Commit Graph

558 Commits

Author SHA1 Message Date
Saleem Abdulrasool 4d6ed7c778 IAS: correct debug line info for asm macros
Correct the line information generation for preprocessed assembly.  Although we
tracked the source information for the macro instantiation, we failed to account
for the fact that we were instantiating a macro, which is populated into a new
buffer and that the line information would be relative to the definition rather
than the actual instantiation location.  This could cause the line number
associated with the statement to be very high due to wrapping of the difference
calculated for the preprocessor line information emitted into the stream.
Properly calculate the line for the macro instantiation, referencing the line
where the macro is actually used as GCC/gas do.

The test case uses x86, though the same problem exists on any other target using
the LLVM IAS.

llvm-svn: 224810
2014-12-24 06:32:43 +00:00
Adrian Prantl 3026a54aa2 Debug Info: In symmetry to DW_TAG_pointer_type, do not emit the byte size
of a DW_TAG_ptr_to_member_type.
This restores the behavior from before r224780-r224781.

llvm-svn: 224799
2014-12-24 01:17:51 +00:00
Chandler Carruth c7d1e24b34 Revert r224739: Debug info: Teach SROA how to update debug info for
fragmented variables.

This caused codegen to start crashing when we built somewhat large
programs with debug info and optimizations. 'check-msan' hit in, and
I suspect a bootstrap would as well. I mailed a test case to the
review thread.

llvm-svn: 224750
2014-12-23 02:58:14 +00:00
Adrian Prantl a47ace5901 Debug info: Teach SROA how to update debug info for fragmented variables.
This allows us to generate debug info for extremely advanced code such as

  typedef struct { long int a; int b;} S;

  int foo(S s) {
    return s.b;
  }

which at -O1 on x86_64 is codegen'd into

  define i32 @foo(i64 %s.coerce0, i32 %s.coerce1) #0 {
    ret i32 %s.coerce1, !dbg !24
  }

with this patch we emit the following debug info for this

  TAG_formal_parameter [3]
    AT_location( 0x00000000
                 0x0000000000000000 - 0x0000000000000006: rdi, piece 0x00000008, rsi, piece 0x00000004
                 0x0000000000000006 - 0x0000000000000008: rdi, piece 0x00000008, rax, piece 0x00000004 )
                 AT_name( "s" )
                 AT_decl_file( "/Volumes/Data/llvm/_build.ninja.release/test.c" )

Thanks to chandlerc, dblaikie, and echristo for their feedback on all
previous iterations of this patch!

llvm-svn: 224739
2014-12-22 22:26:00 +00:00
David Blaikie 8b979f01c6 PR21875: codegen for non-type template parameters of nullptr_t type
llvm-svn: 224399
2014-12-17 00:43:22 +00:00
Duncan P. N. Exon Smith be7ea19b58 IR: Make metadata typeless in assembly
Now that `Metadata` is typeless, reflect that in the assembly.  These
are the matching assembly changes for the metadata/value split in
r223802.

  - Only use the `metadata` type when referencing metadata from a call
    intrinsic -- i.e., only when it's used as a `Value`.

  - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode`
    when referencing it from call intrinsics.

So, assembly like this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata !{i32 %v}, metadata !0)
      call void @llvm.foo(metadata !{i32 7}, metadata !0)
      call void @llvm.foo(metadata !1, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{metadata !3}, metadata !0)
      ret void, !bar !2
    }
    !0 = metadata !{metadata !2}
    !1 = metadata !{i32* @global}
    !2 = metadata !{metadata !3}
    !3 = metadata !{}

turns into this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata i32 %v, metadata !0)
      call void @llvm.foo(metadata i32 7, metadata !0)
      call void @llvm.foo(metadata i32* @global, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{!3}, metadata !0)
      ret void, !bar !2
    }
    !0 = !{!2}
    !1 = !{i32* @global}
    !2 = !{!3}
    !3 = !{}

I wrote an upgrade script that handled almost all of the tests in llvm
and many of the tests in cfe (even handling many `CHECK` lines).  I've
attached it (or will attach it in a moment if you're speedy) to PR21532
to help everyone update their out-of-tree testcases.

This is part of PR21532.

llvm-svn: 224257
2014-12-15 19:07:53 +00:00
Adrian Prantl b9a88e2942 Fix a bug when pretty-printing DW_OP_deref.
llvm-svn: 223493
2014-12-05 18:19:38 +00:00
Adrian Prantl 36d07d153e Regenerate this stale testcase from source.
llvm-svn: 223492
2014-12-05 18:19:32 +00:00
Frederic Riss 2700d03da5 Add a test for r222029 that doesn't rely on the default target being a COFF platform.
llvm-svn: 222041
2014-11-14 21:23:26 +00:00
Frederic Riss 0f7abef2cf Add an assert and a test that verify r221709's fix.
llvm-svn: 221854
2014-11-13 03:20:23 +00:00
David Blaikie 3a443c29b9 Provide gmlt-like inline scope information in the skeleton CU to facilitate symbolication without needing the .dwo files
Clang -gsplit-dwarf self-host -O0, binary increases by 0.0005%, -O2,
binary increases by 25%.

