Commit Graph

686 Commits

Author SHA1 Message Date
Teresa Johnson 7bea1aad6a [ThinLTO] Compute GUID directly from GV when building per-module index
Summary:
I discovered when writing the summary parsing support that the
per-module index builder and writer are computing the GUID from the
value name alone (ignoring the linkage type). This was ok since those
GUID were not emitted in the bitcode, and there are never multiple
conflicting names in a single module.

However, I don't see a reason for making the GUID computation different
for the per-module case. It also makes things simpler on the parsing
side to have the GUID computation consistent. So this patch changes the
summary analysis phase and the per-module summary writer to compute the
GUID using the facility on the GlobalValue.

Reviewers: pcc, dexonsmith

Subscribers: llvm-commits, inglorion

Differential Revision: https://reviews.llvm.org/D47844

llvm-svn: 335560
2018-06-26 00:20:49 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +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
Mandeep Singh Grang 176c3efa0e [Bitcode] Change std::sort to llvm::sort in response to r327219
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: pcc, mehdi_amini, dexonsmith

Reviewed By: dexonsmith

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45132

llvm-svn: 329334
2018-04-05 19:27:04 +00:00
Vlad Tsyrklevich d17f61ea3b Add the ShadowCallStack attribute
Summary:
Introduce the ShadowCallStack function attribute. It's added to
functions compiled with -fsanitize=shadow-call-stack in order to mark
functions to be instrumented by a ShadowCallStack pass to be submitted
in a separate change.

Reviewers: pcc, kcc, kubamracek

Reviewed By: pcc, kcc

Subscribers: cryptoad, mehdi_amini, javed.absar, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D44800

llvm-svn: 329108
2018-04-03 20:10:40 +00:00
Teresa Johnson db83aceb06 [ThinLTO] Add an option to force summary call edges cold for debugging
Summary:
Useful to selectively disable importing into specific modules for
debugging/triaging/workarounds.

Reviewers: eraman

Subscribers: inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D45062

llvm-svn: 328909
2018-03-31 00:18:08 +00:00
Matt Morehouse 236cdaf84c [SimplifyCFG] Create attribute for fuzzing-specific optimizations.
Summary:
When building with libFuzzer, converting control flow to selects or
obscuring the original operands of CMPs reduces the effectiveness of
libFuzzer's heuristics.

This patch provides an attribute to disable or modify certain optimizations
for optimal fuzzing signal.

Provides a less aggressive alternative to https://reviews.llvm.org/D44057.

Reviewers: vitalybuka, davide, arsenm, hfinkel

Reviewed By: vitalybuka

Subscribers: junbuml, mehdi_amini, wdng, javed.absar, hiraditya, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D44232

llvm-svn: 328214
2018-03-22 17:07:51 +00:00
Oren Ben Simhon fdd72fd522 [X86] Added support for nocf_check attribute for indirect Branch Tracking
X86 Supports Indirect Branch Tracking (IBT) as part of Control-Flow Enforcement Technology (CET).
IBT instruments ENDBR instructions used to specify valid targets of indirect call / jmp.
TheĀ `nocf_check` attribute has two roles in the context of X86 IBT technology:
	1. Appertains to a function - do not add ENDBR instruction at the beginning of the function.
	2. Appertains to a function pointer - do not track the target function of this pointer by adding nocf_check prefix to the indirect-call instruction.

This patch implementsĀ `nocf_check` context for Indirect Branch Tracking.
It also auto generatesĀ `nocf_check` prefixes before indirect branchs to jump tables that are guarded by range checks.

Differential Revision: https://reviews.llvm.org/D41879

llvm-svn: 327767
2018-03-17 13:29:46 +00:00
Scott Linder 16c7bdaf32 [DebugInfo] Support DWARF v5 source code embedding extension
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.

Add new optional attribute for !DIFile IR metadata called source which contains
source text. Use this to output the source to the DWARF line table of code
objects. Analogously extend METADATA_FILE in Bitcode and .file directive in ASM
to support optional source.

Teach llvm-dwarfdump and llvm-objdump about the new values. Update the output
format of llvm-dwarfdump to make room for the new attribute on file_names
entries, and support embedded sources for the -source option in llvm-objdump.

Differential Revision: https://reviews.llvm.org/D42765

llvm-svn: 325970
2018-02-23 23:01:06 +00:00
Steven Wu 545d34a272 bitcode support change for fast flags compatibility
Summary: The discussion and as per need, each vendor needs a way to keep the old fast flags and the new fast flags in the auto upgrade path of the IR upgrader.  This revision addresses that issue.

