Commit Graph

218 Commits

Author SHA1 Message Date
Jonas Devlieghere e13e6dbe40 [MC] Add interface to finish pending labels.
When manually finishing the object writer in dsymutil, it's possible
that there are pending labels that haven't been resolved. This results
in an assertion when the assembler tries to fixup a label that doesn't
have an address yet.

Differential revision: https://reviews.llvm.org/D49131

llvm-svn: 336688
2018-07-10 15:32:17 +00:00
Paul Robinson c17c8bf749 Support -fdebug-prefix-map in llvm-mc. This is useful to omit the
debug compilation dir when compiling assembly files with -g.
Part of PR38050.

Patch by Siddhartha Bagaria!

Differential Revision: https://reviews.llvm.org/D48988

llvm-svn: 336680
2018-07-10 14:41:54 +00:00
Sam Clegg c0dba0af01 Revert "[MC] Factor MCObjectStreamer::addFragmentAtoms out of MachO streamer."
This reverts rL331412.  We didn't up using fragment atoms
in the wasm object writer after all.

Differential Revision: https://reviews.llvm.org/D48173

llvm-svn: 334734
2018-06-14 17:11:19 +00:00
Peter Smith 57f661bd7d [MC] Pass MCSubtargetInfo to fixupNeedsRelaxation and applyFixup
On targets like Arm some relaxations may only be performed when certain
architectural features are available. As functions can be compiled with
differing levels of architectural support we must make a judgement on
whether we can relax based on the MCSubtargetInfo for the function. This
change passes through the MCSubtargetInfo for the function to
fixupNeedsRelaxation so that the decision on whether to relax can be made
per function. In this patch, only the ARM backend makes use of this
information. We must also pass the MCSubtargetInfo to applyFixup because
some fixups skip error checking on the assumption that relaxation has
occurred, to prevent code-generation errors applyFixup must see the same
MCSubtargetInfo as fixupNeedsRelaxation.

Differential Revision: https://reviews.llvm.org/D44928

llvm-svn: 334078
2018-06-06 09:40:06 +00:00
Peter Collingbourne f7b81db715 MC: Change the streamer ctors to take an object writer instead of a stream. NFCI.
The idea is that a client that wants split dwarf would create a
specific kind of object writer that creates two files, and use it to
create the streamer.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47050

llvm-svn: 332749
2018-05-18 18:26:45 +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
Sam Clegg 87cc4dbde7 [MC] Factor MCObjectStreamer::addFragmentAtoms out of MachO streamer.
This code previously existed only in MCMachOStreamer but is
useful for WebAssembly too.  See: D46335

Differential Revision: https://reviews.llvm.org/D46297

llvm-svn: 331412
2018-05-02 23:01:10 +00:00
Nirav Dave 6c0665e221 [MC] Change AsmParser to leverage Assembler during evaluation
Teach AsmParser to check with Assembler for when evaluating constant
expressions.  This improves the handing of preprocessor expressions
that must be resolved at parse time. This idiom can be found as
assembling-time assertion checks in source-level assemblers. Note that
this relies on the MCStreamer to keep sufficient tabs on Section /
Fragment information which the MCAsmStreamer does not. As a result the
textual output may fail where the equivalent object generation would
pass. This can most easily be resolved by folding the MCAsmStreamer
and MCObjectStreamer together which is planned for in a separate
patch.

Currently, this feature is only enabled for assembly input, keeping IR
compilation consistent between assembly and object generation.

Reviewers: echristo, rnk, probinson, espindola, peter.smith

Reviewed By: peter.smith

Subscribers: eraman, peter.smith, arichardson, jyknight, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45164

llvm-svn: 331218
2018-04-30 19:22:40 +00:00
Nirav Dave 6b01b88012 [MC] Undo spurious commit added into r331052.
llvm-svn: 331055
2018-04-27 16:16:06 +00:00
Nirav Dave 38b4b54a2c [MC] Provide default value for IsResolved.
llvm-svn: 331052
2018-04-27 16:11:24 +00:00
Nirav Dave 8728e097df [MC] Allow MCAssembler to be constructed without all subcomponents. NFCI.
llvm-svn: 331047
2018-04-27 15:45:27 +00:00
Reid Kleckner 2c6430fe3c [codeview] Ignore .cv_loc directives at the end of a function
If no data or instructions are emitted after a location directive, we
should clear the cv_loc when we change sections, or it will be emitted
at the beginning of the next section. This violates our invariant that
all .cv_loc directives belong to the same section. Add clearer
assertions for this.

llvm-svn: 330884
2018-04-25 23:34:15 +00:00
Reid Kleckner 5a791ee408 Re-land r327620 "[CodeView] Initial support for emitting S_BLOCK32 symbols for lexical scopes"
This is safe to land now that we don't copy FunctionInfo when rehashing
the DenseMap.