A large binary inside Google, split-dwarf, -O0, and other internal flags
(GDB index, etc) increases by 1.8%, optimized build is 35%.

The size impact may be somewhat greater in .o files (I haven't measured
that much - since the linked executable -O0 numbers seemed low enough)
due to relocations. These relocations could be removed if we taught the
llvm-symbolizer to handle indexed addressing in the .o file (GDB can't
cope with this just yet, but GDB won't be reading this info anyway).
Also debug_ranges could be shared between .o and .dwo, though ideally
debug_ranges would get a schema that could used index(+offset)
addressing, and move to the .dwo file, then we'd be back to sharing
addresses in the address pool again.

But for now, these sizes seem small enough to go ahead with this.

Verified that no other DW_TAGs are produced into the .o file other than
subprograms and inlined_subroutines.

llvm-svn: 221306
2014-11-04 22:12:25 +00:00
David Blaikie 4729c78bc0 Test 221067 in a fixed-target test so as not to fail on targets with different DWARF encodings
llvm-svn: 221071
2014-11-01 23:50:59 +00:00
David Blaikie 983bfea0d0 Remove DwarfUnit::LabelEnd in favor of computing the length of the section directly
This was a compile-unit specific label (unused in type units) and seems
unnecessary anyway when we can more easily directly compute the size of
the compile unit.

llvm-svn: 221067
2014-11-01 23:07:14 +00:00
David Blaikie 49cfc8ca8e DebugInfo: Simplify/tidy/correct global variable decl/def emission handling.
This fixes a bug (introduced by fixing the IR emitted from Clang where
the definition of a static member would be scoped within the class,
rather than within its lexical decl context) where the definition of a
static variable would be placed inside a class.

It also improves source fidelity by scoping static class member
definitions inside the lexical decl context in which tehy are written
(eg: namespace n { class foo { static int i; } int foo::i; } - the
definition of 'i' will be within the namespace 'n' in the DWARF output
now).

Lastly, and the original goal, this reduces debug info size slightly
(and makes debug info easier to read, etc) by placing the definitions of
non-member global variables within their namespace, rather than using a
separate namespace-scoped declaration along with a definition at global
scope.

Based on patches and discussion with Frédéric.

llvm-svn: 220497
2014-10-23 19:12:43 +00:00
Frederic Riss e939b43aa4 [dwarfdump] Dump DW_AT_ranges values inline in the debug_info dump.
The output looks like that:
                      DW_AT_ranges [FORM_data4]    (0x00000000
                         [0x00000001000024a0 - 0x00000001000024c2)
                         [0x0000000100002505 - 0x000000010000268b))

Differential Revision: http://reviews.llvm.org/D5712

llvm-svn: 220466
2014-10-23 04:08:34 +00:00
Rafael Espindola c606bfe660 Fix a bit of confusion about .set and produce more readable assembly.
Every target we support has support for assembly that looks like

a = b - c
.long a

What is special about MachO is that the above combination suppresses the
production of a relocation.

With this change we avoid producing the intermediary labels when they don't
add any value.

llvm-svn: 220256
2014-10-21 01:17:30 +00:00
Frederic Riss d4de180e19 [dwarfdump] Resolve also variable specifications/abstract_origins.
DW_AT_specification and DW_AT_abstract_origin resolving was only performed
on subroutine DIEs because it used the getSubroutineName method. Introduce
a more generic getName() and use it to dump the reference attributes.

Testcases have been updated to check the printed names instead of the offsets
except when the name could be ambiguous.

Reviewers: dblaikie, samsonov

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5625

llvm-svn: 219506
2014-10-10 15:51:02 +00:00
David Majnemer 5fbe324ff9 llvm-dwarfdump: Add support for some COFF relocations
DWARF in COFF utilizes several relocations.  Implement support for them
in RelocVisitor to support llvm-dwarfdump.

llvm-svn: 219280
2014-10-08 06:38:50 +00:00
Eric Christopher 1452c8e640 Add some tests for RelocVisitor.
Patch by Charlie Turner.

llvm-svn: 219107
2014-10-06 06:52:52 +00:00
Frederic Riss d1cfc3c791 [dwarfdump] Print the name for referenced specification of abstract_origin DIEs.
Reviewers: dblaikie, samsonov, echristo, aprantl

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5466

llvm-svn: 219099
2014-10-06 03:36:31 +00:00
Duncan P. N. Exon Smith 176b691d32 Revert "Revert "DI: Fold constant arguments into a single MDString""
This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash.  The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).

