMaps crash when the out streamer is reused
Summary:
Make sure the map is cleared before processing a new module. Similar to what is done on `StackMaps`.

This issue is similar to D38588, though this time for FaultMaps (on x86) rather than ARM/AArch64. Other than possible mixing of information between modules, the crash is caused by the pointers values in the map that was allocated by the bump pointer allocator that is unwinded when emitting the next file. This issue has been around since 3.8.

This issue is likely much harder to write a test for since AFAICT it requires emitting something much more compilcated (and possibly real code) instead of just some random bytes.

Reviewers: skatkov, sanjoy

Reviewed By: skatkov, sanjoy

Subscribers: sanjoy, aemerson, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D38924

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315990 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-17 11:44:34 +00:00
Krzysztof Parzyszek
de6f815369 Replace make_range in MachineRegisterInfo with ArrayRef, NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315938 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-16 21:19:40 +00:00
Krzysztof Parzyszek
7b72f3902c Add iterator range MachineRegisterInfo::liveins(), adopt users, NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315927 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-16 19:08:41 +00:00
Daniel Sanders
4175d2c7f0 Re-commit r315885: [globalisel][tblgen] Add support for iPTR and implement am_unscaled* and am_indexed*
Summary:
iPTR is a pointer of subtarget-specific size to any address space. Therefore
type checks on this size derive the SizeInBits from a subtarget hook.

At this point, we can import the simplests G_LOAD rules and select load
instructions using them. Further patches will support for the predicates to
enable additional loads as well as the stores.

The previous commit failed on MSVC due to a failure to convert an
initializer_list to a std::vector. Hopefully, MSVC will accept this version.

Depends on D37457

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: kristof.beyls, javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37458



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315887 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-16 03:36:29 +00:00
Daniel Sanders
196db93f65 Revert r315885: [globalisel][tblgen] Add support for iPTR and implement am_unscaled* and am_indexed*
MSVC doesn't like one of the constructors.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315886 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-16 02:15:39 +00:00
Daniel Sanders
728d43b28f [globalisel][tblgen] Add support for iPTR and implement am_unscaled* and am_indexed*
Summary:
iPTR is a pointer of subtarget-specific size to any address space. Therefore
type checks on this size derive the SizeInBits from a subtarget hook.

At this point, we can import the simplests G_LOAD rules and select load
instructions using them. Further patches will support for the predicates to
enable additional loads as well as the stores.

Depends on D37457

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: kristof.beyls, javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37458

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315885 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-16 01:16:35 +00:00
Daniel Sanders
508747d418 [globalisel][tablegen] Implement unindexed load, non-extending load, and MemVT checks
Summary:
This includes some context-sensitivity in the MVT to LLT conversion so that
pointer types are tested correctly.
FIXME: I'm not happy with the way this is done since everything is a
       special-case. I've yet to find a reasonable way to implement it.

select-load.mir fails because <1 x s64> loads in tablegen get priority over s64
loads. This is fixed in the next patch and as such they should be committed
together, I've posted them separately to help with the review.

Depends on D37456

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Subscribers: kristof.beyls, javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37457

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315884 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-16 00:56:30 +00:00
Daniel Sanders
af1e278b91 Re-commit r315863: [globalisel][tablegen] Import ComplexPattern when used as an operator
Summary:
It's possible for a ComplexPattern to be used as an operator in a match
pattern. This is used by the load/store patterns in AArch64 to name the
suboperands returned by ComplexPattern predicate so that they can be broken
apart and referenced independently in the result pattern.

This patch adds support for this in order to enable the import of load/store
patterns.

Depends on D37445

Hopefully fixed the ambiguous constructor that a large number of bots reported.

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D37456


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315869 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-15 18:22:54 +00:00
Daniel Sanders
7eb649c303 Revert r315863: [globalisel][tablegen] Import ComplexPattern when used as an operator
A large number of bots are failing on an ambiguous constructor call.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315866 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-15 17:51:07 +00:00
Daniel Sanders
cd3c7b27fe [globalisel][tablegen] Import ComplexPattern when used as an operator
Summary:
It's possible for a ComplexPattern to be used as an operator in a match
pattern. This is used by the load/store patterns in AArch64 to name the
suboperands returned by ComplexPattern predicate so that they can be broken
apart and referenced independently in the result pattern.

This patch adds support for this in order to enable the import of load/store
patterns.

Depends on D37445

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D37456

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315863 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-15 17:03:36 +00:00
Aaron Ballman
1d03d382c1 Reverting r315590; it did not include changes for llvm-tblgen, which is causing link errors for several people.
Error LNK2019 unresolved external symbol "public: void __cdecl `anonymous namespace'::MatchableInfo::dump(void)const " (?dump@MatchableInfo@?A0xf4f1c304@@QEBAXXZ) referenced in function "public: void __cdecl `anonymous namespace'::AsmMatcherEmitter::run(class llvm::raw_ostream &)" (?run@AsmMatcherEmitter@?A0xf4f1c304@@QEAAXAEAVraw_ostream@llvm@@@Z) llvm-tblgen D:\llvm\2017\utils\TableGen\AsmMatcherEmitter.obj 1


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315854 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-15 14:32:27 +00:00
Daniel Sanders
186cd4a192 [globalisel][tablegen] Map ld and st to G_LOAD and G_STORE. NFC
Summary:
There is an important mismatch between ISD::LOAD and G_LOAD (and likewise for
ISD::STORE and G_STORE). In SelectionDAG, ISD::LOAD is a non-atomic load
and atomic loads are handled by a separate node. However, this is not true of
GlobalISel's G_LOAD. For G_LOAD, the MachineMemOperand indicates the atomicity
of the operation. As a result, this mapping must also add a predicate that
checks for non-atomic MachineMemOperands.

This is NFC since these nodes always have predicates in practice and are
therefore always rejected at the moment.

Depends on D37443

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: kristof.beyls, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37445

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315843 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-15 02:41:12 +00:00