51 Commits

Author SHA1 Message Date
Amir Ayupov
82bc33ea3f
[BOLT] Fix unconditional output of boltedcollection in merge-fdata (#78653)
Fix the bug where merge-fdata unconditionally outputs boltedcollection 
line, regardless of whether input files have it set.

Test Plan:
Added bolt/test/X86/merge-fdata-nobat-mode.test which fails without this
fix.
2024-01-18 19:44:16 -08:00
David Green
7850c94b86 [NFC] sentinal -> sentinel 2024-01-16 17:22:06 +00:00
spupyrev
eecd41aa09 Revert "Rebase: [Facebook] [MC] Introduce NeverAlign fragment type"
This reverts commit 6d0528636ae54fba75938a79ae7a98dfcc949f72.
2022-07-11 09:50:47 -07:00
Rafael Auler
6d0528636a Rebase: [Facebook] [MC] Introduce NeverAlign fragment type
Summary:
Introduce NeverAlign fragment type.

The intended usage of this fragment is to insert it before a pair of
macro-op fusion eligible instructions. NeverAlign fragment ensures that
the next fragment (first instruction in the pair) does not end at a
given alignment boundary by emitting a minimal size nop if necessary.

In effect, it ensures that a pair of macro-fusible instructions is not
split by a given alignment boundary, which is a precondition for
macro-op fusion in modern Intel Cores (64B = cache line size, see Intel
Architecture Optimization Reference Manual, 2.3.2.1 Legacy Decode
Pipeline: Macro-Fusion).

This patch introduces functionality used by BOLT when emitting code with
MacroFusion alignment already in place.

The use case is different from BoundaryAlign and instruction bundling:
- BoundaryAlign can be extended to perform the desired alignment for the
first instruction in the macro-op fusion pair (D101817). However, this
approach has higher overhead due to reliance on relaxation as
BoundaryAlign requires in the general case - see
https://reviews.llvm.org/D97982#2710638.
- Instruction bundling: the intent of NeverAlign fragment is to prevent
the first instruction in a pair ending at a given alignment boundary, by
inserting at most one minimum size nop. It's OK if either instruction
crosses the cache line. Padding both instructions using bundles to not
cross the alignment boundary would result in excessive padding. There's
no straightforward way to request instruction bundling to avoid a given
end alignment for the first instruction in the bundle.

LLVM: https://reviews.llvm.org/D97982

Manual rebase conflict history:
https://phabricator.intern.facebook.com/D30142613

Test Plan: sandcastle

Reviewers: #llvm-bolt

Subscribers: phabricatorlinter

Differential Revision: https://phabricator.intern.facebook.com/D31361547
2022-07-11 09:31:52 -07:00
Guillaume Chatelet
412c788ab0 [NFC][Alignment] Use Align in MCAlignFragment 2022-06-15 12:31:00 +00:00
Leonard Grey
5d57578a4e [MC] Recursively calculate symbol offset
This is speculative since I'm not sure if there's some implicit contract that a
variable symbol must not have another variable symbol in its evaluation tree.

Downstream bug: https://bugs.chromium.org/p/chromium/issues/detail?id=471146#c23.

Test is based on alias.s (removed checks since we just need to know it didn't
crash).

Differential Revision: https://reviews.llvm.org/D109109
2021-10-20 14:29:43 -04:00
Hongtao Yu
705a4c149d [CSSPGO] Pseudo probe encoding and emission.
This change implements pseudo probe encoding and emission for CSSPGO. Please see RFC here for more context: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s

Pseudo probes are in the form of intrinsic calls on IR/MIR but they do not turn into any machine instructions. Instead they are emitted into the binary as a piece of data in standalone sections.  The probe-specific sections are not needed to be loaded into memory at execution time, thus they do not incur a runtime overhead. 

**ELF object emission**

The binary data to emit are organized as two ELF sections, i.e, the `.pseudo_probe_desc` section and the `.pseudo_probe` section. The `.pseudo_probe_desc` section stores a function descriptor for each function and the `.pseudo_probe` section stores the actual probes, each fo which corresponds to an IR basic block or an IR function callsite. A function descriptor is stored as a module-level metadata during the compilation and is serialized into the object file during object emission.