Original commit message follows.

--

This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

llvm-svn: 219010
2014-10-03 20:01:09 +00:00
Duncan P. N. Exon Smith 786cd049fc Revert "DI: Fold constant arguments into a single MDString"
This reverts commit r218914 while I investigate some bots.

llvm-svn: 218918
2014-10-02 22:15:31 +00:00
Duncan P. N. Exon Smith 571f97bd90 DI: Fold constant arguments into a single MDString
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

llvm-svn: 218914
2014-10-02 21:56:57 +00:00
Adrian Prantl 87b7eb9d0f Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

Note: I accidentally committed a bogus older version of this patch previously.
llvm-svn: 218787
2014-10-01 18:55:02 +00:00
Adrian Prantl b458dc2eee Revert r218778 while investigating buldbot breakage.
"Move the complex address expression out of DIVariable and into an extra"

llvm-svn: 218782
2014-10-01 18:10:54 +00:00
Adrian Prantl 25a7174e7a Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

llvm-svn: 218778
2014-10-01 17:55:39 +00:00
David Blaikie 32b0f365a2 Implement DW_TAG_subrange_type with DW_AT_count rather than DW_AT_upper_bound
This allows proper disambiguation of unbounded arrays and arrays of zero
bound ("struct foo { int x[]; };" and "struct foo { int x[0]; }"). GCC
instead produces an upper bound of -1 in the latter situation, but count
seems tidier. This way lower_bound is provided if it's not the language
default and count is provided if the count is known, otherwise it's
omitted. Simple.

If someone wants to look at rdar://problem/12566646 and see if this
change is acceptable to that bug/fix, that might be helpful (see the
empty-and-one-elem-array.ll test case which cites that radar).

llvm-svn: 218726
2014-10-01 00:56:55 +00:00
NAKAMURA Takumi 614f1001ec llvm/test/DebugInfo/X86/gmlt.test: Get rid of %llc_dwarf. It should not be used with -mtriple.
Also, remove object-emission. test/DebugInfo/X86 doesn't require it.

llvm-svn: 218722
2014-10-01 00:29:16 +00:00
David Blaikie 515387569a Adjust test case addition in r218702 so as not to fail when the X86 target isn't built.
llvm-svn: 218708
2014-09-30 22:02:27 +00:00
Frederic Riss 220fa48491 Fix a test introduced in r218246 to work also on Windows.
llvm-svn: 218255
2014-09-22 16:17:32 +00:00
Frederic Riss 955724e3f5 [dwarfdump] Dump full filenames as DW_AT_(decl|call)_file attribute values
Reviewers: dblaikie samsonov

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5192

llvm-svn: 218246
2014-09-22 12:36:04 +00:00
David Majnemer fb83977538 Update tests which broke from r218189
llvm-svn: 218191
2014-09-20 21:18:43 +00:00
David Blaikie c42f9ac01c DebugInfo: Do not use DW_FORM_GNU_addr_index in skeleton CUs, GDB 7.8 errors on this.
It's probably not a huge deal to not do this - if we could, maybe the
address could be reused by a subprogram low_pc and avoid an extra
relocation, but it's just one per CU at best.

llvm-svn: 217338
2014-09-07 17:31:42 +00:00
Saleem Abdulrasool fcefa21b08 MC: correct DWARF line info for PE/COFF
DWARF address ranges contain a reference to the debug_info section.  This offset
is an absolute relocation except on non-PE/COFF targets where it is section
relative.  We would emit this incorrectly, and trying to map the debug info from
the address would fail.

llvm-svn: 217317
2014-09-06 19:57:48 +00:00
Frederic Riss 0982e69fb8 [dwarfdump] Dump DW_AT_(decl|call)_line attribute values as decimal values.
llvm-svn: 217232
2014-09-05 07:21:50 +00:00
Saleem Abdulrasool 5c70de1072 MC: correct DWARF header for PE/COFF assembly input
The header contains an offset to the DWARF line table for the CU.  The offset
must be section relative for COFF and absolute for others.  The non-assembly
code path for the DWARF header generation already has the correct emission for
the headers.  This corrects the assembly input path.

This was identified by BFD objecting to the LLVM generated DWARF information.

llvm-svn: 217222
2014-09-05 04:15:00 +00:00
Frederic Riss 878065bb21 [ dwarfdump ] Add symbolic dump of known DWARF attribute values.
Reviewed By: dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5187

llvm-svn: 217186
2014-09-04 19:39:20 +00:00
David Blaikie 6a150a87ef DebugInfo: Elide lexical scopes which only contain other (inline or lexical) scopes.
DW_TAG_lexical_scopes inform debuggers about the instruction range for
which a given variable (or imported declaration/module/etc) is valid. If
the scope doesn't itself contain any such entities, it's a waste of
space and should be omitted.