llvm-svn: 327670
2018-03-15 21:24:04 +00:00
Rafael Espindola d09b416943 Use assembler expressions to lay out the EH LSDA.
Rely on the assembler to finalize the layout of the DWARF/Itanium
exception-handling LSDA. Rather than calculate the exact size of each
thing in the LSDA, use assembler directives:

    To emit the offset to the TTBase label:

.uleb128 .Lttbase0-.Lttbaseref0
.Lttbaseref0:

    To emit the size of the call site table:

.uleb128 .Lcst_end0-.Lcst_begin0
.Lcst_begin0:
... call site table entries ...
.Lcst_end0:

    To align the type info table:

... action table ...
.balign 4
.long _ZTIi
.long _ZTIl
.Lttbase0:

Using assembler directives simplifies the compiler and allows switching
the encoding of offsets in the call site table from udata4 to uleb128 for
a large code size savings. (This commit does not change the encoding.)

The combination of the uleb128 followed by a balign creates an unfortunate
dependency cycle that the assembler must sometimes resolve either by
padding an LEB or by inserting zero padding before the type table. See
PR35809 or GNU as bug 4029.

Patch by Ryan Prichard!

llvm-svn: 324749
2018-02-09 17:00:25 +00:00
Rafael Espindola d707c37072 Use a MCExpr for the size of MCFillFragment.
This allows the size to be found during ralaxation. This fixes
pr35858.

llvm-svn: 322131
2018-01-09 22:48:37 +00:00
Rafael Espindola e70ececad0 Inline a emitFill variant that is only used once. NFC.
llvm-svn: 322111
2018-01-09 19:50:29 +00:00
Rafael Espindola 8fcd07d53c Make one of the emitFill methods non virtual. NFC.
This is just preparatory work to fix PR35858.

llvm-svn: 322108
2018-01-09 19:29:33 +00:00
Michael Zolotukhin 910c0129c8 Remove redundant includes from lib/MC.
llvm-svn: 320624
2017-12-13 21:30:54 +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
Lang Hames 2241ffa43c [MC] Have MCObjectStreamer take its MCAsmBackend argument via unique_ptr.
MCObjectStreamer owns its MCCodeEmitter -- this fixes the types to reflect that,
and allows us to remove the last instance of MCObjectStreamer's weird "holding
ownership via someone else's reference" trick.

llvm-svn: 315531
2017-10-11 23:34:47 +00:00
Lang Hames 02d330548d [MC] Have MCObjectStreamer take its MCAsmBackend argument via unique_ptr.
MCObjectStreamer owns its MCAsmBackend -- this fixes the types to reflect that,
and allows us to remove another instance of MCObjectStreamer's weird "holding
ownership via someone else's reference" trick.

llvm-svn: 315410
2017-10-11 01:57:21 +00:00
Lang Hames 60fbc7cc38 [MC] Thread unique_ptr<MCObjectWriter> through the create.*ObjectWriter
functions.

This makes the ownership of the resulting MCObjectWriter clear, and allows us
to remove one instance of MCObjectStreamer's bizarre "holding ownership via
someone else's reference" trick.

llvm-svn: 315327
2017-10-10 16:28:07 +00:00
Reid Kleckner ab23dace56 [MC] Suppress .Lcfi labels when emitting textual assembly
Summary:
This suppresses the generation of .Lcfi labels in our textual assembler.
It was annoying that this generated cascading .Lcfi labels:
  llc foo.ll -o - | llvm-mc | llvm-mc

After three trips through MCAsmStreamer, we'd have three labels in the
output when none are necessary. We should only bother creating the
labels and frame data when making a real object file.

This supercedes D38605, which moved the entire .seh_ implementation into
MCObjectStreamer.

This has the advantage that we do more checking when emitting textual
assembly, as a minor efficiency cost. Outputting textual assembly is not
performance critical, so this shouldn't matter.

Reviewers: majnemer, MatzeB

Subscribers: qcolombet, nemanjai, javed.absar, eraman, hiraditya, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D38638

llvm-svn: 315259
2017-10-10 00:57:36 +00:00
Lang Hames 0b9db4c1fa [MC] Use a unique_ptr<MCAssembler> for MCObjectStreamer's Assembler member.
Removes manual new/delete.

llvm-svn: 315225
2017-10-09 18:11:04 +00:00
Reid Kleckner 26fa1bf4da Re-land "Fix Bug 30978 by emitting cv file checksums."
This reverts r313431 and brings back r313374 with a fix to write
checksums as binary data and not ASCII hex strings.

llvm-svn: 313657
2017-09-19 18:14:45 +00:00
Eric Beckmann 913213c8ae Revert "Fix Bug 30978 by emitting cv file checksums."
This reverts commit 6389e7aa724ea7671d096f4770f016c3d86b0d54.