Both the probe descriptors and pseudo probes can be emitted into a separate ELF section per function to leverage the linker for deduplication.  A `.pseudo_probe` section shares the same COMDAT group with the function code so that when the function is dead, the probes are dead and disposed too. On the contrary, a `.pseudo_probe_desc` section has its own COMDAT group. This is because even if a function is dead, its probes may be inlined into other functions and its descriptor is still needed by the profile generation tool.

The format of `.pseudo_probe_desc` section looks like:

```
.section   .pseudo_probe_desc,"",@progbits
.quad   6309742469962978389  // Func GUID
.quad   4294967295           // Func Hash
.byte   9                    // Length of func name
.ascii  "_Z5funcAi"          // Func name
.quad   7102633082150537521
.quad   138828622701
.byte   12
.ascii  "_Z8funcLeafi"
.quad   446061515086924981
.quad   4294967295
.byte   9
.ascii  "_Z5funcBi"
.quad   -2016976694713209516
.quad   72617220756
.byte   7
.ascii  "_Z3fibi"
```

For each `.pseudoprobe` section, the encoded binary data consists of a single function record corresponding to an outlined function (i.e, a function with a code entry in the `.text` section). A function record has the following format :

```
FUNCTION BODY (one for each outlined function present in the text section)
    GUID (uint64)
        GUID of the function
    NPROBES (ULEB128)
        Number of probes originating from this function.
    NUM_INLINED_FUNCTIONS (ULEB128)
        Number of callees inlined into this function, aka number of
        first-level inlinees
    PROBE RECORDS
        A list of NPROBES entries. Each entry contains:
          INDEX (ULEB128)
          TYPE (uint4)
            0 - block probe, 1 - indirect call, 2 - direct call
          ATTRIBUTE (uint3)
            reserved
          ADDRESS_TYPE (uint1)
            0 - code address, 1 - address delta
          CODE_ADDRESS (uint64 or ULEB128)
            code address or address delta, depending on ADDRESS_TYPE
    INLINED FUNCTION RECORDS
        A list of NUM_INLINED_FUNCTIONS entries describing each of the inlined
        callees.  Each record contains:
          INLINE SITE
            GUID of the inlinee (uint64)
            ID of the callsite probe (ULEB128)
          FUNCTION BODY
            A FUNCTION BODY entry describing the inlined function.
```

To support building a context-sensitive profile, probes from inlinees are grouped by their inline contexts. An inline context is logically a call path through which a callee function lands in a caller function. The probe emitter builds an inline tree based on the debug metadata for each outlined function in the form of a trie tree. A tree root is the outlined function. Each tree edge stands for a callsite where inlining happens. Pseudo probes originating from an inlinee function are stored in a tree node and the tree path starting from the root all the way down to the tree node is the inline context of the probes. The emission happens on the whole tree top-down recursively. Probes of a tree node will be emitted altogether with their direct parent edge. Since a pseudo probe corresponds to a real code address, for size savings, the address is encoded as a delta from the previous probe except for the first probe. Variant-sized integer encoding, aka LEB128, is used for address delta and probe index.

**Assembling**

Pseudo probes can be printed as assembly directives alternatively. This allows for good assembly code readability and also provides a view of how optimizations and pseudo probes affect each other, especially helpful for diff time assembly analysis.

A pseudo probe directive has the following operands in order: function GUID, probe index, probe type, probe attributes and inline context. The directive is generated by the compiler and can be parsed by the assembler to form an encoded `.pseudoprobe` section in the object file.

