Commit Graph

62 Commits

Author SHA1 Message Date
Reid Kleckner 3acdc67734 [CodeView] Lower __restrict and other pointer qualifiers correctly
Qualifiers on a pointer or reference type may apply to either the
pointee or the pointer itself. Consider 'const char *' and 'char *
const'. In the first example, the pointee data may not be modified
without casts, and in the second example, the pointer may not be updated
to point to new data.

In the general case, qualifiers are applied to types with LF_MODIFIER
records, which support the usual const and volatile qualifiers as well
as the __unaligned extension qualifier.

However, LF_POINTER records, which are used for pointers, references,
and member pointers, have flags for qualifiers applying to the
*pointer*. In fact, this is the only way to represent the restrict
qualifier, which can only apply to pointers, and cannot qualify regular
data types.

This patch causes LLVM to correctly fold 'const' and 'volatile' pointer
qualifiers into the pointer record, as well as adding support for
'__restrict' qualifiers in the same place.

Based on a patch from Aaron Smith

Differential Revision: https://reviews.llvm.org/D43060

llvm-svn: 326260
2018-02-27 22:08:15 +00:00
Zachary Turner 048f8f99bf [CodeView] Teach clang to emit the .debug$H COFF section.
Currently this is an LLVM extension to the COFF spec which is
experimental and intended to speed up linking.  For now it is
behind a hidden cl::opt flag, but in the future we can move it
to a "real" cc1 flag and have the driver pass it through whenever
it is appropriate.

The patch to actually make use of this section in lld will come
in a followup.

Differential Revision: https://reviews.llvm.org/D40917

llvm-svn: 320649
2017-12-13 22:33:58 +00:00
Zachary Turner ca6dbf1440 Split TypeTableBuilder into two classes.
llvm-svn: 319456
2017-11-30 18:39:50 +00:00
Reid Kleckner bc6f52da82 [codeview] Merge file checksum entries for DIFiles with the same absolute path
Change the map key from DIFile* to the absolute path string. Computing
the absolute path isn't expensive because we already have a map that
caches the full path keyed on DIFile*.

llvm-svn: 317041
2017-10-31 21:52:15 +00:00
Adrian McCarthy d91bf3998f Mark static member functions as static in CodeViewDebug
Summary:
To improve CodeView quality for static member functions, we need to make the
static explicit.  In addition to a small change in LLVM's CodeViewDebug to
return the appropriate MethodKind, this requires a small change in Clang to
note the staticness in the debug info metadata.

Subscribers: aprantl, hiraditya

Differential Revision: https://reviews.llvm.org/D37715

llvm-svn: 313192
2017-09-13 20:53:55 +00:00
Reid Kleckner e33c94f1b0 Add llvm.codeview.annotation to implement MSVC __annotation
Summary:
This intrinsic represents a label with a list of associated metadata
strings. It is modelled as reading and writing inaccessible memory so
that it won't be removed as dead code. I think the intention is that the
annotation strings should appear at most once in the debug info, so I
marked it noduplicate. We are allowed to inline code with annotations as
long as we strip the annotation, but that can be done later.

Reviewers: majnemer

Subscribers: eraman, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D36904

llvm-svn: 312569
2017-09-05 20:14:58 +00:00
Reid Kleckner 08f5fd51cc [codeview] Generalize DIExpression parsing to handle load chains
Summary:
Hopefully this also clarifies exactly when and why we're rewriting
certiain S_LOCALs using reference types: We're using the reference type
to stand in for a zero-offset load.

Reviewers: inglorion

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37309

llvm-svn: 312247
2017-08-31 15:56:49 +00:00
Bob Haarman 223303c5a3 Reland r311957 [codeview] support more DW_OPs for more complete debug info
Summary:
Some variables show up in Visual Studio as "optimized out" even in -O0
-Od builds. This change fixes two issues that would cause this to
happen. The first issue is that not all DIExpressions we generate were
recognized by the CodeView writer. This has been addressed by adding
support for DW_OP_constu, DW_OP_minus, and DW_OP_plus. The second
issue is that we had no way to encode DW_OP_deref in CodeView. We get
around that by changinge the type we encode in the debug info to be
a reference to the type in the source code.