There is a bug in this implementation where the string value of the
checksum is outputted, instead of the actual hex bytes.  Therefore the
checksum is incorrect, and this prevent pdbs from being loaded by visual
studio.  Revert this until the checksum is emitted correctly.

llvm-svn: 313431
2017-09-16 01:14:36 +00:00
Eric Beckmann 349746f044 Fix Bug 30978 by emitting cv file checksums.
Summary:
The checksums had already been placed in the IR, this patch allows
MCCodeView to actually write it out to an MCStreamer.

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37157

llvm-svn: 313374
2017-09-15 18:20:28 +00:00
Arnaud A. de Grandmaison 6d2417924c MCObjectStreamer : fail with a diagnostic when emitting an out of range value.
We were previously silently emitting bogus data in release mode,
making it very hard to diagnose the error, or crashing with an
assert in debug mode. A proper diagnostic is now always emitted
when the value to be emitted is out of range.

llvm-svn: 303041
2017-05-15 08:43:27 +00:00
Andrew V. Tischenko 75745d0c3e This patch closes PR#32216: Better testing of schedule model instruction latencies/throughputs.
The details are here: https://reviews.llvm.org/D30941

llvm-svn: 300311
2017-04-14 07:44:23 +00:00
Weiming Zhao 74a7fa0594 Reland r298901 with modifications (reverted in r298932)
Dont emit Mapping symbols for sections that contain only data.

Summary:
Dont emit mapping symbols for sections that contain only data.

Reviewers: rengolin, weimingz, kparzysz, t.p.northover, peter.smith

Reviewed By: t.p.northover

Patched by Shankar Easwaran <shankare@codeaurora.org>

Subscribers: alekseyshl, t.p.northover, llvm-commits

Differential Revision: https://reviews.llvm.org/D30724

llvm-svn: 299392
2017-04-03 21:50:04 +00:00
Weiming Zhao da4d12a8e5 Revert "Dont emit Mapping symbols for sections that contain only data."
It breaks some lld tests.

This reverts commit 3a50eea6d9732ab40e9a7aebe6be777b53a8b35c.

llvm-svn: 298932
2017-03-28 17:15:11 +00:00
Weiming Zhao 320848458b Dont emit Mapping symbols for sections that contain only data.
Summary:
Dont emit mapping symbols for sections that contain only data.

Patched by Shankar Easwaran <shankare@codeaurora.org>

Reviewers: rengolin, peter.smith, weimingz, kparzysz, t.p.northover

Reviewed By: t.p.northover

Subscribers: t.p.northover, llvm-commits

Differential Revision: https://reviews.llvm.org/D30724

llvm-svn: 298901
2017-03-28 05:40:36 +00:00
David Blaikie 6c5bbae7b3 Check that line table entries don't spill over between sections even if they're empty at the end of a section
llvm-svn: 297922
2017-03-16 00:52:18 +00:00
Peter Collingbourne 5b75fd9e56 MC: De-duplicate the object streamer implementations of EmitFileDirective into MCObjectStreamer. NFCI.
llvm-svn: 296912
2017-03-03 21:22:06 +00:00
Rafael Espindola be99157127 Move some error handling down to MCStreamer.
This makes sure we get the same redefinition rules regardless of who
is printing (asm parser, codegen) and to what (asm, obj).

This fixes an unintentional regression in r293936.

llvm-svn: 294752
2017-02-10 15:13:12 +00:00
Oliver Stannard 268f42f1ce [Assembler] Better error messages for .org directive
Currently, the error messages we emit for the .org directive when the
expression is not absolute or is out of range do not include the line
number of the directive, so it can be hard to track down the problem if
a file contains many .org directives.

This patch stores the source location in the MCOrgFragment, so that it
can be used for diagnostics emitted during layout.

Since layout is an iterative process, and the errors are detected during
each iteration, it would have been possible for errors to be reported
multiple times. To prevent this, I've made the assembler bail out after
each iteration if any errors have been reported. This will still allow
multiple unrelated errors to be reported in the common case where they
are all detected in the first round of layout.

Differential Revision: https://reviews.llvm.org/D27411

llvm-svn: 289643
2016-12-14 10:43:58 +00:00
Eric Christopher 445c952bd0 Tidy the calls to getCurrentSection().first -> getCurrentSectionOnly to help
readability a bit.

llvm-svn: 284202
2016-10-14 05:47:37 +00:00
Reid Kleckner a9f4cc9510 [codeview] Add new directives to record inlined call site line info
Summary:
Previously we were trying to represent this with the "contains" list of
the .cv_inline_linetable directive, which was not enough information.
Now we directly represent the chain of inlined call sites, so we know
what location to emit when we encounter a .cv_loc directive of an inner
inlined call site while emitting the line table of an outer function or
inlined call site. Fixes PR29146.