We were correctly doing this for entirely empty leaves, but not for
intermediate nodes.

Reduces total (not just debug sections) .o file size for a bootstrap
-gmlt LLVM by 22% and bootstrap -gmlt clang executable by 13%. The wins
for a full -g build will be less as a % (and in absolute terms), but
should still be substantial - with some of that win being fewer
relocations, thus more substantiall reducing link times than fewer bytes
alone would have.

llvm-svn: 216861
2014-08-31 21:26:22 +00:00
Adrian Prantl daedfda892 Debug info: Add a new explicit DIDescriptor flag for the "public" access
specifier and change the default behavior to only emit the
DW_AT_accessibility(public) attribute when the isPublic() is explicitly
set.

rdar://problem/18154959

llvm-svn: 216799
2014-08-29 22:44:07 +00:00
Frederic Riss aaae87e5ab Remove unnecessary regex in test pattern per dblaikie suggestion.
llvm-svn: 216733
2014-08-29 15:32:15 +00:00
Frederic Riss 5732301afb Use DwarfDebug::attachLowHighPC for the compilation unit DIE.
llvm-svn: 216719
2014-08-29 09:00:26 +00:00
David Blaikie c13bc97e58 Remove type unit skeletons. GDB no longer needs them & this saves a heap of space.
llvm-svn: 216521
2014-08-27 05:04:14 +00:00
David Blaikie b3833ef0c1 Fix a couple of debug info test cases to match the metadata schema change in r216239
Found these while testing something else.

llvm-svn: 216505
2014-08-27 00:04:16 +00:00
David Blaikie 2f3f76fdb1 Use DILexicalBlockFile, rather than DILexicalBlock, to track discriminator changes to ensure discriminator changes don't introduce new DWARF DW_TAG_lexical_blocks.
Somewhat unnoticed in the original implementation of discriminators, but
it could cause instructions to end up in new, small,
DW_TAG_lexical_blocks due to the use of DILexicalBlock to track
discriminator changes.

Instead, use DILexicalBlockFile which we already use to track file
changes without introducing new scopes, so it works well to track
discriminator changes in the same way.

llvm-svn: 216239
2014-08-21 22:45:21 +00:00
Juergen Ributzka 89d187b387 Reapply [FastISel][X86] Use XOR to materialize the "0" value (r215594).
Note: This was originally reverted to track down a buildbot error. Reapply
without any modifications.

llvm-svn: 216011
2014-08-19 19:44:10 +00:00
Juergen Ributzka 790bacf232 Revert several FastISel commits to track down a buildbot error.
This reverts:
r215595 "[FastISel][X86] Add large code model support for materializing floating-point constants."
r215594 "[FastISel][X86] Use XOR to materialize the "0" value."
r215593 "[FastISel][X86] Emit more efficient instructions for integer constant materialization."
r215591 "[FastISel][AArch64] Make use of the zero register when possible."
r215588 "[FastISel] Let the target decide first if it wants to materialize a constant."
r215582 "[FastISel][AArch64] Cleanup constant materialization code. NFCI."

llvm-svn: 215673
2014-08-14 19:56:28 +00:00
Juergen Ributzka ba8b79e932 [FastISel][X86] Use XOR to materialize the "0" value.
llvm-svn: 215594
2014-08-13 22:22:17 +00:00
Adrian Prantl 9724b5c9a4 DebugLocEntry: Restore the comparison predicate from before the
refactoring in 215384. This way it can unique multiple entries describing
the same piece even if they don't have the exact same location.
(The same piece may get merged in and be added from OpenRanges).
There ought to be a more elegant solution for this, though.

llvm-svn: 215418
2014-08-12 01:07:53 +00:00
NAKAMURA Takumi 15ac9af4f4 Fix llvm/test/DebugInfo/X86/recursive_inlining.ll to use %llc_dwarf.
llvm-svn: 215181
2014-08-08 02:24:05 +00:00
David Blaikie 09fdfabdda DebugInfo: Fix overwriting/loss of inlined arguments to recursively inlined functions.
Due to an unnecessary special case, inlined arguments that happened to
be from the same function as they were inlined into were misclassified
as non-inline arguments and would overwrite the non-inlined arguments.

Assert that we never overwrite a function's arguments, and stop
misclassifying inlined arguments as non-inline arguments to fix this
issue.