Patched by Michael Berg

Reviewers: qcolombet, hans, steven_wu

Reviewed By: qcolombet, steven_wu

Subscribers: dexonsmith, vsk, mehdi_amini, andrewrk, MatzeB, wristow, spatel

Differential Revision: https://reviews.llvm.org/D43253

llvm-svn: 325525
2018-02-19 19:22:28 +00:00
Vitaly Buka 769134dac3 [ThinLTO] Allow indexing to request backend to ignore the module
Summary:
Gold plugin does not add pass to ThinLTO modules without useful symbols.
In this case ThinLTO can't create corresponding index file and some features, like CFI,
cannot be processes by backed correctly without index.
Given that we don't need the backed output we can request it to avoid
processing the module. This is implemented by this patch using new
"SkipModuleByDistributedBackend" flag.

Reviewers: pcc, tejohnson

Subscribers: mehdi_amini, inglorion, eraman, cfe-commits

Differential Revision: https://reviews.llvm.org/D42995

llvm-svn: 325411
2018-02-16 23:38:22 +00:00
Vitaly Buka 44396faabc [ThinLTO/CFI] Include TYPE_ID summaries into GLOBALVAL_SUMMARY_BLOCK
Summary:
TypeID summaries are used by CFI and need to be serialized by ThinLTO
indexing for later use by LTO Backend.

Reviewers: tejohnson, pcc

Subscribers: mehdi_amini, inglorion, eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D42611

llvm-svn: 325182
2018-02-14 22:41:15 +00:00
Rafael Espindola 6a86e25d90 Pass a reference to a module to the bitcode writer.
This simplifies most callers as they are already using references or
std::unique_ptr.

llvm-svn: 325155
2018-02-14 19:11:32 +00:00
Scott Linder 7160384d40 [DebugInfo] Unify ChecksumKind and Checksum value in DIFile
Rather than encode the absence of a checksum with a Kind variant, instead put
both the kind and value in a struct and wrap it in an Optional.

Differential Revision: http://reviews.llvm.org/D43043

llvm-svn: 324928
2018-02-12 19:45:54 +00:00
Momchil Velikov 08dc66eff0 Re-commit r324489: [DebugInfo] Improvements to representation of enumeration types (PR36168)
Differential Revision: https://reviews.llvm.org/D42734

llvm-svn: 324899
2018-02-12 16:10:09 +00:00
Momchil Velikov 74906a467c Revert "[DebugInfo] Improvements to representation of enumeration types (PR36168)"
Revert commit r324489, it broke LLDB tests.

llvm-svn: 324511
2018-02-07 20:28:47 +00:00
Momchil Velikov c502027efd [DebugInfo] Improvements to representation of enumeration types (PR36168)
This patch is the LLVM part of fixing the issues, described in
https://bugs.llvm.org/show_bug.cgi?id=36168

* The representation of enumerator values in the debug info metadata now
  contains a boolean flag isUnsigned, which determines how the bits of
  the value are interpreted.
* The DW_TAG_enumeration type DIE now always (for DWARF version >= 3)
  includes a DW_AT_type attribute, which refers to the underlying
  integer type, as suggested in DWARFv4 (5.7 Enumeration Type Entries).
* The debug info metadata for enumeration type contains (in flags)
  indication whether this is a C++11 "fixed enum".
* For C++11 enumeration with a fixed underlying type, the DIE also
  includes the DW_AT_enum_class attribute (for DWARF version >= 4).
* Encoding of enumerator constants uses DW_FORM_sdata for signed values
  and DW_FORM_udata for unsigned values, as suggested by DWARFv4 (7.5.4
  Attribute Encodings).

The changes should be backwards compatible:

* the isUnsigned attribute is optional and defaults to false.
* if the underlying type for the enumeration is not available, the
  enumerator values are considered signed.
* the FixedEnum flag defaults to clear.
* the bitcode format for DIEnumerator stores the unsigned flag bit #1 of
  the first record element, so the format does not change and the zero
  previously stored there is consistent with the false default for
  IsUnsigned.

Differential Revision: https://reviews.llvm.org/D42734

llvm-svn: 324489
2018-02-07 16:46:33 +00:00
Teresa Johnson f368101567 [ThinLTO] Serialize WithGlobalValueDeadStripping index flag for distributed backends
Summary:
A recent fix to drop dead symbols (r323633) did not work for ThinLTO
distributed backends because we lose the WithGlobalValueDeadStripping
set on the index during the thin link. This patch adds a new flags
record to the bitcode format for the index, and serializes this flag
for the combined index (it would always be 0 for the per-module index
generated by the compile step, so no need to serialize the new flags
record there until/unless we add another flag that applies to the
per-module indexes).