Also fixes PR29147, where we would crash when .cv_loc directives crossed
sections. Now we write down the section of the first .cv_loc directive,
and emit an error if any other .cv_loc directive for that function is in
a different section.

Also fixes issues with discontiguous inlined source locations, like in
this example:

  volatile int unlikely_cond = 0;
  extern void __declspec(noreturn) abort();
  __forceinline void f() {
    if (!unlikely_cond) abort();
  }
  int main() {
    unlikely_cond = 0;
    f();
    unlikely_cond = 0;
  }

Previously our tables gave bad location information for the 'abort'
call, and the debugger wouldn't snow the inlined stack frame for 'f'.
It is important to emit good line tables for this code pattern, because
it comes up whenever an asan bug occurs in an inlined function. The
__asan_report* stubs are generally placed after the normal function
epilogue, leading to discontiguous regions of inlined code.

Reviewers: majnemer, amccarth

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D24014

llvm-svn: 280822
2016-09-07 16:15:31 +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
Simon Atanasyan eb9ed61021 [mips][ias] Support .dtprel[d]word and .tprel[d]word directives
Assembler directives .dtprelword, .dtpreldword, .tprelword, and
.tpreldword generates relocations R_MIPS_TLS_DTPREL32, R_MIPS_TLS_DTPREL64,
R_MIPS_TLS_TPREL32, and R_MIPS_TLS_TPREL64 respectively.

The main motivation for this patch is to be able to write test cases
for checking correctness of the LLD linker's behaviour.

Differential Revision: https://reviews.llvm.org/D23669

llvm-svn: 279439
2016-08-22 16:18:42 +00:00
Nirav Dave 8603062ee4 Fix branch relaxation in 16-bit mode.
Thread through MCSubtargetInfo to relaxInstruction function allowing relaxation
to generate jumps with 16-bit sized immediates in 16-bit mode.

This fixes PR22097.

Reviewers: dwmw2, tstellarAMD, craig.topper, jyknight

Subscribers: jfb, arsenm, jyknight, llvm-commits, dsanders

Differential Revision: http://reviews.llvm.org/D20830

llvm-svn: 275068
2016-07-11 14:23:53 +00:00
Petr Hosek faef3207de [MC] Rename EmitFill to emitFill
This is to match the overloaded variants as well as the new style.

Differential Revision: http://reviews.llvm.org/D20690

llvm-svn: 271359
2016-06-01 01:59:58 +00:00
Petr Hosek 67a94a795d [MC] Support symbolic expressions in assembly directives
This matches the behavior of GNU assembler which supports symbolic
expressions in absolute expressions used in assembly directives.

Differential Revision: http://reviews.llvm.org/D20752

llvm-svn: 271102
2016-05-28 05:57:48 +00:00
Petr Hosek 97859ccd51 Revert "[MC] Support symbolic expressions in assembly directives"
This reverts commit r271028, it causes the directive_fill.s to fail.

llvm-svn: 271038
2016-05-27 19:58:05 +00:00
Petr Hosek ec73d8b383 [MC] Support symbolic expressions in assembly directives
This matches the behavior of GNU assembler which supports symbolic
expressions in absolute expressions used in assembly directives.

Differential Revision: http://reviews.llvm.org/D20656

llvm-svn: 271028
2016-05-27 18:49:44 +00:00
Reid Kleckner 63d3d6df7d Revert "[MC] Support symbolic expressions in assembly directives"
This reverts commit r270786, it causes the directive_fill.s to fail.

llvm-svn: 270795
2016-05-25 23:29:08 +00:00
Petr Hosek e25837528b [MC] Support symbolic expressions in assembly directives
This matches the behavior of GNU assembler which supports symbolic
expressions in absolute expressions used in assembly directives.

Differential Revision: http://reviews.llvm.org/D20337

llvm-svn: 270786
2016-05-25 22:47:51 +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
David Majnemer c9911f28e5 [codeview] Correctly handle inlining functions post-dominated by unreachable
CodeView requires us to accurately describe the extent of the inlined
code.  We did this by grabbing the next debug location in source order
and using *that* to denote where we stopped inlining.  However, this is
not sufficient or correct in instances where there is no next debug
location or the next debug location belongs to the start of another
function.

To get this correct, use the end symbol of the function to denote the
last possible place the inlining could have stopped at.

llvm-svn: 259548
2016-02-02 19:22:34 +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