Excuse the rather crappy test case - handcrafted IR might do better, or
someone who understands better how to tickle the inliner to create a
recursive inlining situation like this (though it may also be necessary
to tickle the variable in a particular way to cause it to be recorded in
the MMI side table and go down this particular path for location
information).

llvm-svn: 215157
2014-08-07 22:22:49 +00:00
David Blaikie fb0412f039 DebugInfo: Assert that any CU for which debug_loc lists are emitted, has at least one range.
This was coming in weird debug info that had variables (and hence
debug_locs) but was in GMLT mode (because it was missing the 13th field
of the compile_unit metadata) so no ranges were constructed. We should
always have at least one range for any CU with a debug_loc in it -
because the range should cover the debug_loc.

The assertion just ensures that the "!= 1" range case inside the
subsequent loop doesn't get entered for the case where there are no
ranges at all, which should never reach here in the first place.

llvm-svn: 214939
2014-08-06 00:21:25 +00:00
David Blaikie cabf54a313 DebugInfo: Fix a bunch of tests that, owing to their compile_unit metadata not including a 13th field, had some subtle behavior.
Without the 13th field, the "emission kind" field defaults to 0 (which
is not equal to either of the values of the emission kind enum (1 ==
full debug info, 2 == line tables only)).

In this particular instance, the comparison with "FullDebugInfo" was
done when adding elements to the ranges list - so for these test cases
no values were added to the ranges list.

This got weirder when emitting debug_loc entries as the addresses should
be relative to the range of the CU if the CU has only one range (the
reasonable assumption is that if we're emitting debug_loc lists for a CU
that CU has at least one range - but due to the above situation, it has
zero) so the ranges were emitted relative to the start of the section
rather than relative to the start of the CU's singular range.

Fix these tests by accounting for the difference in the description of
debug_loc entries (in some cases making the test ignorant to these
differences, in others adding the extra label difference expression,
etc) or the presence/absence of high/low_pc on the CU, and add the 13th
field to their CUs to enable proper "full debug info" emission here.

In a future commit I'll fix up a bunch of other test cases that are not
so rigorously depending on this behavior, but still doing similarly
weird things due to the missing 13th field.

llvm-svn: 214937
2014-08-05 23:57:31 +00:00
Adrian Prantl d13dba42f6 Cleanup this test some more.
llvm-svn: 214591
2014-08-01 23:01:32 +00:00
Adrian Prantl a717a6da3d Add the missing target triple to this testcase.
llvm-svn: 214590
2014-08-01 23:01:30 +00:00
Adrian Prantl b1416837f9 Debug info: Infrastructure to support debug locations for fragmented
variables (for example, by-value struct arguments passed in registers, or
large integer values split across several smaller registers).
On the IR level, this adds a new type of complex address operation OpPiece
to DIVariable that describes size and offset of a variable fragment.
On the DWARF emitter level, all pieces describing the same variable are
collected, sorted and emitted as DWARF expressions using the DW_OP_piece
and DW_OP_bit_piece operators.

http://reviews.llvm.org/D3373
rdar://problem/15928306

What this patch doesn't do / Future work:
- This patch only adds the backend machinery to make this work, patches
  that change SROA and SelectionDAG's type legalizer to actually create
  such debug info will follow. (http://reviews.llvm.org/D2680)
- Making the DIVariable complex expressions into an argument of dbg.value
  will reduce the memory footprint of the debug metadata.
- The sorting/uniquing of pieces should be moved into DebugLocEntry,
  to facilitate the merging of multi-piece entries.

llvm-svn: 214576
2014-08-01 22:11:58 +00:00
Rafael Espindola 464fe024c5 Use "weak alias" instead of "alias weak"
Before this patch we had

@a = weak global ...
but
@b = alias weak ...

The patch changes aliases to look more like global variables.

Looking at some really old code suggests that the reason was that the old
bison based parser had a reduction for alias linkages and another one for
global variable linkages. Putting the alias first avoided the reduce/reduce
conflict.

The days of the old .ll parser are long gone. The new one parses just "linkage"
and a later check is responsible for deciding if a linkage is valid in a
given context.

llvm-svn: 214355
2014-07-30 22:51:54 +00:00
David Blaikie 29459ae83c Reapply "DebugInfo: Don't put fission type units in comdat sections."
This recommits r208930, r208933, and r208975 (by reverting r209338) and
reverts r209529 (the FIXME to readd this functionality once the tools
were fixed) now that DWP has been fixed to cope with a single section
for all fission type units.

Original commit message:

"Since type units in the dwo file are handled by a debug aware tool,
they don't need to leverage the ELF comdat grouping to implement
deduplication. Avoid creating all the .group sections for these as a
space optimization."

llvm-svn: 213956
2014-07-25 17:11:58 +00:00
David Blaikie 2f04011435 Recommit r212203: Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information.
Reverted by Eric Christopher (Thanks!) in r212203 after Bob Wilson
reported LTO issues. Duncan Exon Smith and Aditya Nandakumar helped
provide a reduced reproduction, though the failure wasn't too hard to
guess, and even easier with the example to confirm.