A example assembly looks like:

```
foo2: # @foo2
# %bb.0: # %bb0
pushq %rax
testl %edi, %edi
.pseudoprobe 837061429793323041 1 0 0
je .LBB1_1
# %bb.2: # %bb2
.pseudoprobe 837061429793323041 6 2 0
callq foo
.pseudoprobe 837061429793323041 3 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
.LBB1_1: # %bb1
.pseudoprobe 837061429793323041 5 1 0
callq *%rsi
.pseudoprobe 837061429793323041 2 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
# -- End function
.section .pseudo_probe_desc,"",@progbits
.quad 6699318081062747564
.quad 72617220756
.byte 3
.ascii "foo"
.quad 837061429793323041
.quad 281547593931412
.byte 4
.ascii "foo2"
```

With inlining turned on, the assembly may look different around %bb2 with an inlined probe:

```
# %bb.2:                                # %bb2
.pseudoprobe    837061429793323041 3 0
.pseudoprobe    6699318081062747564 1 0 @ 837061429793323041:6
.pseudoprobe    837061429793323041 4 0
popq    %rax
retq
```

**Disassembling**

We have a disassembling tool (llvm-profgen) that can display disassembly alongside with pseudo probes. So far it only supports ELF executable file.

An example disassembly looks like:

```
00000000002011a0 <foo2>:
  2011a0: 50                    push   rax
  2011a1: 85 ff                 test   edi,edi
  [Probe]:  FUNC: foo2  Index: 1  Type: Block
  2011a3: 74 02                 je     2011a7 <foo2+0x7>
  [Probe]:  FUNC: foo2  Index: 3  Type: Block
  [Probe]:  FUNC: foo2  Index: 4  Type: Block
  [Probe]:  FUNC: foo   Index: 1  Type: Block  Inlined: @ foo2:6
  2011a5: 58                    pop    rax
  2011a6: c3                    ret
  [Probe]:  FUNC: foo2  Index: 2  Type: Block
  2011a7: bf 01 00 00 00        mov    edi,0x1
  [Probe]:  FUNC: foo2  Index: 5  Type: IndirectCall
  2011ac: ff d6                 call   rsi
  [Probe]:  FUNC: foo2  Index: 4  Type: Block
  2011ae: 58                    pop    rax
  2011af: c3                    ret
```

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D91878
2020-12-10 17:29:28 -08:00
Mitch Phillips
7ead5f5aa3 Revert "[CSSPGO] Pseudo probe encoding and emission."
This reverts commit b035513c06d1cba2bae8f3e88798334e877523e1.

Reason: Broke the ASan buildbots:
  http://lab.llvm.org:8011/#/builders/5/builds/2269
2020-12-10 15:53:39 -08:00
Hongtao Yu
b035513c06 [CSSPGO] Pseudo probe encoding and emission.
This change implements pseudo probe encoding and emission for CSSPGO. Please see RFC here for more context: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s

Pseudo probes are in the form of intrinsic calls on IR/MIR but they do not turn into any machine instructions. Instead they are emitted into the binary as a piece of data in standalone sections.  The probe-specific sections are not needed to be loaded into memory at execution time, thus they do not incur a runtime overhead. 

**ELF object emission**

The binary data to emit are organized as two ELF sections, i.e, the `.pseudo_probe_desc` section and the `.pseudo_probe` section. The `.pseudo_probe_desc` section stores a function descriptor for each function and the `.pseudo_probe` section stores the actual probes, each fo which corresponds to an IR basic block or an IR function callsite. A function descriptor is stored as a module-level metadata during the compilation and is serialized into the object file during object emission.

Both the probe descriptors and pseudo probes can be emitted into a separate ELF section per function to leverage the linker for deduplication.  A `.pseudo_probe` section shares the same COMDAT group with the function code so that when the function is dead, the probes are dead and disposed too. On the contrary, a `.pseudo_probe_desc` section has its own COMDAT group. This is because even if a function is dead, its probes may be inlined into other functions and its descriptor is still needed by the profile generation tool.

The format of `.pseudo_probe_desc` section looks like:

```
.section   .pseudo_probe_desc,"",@progbits
.quad   6309742469962978389  // Func GUID
.quad   4294967295           // Func Hash
.byte   9                    // Length of func name
.ascii  "_Z5funcAi"          // Func name
.quad   7102633082150537521
.quad   138828622701
.byte   12
.ascii  "_Z8funcLeafi"
.quad   446061515086924981
.quad   4294967295
.byte   9
.ascii  "_Z5funcBi"
.quad   -2016976694713209516
.quad   72617220756
.byte   7
.ascii  "_Z3fibi"
```