This fixes PR34261.

The reland adds two extra checks to the original: It checks if the
DbgVariableLocation is valid before checking any of its fields, and
it only emits ranges with nonzero registers.

Reviewers: aprantl, rnk, zturner

Reviewed By: rnk

Subscribers: mgorny, llvm-commits, aprantl, hiraditya

Differential Revision: https://reviews.llvm.org/D36907

llvm-svn: 312034
2017-08-29 20:59:25 +00:00
Bob Haarman 0bf0d66682 Revert "[codeview] support more DW_OPs for more complete debug info"
This reverts commit e160912f53f047bc97e572add179e08e33f4df48.

llvm-svn: 311977
2017-08-29 04:08:31 +00:00
Bob Haarman b2a04a1513 [codeview] support more DW_OPs for more complete debug info
Summary:
Some variables show up in Visual Studio as "optimized out" even in -O0
-Od builds. This change fixes two issues that would cause this to
happen. The first issue is that not all DIExpressions we generate were
recognized by the CodeView writer. This has been addressed by adding
support for DW_OP_constu, DW_OP_minus, and DW_OP_plus. The second
issue is that we had no way to encode DW_OP_deref in CodeView. We get
around that by changinge the type we encode in the debug info to be
a reference to the type in the source code.

This fixes PR34261.

Reviewers: aprantl, rnk, zturner

Reviewed By: rnk

Subscribers: mgorny, llvm-commits, aprantl, hiraditya

Differential Revision: https://reviews.llvm.org/D36907

llvm-svn: 311957
2017-08-29 00:06:59 +00:00
Zachary Turner a7b041748d [CodeView] Don't output S_UDT symbols for forward decls.
S_UDT symbols are the debugger's "index" for all the structs,
typedefs, classes, and enums in a program.  If any of those
structs/classes don't have a complete declaration, or if there
is a typedef to something that doesn't have a complete definition,
then emitting the S_UDT is unhelpful because it doesn't give
the debugger enough information to do anything useful.  On the
other hand, it results in a huge size blow-up in the resulting
PDB, which is exacerbated by an order of magnitude when linking
with /DEBUG:FASTLINK.

With this patch, we drop S_UDT records for types that refer either
directly or indirectly (e.g. through a typedef, pointer, etc) to
a class/struct/union/enum without a complete definition.  This
brings us about 50% of the way towards parity with /DEBUG:FASTLINK
PDBs generated from cl-compiled object files.

Differential Revision: https://reviews.llvm.org/D37162

llvm-svn: 311904
2017-08-28 18:49:04 +00:00
Reid Kleckner 45a7462094 [codeview] Use the first valid source location at the top of every MBB
If the instructions at the beginning of the block have no location,
we're better off using the location of the first instruction in the
current basic block. At the very least, that instruction post-dominates
this one, whereas if we don't emit a .cv_loc directive, we end up using
the potentially invalid location that falls through from the previous
block.

We could probably do better here by emitting some kind of ".cv_loc end"
directive that stops the line table entry of the previous .cv_loc
directive from bleeding out of its basic block. This would improve the
line table when an entire MBB has no valid location info.

llvm-svn: 306889
2017-06-30 21:33:44 +00:00
Eugene Zelenko fb69e66cff [CodeGen] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 304839
2017-06-06 22:22:41 +00:00
Zachary Turner 8c099fe06e [CodeView] Rename ModuleDebugFragment -> DebugSubsection.
This is more concise, and matches the terminology used in other
parts of the codebase more closely.

llvm-svn: 304218
2017-05-30 16:36:15 +00:00
Zachary Turner 67c5601404 Rename some PDB classes.
We have a lot of very similarly named classes related to
dealing with module debug info.  This patch has NFC, it just
renames some classes to be more descriptive (albeit slightly
more to type).  The mapping from old to new class names is as
follows:

   Old          |        New
ModInfo         | DbiModuleDescriptor
ModuleSubstream | ModuleDebugFragment
ModStream       | ModuleDebugStream

With the corresponding Builder classes renamed accordingly.