The assertion that the subprogram metadata associated with an
llvm::Function matches the scope data referenced by the DbgLocs on the
instructions in that function is not valid under LTO. In LTO, a C++
inline function might exist in multiple CUs and the subprogram metadata
nodes will refer to the same llvm::Function. In this case, depending on
the order of the CUs, the first intance of the subprogram metadata may
not be the one referenced by the instructions in that function and the
assertion will fail.

A test case (test/DebugInfo/cross-cu-linkonce-distinct.ll) is added, the
assertion removed and a comment added to explain this situation.

This was then reverted again in r213581 as it caused PR20367. The root
cause of this was the early exit in LiveDebugVariables meant that
spurious DBG_VALUE intrinsics that referenced dead variables were not
removed, causing an assertion/crash later on. The fix is to have
LiveDebugVariables strip all DBG_VALUE intrinsics in functions without
debug info as they're not needed anyway. Test case added to cover this
situation (that occurs when a debug-having function is inlined into a
nodebug function) in test/DebugInfo/X86/nodebug_with_debug_loc.ll

Original commit message:

If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.

While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.

Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.

Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).

llvm-svn: 213952
2014-07-25 16:10:16 +00:00
David Blaikie 48af9c3527 DebugInfo: Fix up some test cases to have more correct debug info metadata.
* Add CUs to the named CU node
* Add missing DW_TAG_subprogram nodes
* Add llvm::Functions to the DW_TAG_subprogram nodes

This cleans up the tests so that they don't break under a
soon-to-be-made change that is more strict about such things.

llvm-svn: 213951
2014-07-25 16:05:18 +00:00
David Blaikie 26f2268cc5 Revert "Recommit r212203: Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information."
This reverts commit r212649 while I investigate/reduce/etc PR20367.

llvm-svn: 213581
2014-07-21 20:45:59 +00:00
Saleem Abdulrasool 7d09530cef MC: correct DWARF header for PE/COFF assembly input
The header contains an offset to the DWARF abbreviations for the CU.  The offset
must be section relative for COFF and absolute for others.  The non-assembly
code path for the DWARF header generation already had the correct emission for
the headers.  This corrects just the assembly path.  Due to the invalid
relocation, processing of the debug information would halt previously on the
first assembly input as the associated abbreviations would be out of range as
they would have the location increased by image base and the section offset.

This address PR20332.

llvm-svn: 213275
2014-07-17 16:27:44 +00:00
David Blaikie 029bd3350e Recommit r212203: Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information.
Reverted by Eric Christopher (Thanks!) in r212203 after Bob Wilson
reported LTO issues. Duncan Exon Smith and Aditya Nandakumar helped
provide a reduced reproduction, though the failure wasn't too hard to
guess, and even easier with the example to confirm.

The assertion that the subprogram metadata associated with an
llvm::Function matches the scope data referenced by the DbgLocs on the
instructions in that function is not valid under LTO. In LTO, a C++
inline function might exist in multiple CUs and the subprogram metadata
nodes will refer to the same llvm::Function. In this case, depending on
the order of the CUs, the first intance of the subprogram metadata may
not be the one referenced by the instructions in that function and the
assertion will fail.

A test case (test/DebugInfo/cross-cu-linkonce-distinct.ll) is added, the
assertion removed and a comment added to explain this situation.

Original commit message:

If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.

While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.

Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.

Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).

llvm-svn: 212649
2014-07-09 21:02:41 +00:00
Eric Christopher 09f7131984 Temporarily revert "Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information." as it appears to be breaking some LTO constructs.
This reverts commit r212203.

llvm-svn: 212298
2014-07-03 22:24:54 +00:00
David Blaikie d47fb5b339 Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information.
If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.

While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.

Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.

Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).

llvm-svn: 212203
2014-07-02 18:31:35 +00:00
Adrian Prantl da7d92e3e2 Debug info: split out complex DIVariable address expressions into a
separate MDNode so they can be uniqued via folding set magic. To conserve
space, DIVariable nodes are still variable-length, with the last two
fields being optional.

No functional change.
http://reviews.llvm.org/D3526

llvm-svn: 212050
2014-06-30 17:17:35 +00:00
Rafael Espindola 6804d450cd Fix another asserting method in the null streamer.
llvm-svn: 211668
2014-06-25 05:37:58 +00:00
David Blaikie 6800e39865 Fix up scoping in a few tests (and delete one that validates unnecessary behavior).
Most of this is just tests that were silently succeeding in spite of
schema changes I made over a year ago. Cleaning them up as they lead to
failures in a change I'm working on/will come soon.

test/DebugInfo/2010-01-19-DbgScope.ll was removed as it tested miscoping
where a DebugLoc described a location not in the current function. The
test case doesn't describe why this is a valid situation and should be
supported, so I'm removing it and shortly going to commit changes that
make this firmly unsupported/assert-fail.