For each `.pseudoprobe` section, the encoded binary data consists of a single function record corresponding to an outlined function (i.e, a function with a code entry in the `.text` section). A function record has the following format :

```
FUNCTION BODY (one for each outlined function present in the text section)
    GUID (uint64)
        GUID of the function
    NPROBES (ULEB128)
        Number of probes originating from this function.
    NUM_INLINED_FUNCTIONS (ULEB128)
        Number of callees inlined into this function, aka number of
        first-level inlinees
    PROBE RECORDS
        A list of NPROBES entries. Each entry contains:
          INDEX (ULEB128)
          TYPE (uint4)
            0 - block probe, 1 - indirect call, 2 - direct call
          ATTRIBUTE (uint3)
            reserved
          ADDRESS_TYPE (uint1)
            0 - code address, 1 - address delta
          CODE_ADDRESS (uint64 or ULEB128)
            code address or address delta, depending on ADDRESS_TYPE
    INLINED FUNCTION RECORDS
        A list of NUM_INLINED_FUNCTIONS entries describing each of the inlined
        callees.  Each record contains:
          INLINE SITE
            GUID of the inlinee (uint64)
            ID of the callsite probe (ULEB128)
          FUNCTION BODY
            A FUNCTION BODY entry describing the inlined function.
```

To support building a context-sensitive profile, probes from inlinees are grouped by their inline contexts. An inline context is logically a call path through which a callee function lands in a caller function. The probe emitter builds an inline tree based on the debug metadata for each outlined function in the form of a trie tree. A tree root is the outlined function. Each tree edge stands for a callsite where inlining happens. Pseudo probes originating from an inlinee function are stored in a tree node and the tree path starting from the root all the way down to the tree node is the inline context of the probes. The emission happens on the whole tree top-down recursively. Probes of a tree node will be emitted altogether with their direct parent edge. Since a pseudo probe corresponds to a real code address, for size savings, the address is encoded as a delta from the previous probe except for the first probe. Variant-sized integer encoding, aka LEB128, is used for address delta and probe index.

**Assembling**

Pseudo probes can be printed as assembly directives alternatively. This allows for good assembly code readability and also provides a view of how optimizations and pseudo probes affect each other, especially helpful for diff time assembly analysis.

A pseudo probe directive has the following operands in order: function GUID, probe index, probe type, probe attributes and inline context. The directive is generated by the compiler and can be parsed by the assembler to form an encoded `.pseudoprobe` section in the object file.

A example assembly looks like:

```
foo2: # @foo2
# %bb.0: # %bb0
pushq %rax
testl %edi, %edi
.pseudoprobe 837061429793323041 1 0 0
je .LBB1_1
# %bb.2: # %bb2
.pseudoprobe 837061429793323041 6 2 0
callq foo
.pseudoprobe 837061429793323041 3 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
.LBB1_1: # %bb1
.pseudoprobe 837061429793323041 5 1 0
callq *%rsi
.pseudoprobe 837061429793323041 2 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
# -- End function
.section .pseudo_probe_desc,"",@progbits
.quad 6699318081062747564
.quad 72617220756
.byte 3
.ascii "foo"
.quad 837061429793323041
.quad 281547593931412
.byte 4
.ascii "foo2"
```

With inlining turned on, the assembly may look different around %bb2 with an inlined probe:

```
# %bb.2:                                # %bb2
.pseudoprobe    837061429793323041 3 0
.pseudoprobe    6699318081062747564 1 0 @ 837061429793323041:6
.pseudoprobe    837061429793323041 4 0
popq    %rax
retq
```

**Disassembling**

We have a disassembling tool (llvm-profgen) that can display disassembly alongside with pseudo probes. So far it only supports ELF executable file.