Differential Revision: https://reviews.llvm.org/D32506

llvm-svn: 301555
2017-04-27 16:11:19 +00:00
David Blaikie b2fbb4b276 Refactor DebugHandlerBase a bit to common non-debug-having-function filtering
llvm-svn: 295354
2017-02-16 18:48:33 +00:00
Matthias Braun ef331eff5a Move VariableDbgInfo from MachineModuleInfo to MachineFunction
VariableDbgInfo is per function data, so it makes sense to have it with
the function instead of the module.

This is a necessary step to have machine module passes work properly.

Differential Revision: https://reviews.llvm.org/D27186

llvm-svn: 288292
2016-11-30 23:48:50 +00:00
Zachary Turner 4efa0a4201 [CodeView] Hook up CodeViewRecordIO to type serialization path.
Previously support had been added for using CodeViewRecordIO
to read (deserialize) CodeView type records.  This patch adds
support for writing those same records.  With this patch,
reading and writing of CodeView type records finally uses a single
codepath.

Differential Revision: https://reviews.llvm.org/D26253

llvm-svn: 286304
2016-11-08 22:24:53 +00:00
Reid Kleckner 2b3e6428e5 [codeview] Translate bitpiece metadata to DEFRANGE_SUBFIELD* records
This allows LLVM to describe locations of aggregate variables that have
been split by SROA.

Fixes PR29141

Reviewers: amccarth, majnemer

Differential Revision: https://reviews.llvm.org/D25253

llvm-svn: 283388
2016-10-05 21:21:33 +00:00
Adrian McCarthy c64acfd4c2 Emit S_COMPILE3 CodeView record
CodeView has an S_COMPILE3 record to identify the compiler and source language of the compiland.  This record comes first in the debug$S section for the compiland. The debuggers rely on this record to know the source language of the code.

There was a little test fallout from introducing a new record into the symbols subsection.

Differential Revision: https://reviews.llvm.org/D24317

llvm-svn: 281990
2016-09-20 17:20:51 +00:00
Peter Collingbourne d4135bbc30 DebugInfo: New metadata representation for global variables.
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.

Fixes PR30362. A program for upgrading test cases is attached to that
bug.

Differential Revision: http://reviews.llvm.org/D20147

llvm-svn: 281284
2016-09-13 01:12:59 +00:00
Zachary Turner c6d54da891 [pdb] Write PDB TPI Stream from Yaml.
This writes the full sequence of type records described in
Yaml to the TPI stream of the PDB file.

Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D24316

llvm-svn: 281063
2016-09-09 17:46:17 +00:00
Reid Kleckner 9dac47319d [codeview] Emit vtable shape information
The shape of the vtable is passed down as the size of the
__vtbl_ptr_type. This special pointer type appears both as the pointee
type of the vptr type, and by itself in every dynamic class. For classes
with multiple vtables, only the shape of the primary vftable is
included, as the shape of all secondary vftables will be the same as in
the base class.

Fixes PR28150

llvm-svn: 280254
2016-08-31 15:59:30 +00:00
Reid Kleckner c29b4f07f9 [codeview] Shrink inlined call site line info tables
For a fully inlined call chain like a -> b -> c -> d, we were emitting
line info for 'd' 3 separate times: once for d's actual InlineSite line
table, and twice for 'b' and 'c'. This is particularly inefficient when
all these functions are in different headers, because now we need to
encode the file change. Windbg was coping with our suboptimal output, so
this should not be noticeable from the debugger.

llvm-svn: 275502
2016-07-14 23:47:15 +00:00
Adrian McCarthy 820ca5404c Retry: "Emit CodeView type records for nested classes."
Now with a corrected test to account for a recently supported properties bit in the debug info of a struct.

Original review: http://reviews.llvm.org/D21939

This reverts commit 970c3fd497a28d25dd69526eb52594a696c37968.

llvm-svn: 274661
2016-07-06 19:49:51 +00:00