llvm-svn: 211628
2014-06-24 20:10:27 +00:00
David Blaikie de8e12a49a DebugInfo: Fission: Ensure the address pool entries for location lists are emitted.
The address pool was being emitted before location lists. The latter
could add more entries to the pool which would be lost/never emitted.

llvm-svn: 211284
2014-06-19 17:59:14 +00:00
Louis Gerbarg 343f5cdfad Allow X86FastIsel to cope with 64 bit absolute relocations
This patch is a follow up to r211040 & r211052. Rather than bailing out of fast
isel this patch will generate an alternate instruction (movabsq) instead of the
leaq. While this will always have enough room to handle the 64 bit displacment
it is generally over kill for internal symbols (most displacements will be
within 32 bits) but since we have no way of communicating the code model to the
the assmebler in order to avoid flagging an absolute leal/leaq as illegal when
using a symbolic displacement.

llvm-svn: 211130
2014-06-17 23:22:41 +00:00
Louis Gerbarg dcf00251ea Improve comments for r211040
Added comment to clarify why we r211040 choose to bail out of fast isel instead
of generating a more complicated relocation, and fix mislabelled register in the
comments of the asan test case.

llvm-svn: 211052
2014-06-16 20:31:50 +00:00
Louis Gerbarg a5360c4cd8 Fix illegal relocations in X86FastISel
On x86_86  the lea instruction can only use a 32 bit immediate value. When
the code is compiled statically the RIP register is not used, meaning the
immediate is all that can be used for the relocation, which is not sufficient
in the case of targets more than +/- 2GB away. This patch bails out of fast
isel in those cases and reverts to DAG which does the right thing.

Test case included.

llvm-svn: 211040
2014-06-16 17:35:40 +00:00
David Blaikie e847f132f7 DebugInfo: Reference abstract definitions from variables in concrete definitions that preceed their first inline definition.
Rather than relying on abstract variables looked up at the time the
concrete variable is created, look them up at the end of the module to
ensure they're referenced even if they're created after the concrete
definition. This completes/matches the work done in r209677 to handle
this for the subprograms themselves.

llvm-svn: 210946
2014-06-13 22:35:44 +00:00
David Blaikie eb1a27239c DebugInfo: Following up to r209677, refactor local variable emission to delay the choice between emitting the definition attributes or using DW_AT_abstract_definition
This doesn't fix the abstract variable handling yet, but it introduces a
similar delay mechanism as was added for subprograms, causing
DW_AT_location to be reordered to the beginning of the attribute list
for local variables, and fixes all the test fallout for that.

A subsequent commit will remove the abstract variable handling in
DbgVariable and just do the abstract variable lookup at module end to
ensure that abstract variables introduced after their concrete
counterparts are appropriately referenced by the concrete variable.

llvm-svn: 210943
2014-06-13 22:18:23 +00:00
David Blaikie 04ed1d1b68 DebugInfo: Refactor some tests to allow DW_AT_name to not be the first attribute in a local variable.
In an effort to fix concrete variables referencing abstract origins
where the concrete variable preceeds the first inlined usage, the
addition of attributes such as name, file, etc will be delayed until the
end of the module (to wait to see if any inlined instances have
occurred, thus necessitating an abstract definition that the concrete
definition should also reference).

These test cases don't actually need to care about this ordering of
attributes, so update them to be more resilient to such changes coming
in the near future.

llvm-svn: 210940
2014-06-13 21:52:33 +00:00
David Blaikie be315b63e2 test/DebugInfo/X86/dbg-value-isel.s: correct lexical block descriptor to match schema
This silently broke a long time ago when I unified some aspects of the
debug info schema. I'm just cleaning these up if/when they become a
problem.

llvm-svn: 210939
2014-06-13 21:52:28 +00:00
Alp Toker d3d017cf00 Reduce verbiage of lit.local.cfg files
We can just split targets_to_build in one place and make it immutable.

llvm-svn: 210496
2014-06-09 22:42:55 +00:00
Alexey Samsonov 8000e2734e Generate better location ranges for some register-described variables.
Don't terminate location ranges for register-described variables
at the end of machine basic block if this register is never modified
in the function body, except for the prologue and epilogue. Prologue
location is guessed by FrameSetup flags on MachineInstructions, while
epilogue location is deduced from debug locations of instructions
in the basic blocks ending with return instructions.

This patch is mostly targeted to fix non-trivial debug locations for
variables addressed via stack and frame pointers.