An example disassembly looks like:

```
00000000002011a0 <foo2>:
  2011a0: 50                    push   rax
  2011a1: 85 ff                 test   edi,edi
  [Probe]:  FUNC: foo2  Index: 1  Type: Block
  2011a3: 74 02                 je     2011a7 <foo2+0x7>
  [Probe]:  FUNC: foo2  Index: 3  Type: Block
  [Probe]:  FUNC: foo2  Index: 4  Type: Block
  [Probe]:  FUNC: foo   Index: 1  Type: Block  Inlined: @ foo2:6
  2011a5: 58                    pop    rax
  2011a6: c3                    ret
  [Probe]:  FUNC: foo2  Index: 2  Type: Block
  2011a7: bf 01 00 00 00        mov    edi,0x1
  [Probe]:  FUNC: foo2  Index: 5  Type: IndirectCall
  2011ac: ff d6                 call   rsi
  [Probe]:  FUNC: foo2  Index: 4  Type: Block
  2011ae: 58                    pop    rax
  2011af: c3                    ret
```

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D91878
2020-12-10 09:50:08 -08:00
Jian Cai
c6334db577 [X86] support .nops directive
Add support of .nops on X86. This addresses llvm.org/PR45788.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D82826
2020-08-03 11:50:56 -07:00
Thomas Preud'homme
6c67ee0f58 [MC] Fix PR45805: infinite recursion in assembler
Give up folding an expression if the fragment of one of the operands
would require laying out a fragment already being laid out. This
prevents hitting an infinite recursion when a fill size expression
refers to a later fragment since computing the offset of that fragment
would require laying out the fill fragment and thus computing its size
expression.

Reviewed By: echristo

Differential Revision: https://reviews.llvm.org/D79570
2020-06-25 15:42:36 +01:00
Philip Reames
b4c8608eba Adjust debug output for MCRelaxableFragment to include the size so that sanity checking relaxation offsets from -debug output is easier 2020-03-13 16:22:46 -07:00
Shengchen Kan
3a503ce663 [X86] Reduce the number of emitted fragments due to branch align
Summary:
Currently, a BoundaryAlign fragment may be inserted after the branch
that needs to be aligned to truncate the current fragment, this fragment is
unused at most of time. To avoid that, we can insert a new empty Data
fragment instead. Non-relaxable instruction is usually emitted into Data
fragment, so the inserted empty Data fragment will be reused at a high
possibility.

Reviewers: annita.zhang, reames, MaskRay, craig.topper, LuoYuanke, jyknight

Reviewed By: reames, LuoYuanke

Subscribers: llvm-commits, dexonsmith, hiraditya

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75438
2020-03-12 15:37:35 +08:00
Shengchen Kan
af57b139a0 Temporarily Revert [X86] Not track size of the boudaryalign fragment during the layout
Summary: This reverts commit 2ac19feb1571960b8e1479a451b45ab56da7034e.
This commit causes some test cases to run fail when branch is aligned.
2020-03-03 11:15:56 +08:00
Shengchen Kan
2ac19feb15 [X86] Not track size of the boudaryalign fragment during the layout
Summary:
Currently the boundaryalign fragment caches its size during the process
of layout and then it is relaxed and update the size in each iteration. This
behaviour is unnecessary and ugly.

Reviewers: annita.zhang, reames, MaskRay, craig.topper, LuoYuanke, jyknight

Reviewed By: MaskRay

Subscribers: hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75404
2020-03-02 09:32:30 +08:00
Fangrui Song
806a2b1f3d [MC] Reorder MCFragment members to decrease padding
sizeof(MCFragment) does not change, but some if its subclasses do, e.g.
on a 64-bit platform,
sizeof(MCEncodedFragment) decreases from 64 to 56,
sizeof(MCDataFragment) decreases from 224 to 216.
2020-01-05 19:09:40 -08:00
Fangrui Song
2c053109fa [MC] Delete MCFragment::isDummy. NFC
isa<...>, dyn_cast<...> and cast<...> are used by other fragments.
Don't make MCDummyFragment special.
2020-01-05 18:49:47 -08:00
Shengchen Kan
70fa4c4f88 [NFC] Style cleanups
1. Remove duplicate function for class name at the beginning of the
comment.
2. Use auto where the type is already obvious from the context.
2019-12-23 17:02:36 +08:00
Philip Reames
14fc20ca62 Align branches within 32-Byte boundary (NOP padding)
WARNING: If you're looking at this patch because you're looking for a full
performace mitigation of the Intel JCC Erratum, this is not it!