Generally this flag should always be set for the distributed backends,
which are necessarily performed after the thin link. However, if we were
to simply set this flag on the index applied to the distributed backends
(invoked via clang), we would lose the ability to disable dead stripping
via -compute-dead=false for debugging purposes.

Reviewers: grimar, pcc

Subscribers: mehdi_amini, inglorion, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D42799

llvm-svn: 324444
2018-02-07 04:05:59 +00:00
Adrian Prantl 8c59921ca3 Add DWARF for discriminated unions
n Rust, an enum that carries data in the variants is, essentially, a
discriminated union. Furthermore, the Rust compiler will perform
space optimizations on such enums in some situations. Previously,
DWARF for these constructs was emitted using a hack (a magic field
name); but this approach stopped working when more space optimizations
were added in https://github.com/rust-lang/rust/pull/45225.

This patch changes LLVM to allow discriminated unions to be
represented in DWARF. It adds createDiscriminatedUnionType and
createDiscriminatedMemberType to DIBuilder and then arranges for this
to be emitted using DWARF's DW_TAG_variant_part and DW_TAG_variant.

Note that DWARF requires that a discriminated union be represented as
a structure with a variant part. However, as Rust only needs to emit
pure discriminated unions, this is what I chose to expose on
DIBuilder.

Patch by Tom Tromey!

Differential Revision: https://reviews.llvm.org/D42082

llvm-svn: 324426
2018-02-06 23:45:59 +00:00
Easwaran Raman c73cec84c9 Re-land "[ThinLTO] Add call edges' relative block frequency to per-module summary."
It was reverted after buildbot regressions.

Original commit message:

This allows relative block frequency of call edges to be passed
to the thinlink stage where it will be used to compute synthetic
entry counts of functions.

llvm-svn: 323460
2018-01-25 19:27:17 +00:00
Easwaran Raman bf38deef3f Revert "[ThinLTO] Add call edges' relative block frequency to per-module summary."
Causes buildbot regressions.

llvm-svn: 323358
2018-01-24 18:15:29 +00:00
Easwaran Raman 5f7aff9a0a [ThinLTO] Add call edges' relative block frequency to per-module summary.
Summary:
This allows relative block frequency of call edges to be passed to the
thinlink stage where it will be used to compute synthetic entry counts
of functions.

Reviewers: tejohnson, pcc

Subscribers: mehdi_amini, llvm-commits, inglorion

Differential Revision: https://reviews.llvm.org/D42212

llvm-svn: 323349
2018-01-24 17:51:23 +00:00
Sander de Smalen fdf40917d9 [Metadata] Extend 'count' field of DISubrange to take a metadata node
Summary:
This patch extends the DISubrange 'count' field to take either a
(signed) constant integer value or a reference to a DILocalVariable
or DIGlobalVariable.

This is patch [1/3] in a series to extend LLVM's DISubrange Metadata
node to support debugging of C99 variable length arrays and vectors with
runtime length like the Scalable Vector Extension for AArch64. It is
also a first step towards representing more complex cases like arrays
in Fortran.

Reviewers: echristo, pcc, aprantl, dexonsmith, clayborg, kristof.beyls, dblaikie

Reviewed By: aprantl

Subscribers: rnk, probinson, fhahn, aemerson, rengolin, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D41695

llvm-svn: 323313
2018-01-24 09:56:07 +00:00
Rafael Espindola 3b9843f0ff Allow dso_local on ifunc.
It was never fully disallowed. We were rejecting it in the asm parser,
but not in the verifier.

Currently TargetMachine::shouldAssumeDSOLocal returns true for hidden
ifuncs. I considered changing it and moving the check from the asm
parser to the verifier.

The reason for deciding to allow it instead is that all linkers handle
a direct reference just fine. They use the plt address as the address
of the function. In fact doing that means that clang doesn't have the
same bug as gcc: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83782.

This patch then removes the check from the asm parser and updates the
bitcode reader and writer.

llvm-svn: 322378
2018-01-12 17:03:43 +00:00
Easwaran Raman a17f220590 Add hasProfileData() to check if a function has profile data. NFC.
Summary:
This replaces calls to getEntryCount().hasValue() with hasProfileData
that does the same thing. This refactoring is useful to do before adding
synthetic function entry counts but also a useful cleanup IMO even
otherwise. I have used hasProfileData instead of hasRealProfileData as
David had earlier suggested since I think profile implies "real" and I
use the phrase "synthetic entry count" and not "synthetic profile count"
but I am fine calling it hasRealProfileData if you prefer.

Reviewers: davidxl, silvas

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41461

llvm-svn: 321331
2017-12-22 01:33:52 +00:00