This is a preliminary patch on the patch towards mitigating the performance
regressions caused by Intel's microcode update for Jump Conditional Code
Erratum.  For context, see:
https://www.intel.com/content/www/us/en/support/articles/000055650.html

The patch adds the required assembler infrastructure and command line options
needed to exercise the logic for INTERNAL TESTING.  These are NOT public flags,
and should not be used for anything other than LLVM's own testing/debugging
purposes.  They are likely to change both in spelling and meaning.

WARNING: This patch is knowingly incorrect in some cornercases.  We need, and
do not yet provide, a mechanism to selective enable/disable the padding.
Conversation on this will continue in parellel with work on extending this
infrastructure to support prefix padding.

The goal here is to have the assembler align specific instructions such that
they neither cross or end at a 32 byte boundary.  The impacted instructions are:
a. Conditional jump.
b. Fused conditional jump.
c. Unconditional jump.
d. Indirect jump.
e. Ret.
f. Call.

The new options for llvm-mc are:
    -x86-align-branch-boundary=NUM aligns branches within NUM byte boundary.
    -x86-align-branch=TYPE[+TYPE...] specifies types of branches to align.

A new MCFragment type, MCBoundaryAlignFragment, is added, which may emit
NOP to align the fused/unfused branch.

alignBranchesBegin inserts MCBoundaryAlignFragment before instructions,
alignBranchesEnd marks the end of the branch to be aligned,
relaxBoundaryAlign grows or shrinks sizes of NOP to align the target branch.

Nop padding is disabled when the instruction may be rewritten by the linker,
such as TLS Call.

Process Note: I am landing a patch by skan as it has been LGTMed, and
continuing to iterate on the review is simply slowing us down at this point.
We can and will continue to iterate in tree.

Patch By: skan
Differential Revision: https://reviews.llvm.org/D70157
2019-12-20 11:35:50 -08:00
Fangrui Song
9574757dba [MC] Delete MCCodePadder
D34393 added MCCodePadder as an infrastructure for padding code with
NOP instructions. It lacked tests and was not being worked on since
then.

Intel has now worked on an assembler patch to mitigate performance loss
after applying microcode update for the Jump Conditional Code Erratum.

https://www.intel.com/content/www/us/en/support/articles/000055650/processors.html

This new patch shares similarity with MCCodePadder, but has a concrete
use case in mind and is being actively developed. The infrastructure it
introduces can potentially be used for general performance improvement
via alignment. Delete the unused MCCodePadder so that people can develop
the new feature from a clean state.

Reviewed By: jyknight, skan

Differential Revision: https://reviews.llvm.org/D71106
2019-12-09 19:21:31 -08:00
Fangrui Song
2d0eb38d4c [MC] Make MCFragment trivially destructible 2019-11-11 18:11:15 -08:00
Chandler Carruth
2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
George Rimar
a3d0d5fe68 [MC] - Fix build bot.
Error was:
/home/buildslave/slave_as-bldslv8/lld-perf-testsuite/llvm/lib/MC/MCFragment.cpp:241:22: error: field 'Offset' will be initialized after field 'LayoutOrder' [-Werror,-Wreorder]
      Atom(nullptr), Offset(~UINT64_C(0)), LayoutOrder(0) {

http://lab.llvm.org:8011/builders/lld-perf-testsuite/builds/9628/steps/build-bin%2Flld/logs/stdio

llvm-svn: 348351
2018-12-05 11:06:29 +00:00
George Rimar
79ace92fcd Recommit r348243 - "[llvm-mc] - Do not crash when referencing undefined debug sections."
The patch triggered an unrelated msan issue: LayoutOrder variable was not initialized.
(http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/26794/steps/check-llvm%20msan/logs/stdio)
It was fixed.

Original commit message:
MC has code that pre-creates few debug sections:
https://github.com/llvm-mirror/llvm/blob/master/lib/MC/MCObjectFileInfo.cpp#L396

If users code has a reference to such section but does not redefine it,
MC code currently asserts, because still thinks they are normally defined.

The patch fixes the issue.

Differential revision: https://reviews.llvm.org/D55173
----
Modified : /llvm/trunk/lib/MC/ELFObjectWriter.cpp
Added : /llvm/trunk/test/MC/ELF/undefined-debug.s

llvm-svn: 348349
2018-12-05 10:43:58 +00:00
Nirav Dave
b35f9e1459 Fix typoed cast to avoid assertion in MCFragment::dump.
llvm-svn: 334959
2018-06-18 16:26:11 +00:00
Peter Smith
1503fc0fd0 [MC] Move bundling and MCSubtargetInfo to MCEncodedFragment [NFC]
Instruction bundling is only supported on descendants of the
MCEncodedFragment type. By moving the bundling functionality and
MCSubtargetInfo to this class it makes it easier to set and extract the
MCSubtargetInfo when it is necessary.

This is a refactoring change that will make it easier to pass the
MCSubtargetInfo through to writeNops when nop padding is required.

Differential Revision: https://reviews.llvm.org/D45959

llvm-svn: 334814
2018-06-15 09:48:18 +00:00
Sam Clegg
8c32e913b5 [MC] Move MCAssembler::dump into the correct cpp file. NFC
Differential Revision: https://reviews.llvm.org/D46556

llvm-svn: 334713
2018-06-14 14:04:23 +00:00
Nirav Dave
588fad4d3b [MC] Relax .fill size requirements
Avoid requirement that number of values must be known at assembler
time.

Fixes PR33586.

Reviewers: rnk, peter.smith, echristo, jyknight

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D46703

llvm-svn: 332741
2018-05-18 17:45:48 +00:00
Nico Weber
432a38838d IWYU for llvm-config.h in llvm, additions.
See r331124 for how I made a list of files missing the include.
I then ran this Python script:

    for f in open('filelist.txt'):
        f = f.strip()
        fl = open(f).readlines()

        found = False
        for i in xrange(len(fl)):
            p = '#include "llvm/'
            if not fl[i].startswith(p):
                continue
            if fl[i][len(p):] > 'Config':
                fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
                found = True
                break
        if not found:
            print 'not found', f
        else:
            open(f, 'w').write(''.join(fl))

and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.

No intended behavior change.

llvm-svn: 331184
2018-04-30 14:59:11 +00:00
Adrian McCarthy
75248a7ade NFC: Rename MCSafeSEHFragment to MCSymbolIdFragment
Summary:
This fragment emits a symbol ID and will be useful for more than just Safe SEH
tables (e.g., I plan to re-use it for Control Flow Guard tables).  This is
simply a rename refactor.

Reviewers: rnk

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D39770

llvm-svn: 317703
2017-11-08 18:57:02 +00:00
Omer Paparo Bivas
2251c79aba [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
llvm-svn: 316413
2017-10-24 06:16:03 +00:00
Aaron Ballman
615eb47035 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

llvm-svn: 315854
2017-10-15 14:32:27 +00:00
Don Hinton
3e0199f7eb [dump] Remove NDEBUG from test to enable dump methods [NFC]
Summary:
Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with
LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP.

Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods.

Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so
it'll be picked up by public headers.

Differential Revision: https://reviews.llvm.org/D38406

llvm-svn: 315590
2017-10-12 16:16:06 +00:00
Mandeep Singh Grang
1be19e6f5b [llvm] Fix some typos. NFC.
Reviewers: mcrosier

Reviewed By: mcrosier

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D37922

llvm-svn: 313388
2017-09-15 20:01:43 +00:00
Ekaterina Vaartis
c4a6322153 [MC] Fix const qualifier warning
llvm-svn: 306045
2017-06-22 19:08:30 +00:00
Sam Clegg
58ad080ef0 MC: Fix dumping of MCFragment values
Without this cast the "char" overload of operator<< is
chosen and the values is output as an ascii rather than
an integer.

Differential Revision: https://reviews.llvm.org/D34486

llvm-svn: 306039
2017-06-22 17:57:01 +00:00
Sam Clegg
705f798bff Mark dump() methods as const. NFC
Add const qualifier to any dump() method where adding one
was trivial.

Differential Revision: https://reviews.llvm.org/D34481

llvm-svn: 305963
2017-06-21 22:19:17 +00:00
Chandler Carruth
6bda14b313 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Eugene Zelenko
1d43552a40 [MC] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 294369
2017-02-07 23:02:00 +00:00
Matthias Braun
8c209aa877 Cleanup dump() functions.
We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html

For reference:
- Public headers should just declare the dump() method but not use
  LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
  #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  LLVM_DUMP_METHOD void MyClass::dump() {
    // print stuff to dbgs()...
  }
  #endif

llvm-svn: 293359
2017-01-28 02:02:38 +00:00
Chad Rosier
9245e12f95 [Assembler] Improve error when unable to evaluate expression.
Add a SMLoc to MCExpr. Most code does not generate or consume the SMLoc (yet).

Patch by Sanne Wouda <sanne.wouda@arm.com>!
Differential Revision: https://reviews.llvm.org/D28861

llvm-svn: 292515
2017-01-19 20:06:32 +00:00
Duncan P. N. Exon Smith
f947c3afe1 ADT: Split ilist_node_traits into alloc and callback, NFC
Many lists want to override only allocation semantics, or callbacks for
iplist.  Split these up to prevent code duplication.
- Specialize ilist_alloc_traits to change the implementations of
  deleteNode() and createNode().
- One common desire is to do nothing deleteNode() and disable
  createNode().  Specialize ilist_alloc_traits to inherit from
  ilist_noalloc_traits for that behaviour.
- Specialize ilist_callback_traits to use the addNodeToList(),
  removeNodeFromList(), and transferNodesFromList() callbacks.

As a drive-by, add some coverage to the callback-related unit tests.

llvm-svn: 280128
2016-08-30 18:40:47 +00:00
Reid Kleckner
a5b1eef846 [MC] Move .cv_loc management logic out of MCContext
MCContext already has many tasks, and separating CodeView out from it is
probably a good idea. The .cv_loc tracking was modelled on the DWARF
tracking which lived directly in MCContext.

Removes the inclusion of MCCodeView.h from MCContext.h, so now there are
only 10 build actions while I hack on CodeView support instead of 265.

llvm-svn: 279847
2016-08-26 17:58:37 +00:00
Duncan P. N. Exon Smith
b29ec1e040 ADT: Remove ilist_*sentinel_traits, NFC
Remove all the dead code around ilist_*sentinel_traits.  This is a
follow-up to gutting them as part of r279314 (originally r278974),
staged to prevent broken builds in sub-projects.

Uses were removed from clang in r279457 and lld in r279458.

llvm-svn: 279473
2016-08-22 20:51:00 +00:00
Davide Italiano
80d379f228 [MC] Remove guard(s). NFCI.
All the methods are already marked with
LLVM_DUMP_METHOD.

llvm-svn: 279428
2016-08-22 11:55:22 +00:00
Mehdi Amini
b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
David Majnemer
408b5e6603 [MC] Add support for encoding CodeView variable definition ranges
CodeView, like most other debug formats, represents the live range of a
variable so that debuggers might print them out.

They use a variety of records to represent how a particular variable
might be available (in a register, in a frame pointer, etc.) along with
a set of ranges where this debug information is relevant.

However, the format only allows us to use ranges which are limited to a
maximum of 0xF000 in size.  This means that we need to split our debug
information into chunks of 0xF000.

Because the layout of code is not known until *very* late, we must use a
new fragment to record the information we need until we can know
*exactly* what the range is.

llvm-svn: 259868
2016-02-05 01:55:49 +00:00
Reid Kleckner
1fcd610c94 [codeview] Wire up the .cv_inline_linetable directive
This directive emits the binary annotations that describe line and code
deltas in inlined call sites. Single-stepping through inlined frames in
windbg now works.

llvm-svn: 259535
2016-02-02 17:41:18 +00:00
Yaron Keren
eb2a25467e Annotate dump() methods with LLVM_DUMP_METHOD, addressing Richard Smith r259192 post commit comment.
clang part in r259232, this is the LLVM part of the patch.

llvm-svn: 259240
2016-01-29 20:50:44 +00:00
Rafael Espindola
1a7e8b4bc1 Simplify MCFillFragment.
The value size was always 1 or 0, so we don't need to store it.

In a no asserts build this takes the testcase of pr26208 from 11 to 10
seconds.

llvm-svn: 258141
2016-01-19 16:57:08 +00:00