It is not really a generic fix. We can still produce poor debug info
for register-described variables if this register *is* modified somewhere
in the function, but in unrelated places. This might be the case for the debug
info in optimized binaries (e.g. for local variables in inlined functions).
LiveDebugVariables pass in CodeGen attempts to fix this problem by adjusting
DBG_VALUE instructions, but this pass is tied to greedy register allocator,
which is used in optimized builds only. Proper fix would likely involve
generalizing LiveDebugVariables to all register allocators. See more discussion
in http://reviews.llvm.org/D3933 review thread.

I'm proceeding with this patch to fix immediate severe problems and
important cases, e.g. fix completely broken debug info with AddressSanitizer
and fix PR19307 (missing debug info for by-value std::string arguments).

llvm-svn: 210492
2014-06-09 21:53:47 +00:00
Alp Toker 5c53639492 Fix typos
llvm-svn: 210401
2014-06-07 21:23:09 +00:00
David Blaikie 3dca59902b DebugInfo: Use the scope of the function declaration, if any, to name a function in DWARF pubnames
This ensures that member functions, for example, are entered into
pubnames with their fully qualified name, rather than inside the global
namespace.

llvm-svn: 210379
2014-06-06 22:29:05 +00:00
David Blaikie 553eb4a880 DebugInfo: pubnames: include file-local (static or anonymous namespace) variables and anonymous namespaces themselves.
Still some issues with name qualification, FIXMEs added to test cases
and fixes will come next.

llvm-svn: 210378
2014-06-06 22:16:56 +00:00
David Blaikie fcf31a73d1 Match the full hex offsets in test/DebugInfo/X86/gnu-public-names.ll
These checks were accidentally skipping the 0x prefix in the hex
offsets, then cunningly ignoring the prefix in the use of those captured
values.

Except in the case of the unit length, where the match was only matching
the leading '0' before the x in the 0x prefix, then matching that
against the length. We can't actually express the length association
here, as the length field in the Compile Unit header does not include
the length field itself, but the length field in the pubnames section
/does/ include the size of the length field in the Compile Unit header -
so the two numbers are actually 4 bytes different. Just skip matching
that.

llvm-svn: 210364
2014-06-06 18:45:14 +00:00
David Blaikie 941644d1bb Remove DWARF3 testing of test/DebugInfo/X86/gnu-public-names.ll
This was added to test that DW_AT_GNU_pubnames used sec_offset in DWARF4
and data4 in DWARF3 and below. Since then we've updated
DW_AT_GNU_pubnames to be a flag, rather than a section offset anyway.

Granted this still differs between DWARF 3 and DWARF 4
(FORM_flag_present versun FORM_flag) but it doesn't seem worthwhile
testing that codepath again here. It's covered adequately in many other
test cases.

And while I'm here, don't hardcode the byte size of the compile unit -
it's not relevant to this test and just makes it brittle if/when
anything changes in the way this CU is emitted.

llvm-svn: 210362
2014-06-06 18:22:04 +00:00
Alp Toker da0c7933cf Fix typos
llvm-svn: 209982
2014-05-31 21:26:28 +00:00
David Blaikie 482097d098 DebugInfo: Create abstract function definitions even when concrete definitions preceed inline definitions.
After much puppetry, here's the major piece of the work to ensure that
even when a concrete definition preceeds all inline definitions, an
abstract definition is still created and referenced from both concrete
and inline definitions.

Variables are still broken in this case (see comment in
dbg-value-inlined-parameter.ll test case) and will be addressed in
follow up work.

llvm-svn: 209677
2014-05-27 18:37:55 +00:00
David Blaikie 3c2fff3fe6 DebugInfo: Lazily construct subprogram definition DIEs.
A further step to correctly emitting concrete out of line definitions
preceeding inlined instances of the same program.

To do this, emission of subprograms must be delayed until required since
we don't know which (abstract only (if there's no out of line
definition), concrete only (if there are no inlined instances), or both)
DIEs are required at the start of the module.

To reduce the test churn in the following commit that actually fixes the
bug, this commit introduces the lazy DIE construction and cleans up test
cases that are impacted by the changes in the resulting DIE ordering.

llvm-svn: 209675
2014-05-27 18:37:48 +00:00
David Blaikie f7221adb8e DebugInfo: Lazily attach definition attributes to definitions.
This is a precursor to fixing inlined debug info where the concrete,
out-of-line definition may preceed any inlined usage. To cope with this,
the attributes that may appear on the concrete definition or the
abstract definition are delayed until the end of the module. Then, if an
abstract definition was created, it is referenced (and no other
attributes are added to the out-of-line definition), otherwise the
attributes are added directly to the out-of-line definition.

In a couple of cases this causes not just reordering of attributes, but
reordering of types. When the creation of the attribute is delayed, if
that creation would create a type (such as for a DW_AT_type attribute)
then other top level DIEs may've been constructed during the delay,
causing the referenced type to be created and added after those
intervening DIEs. In the extreme case, in cross-cu-inlining.ll, this
actually causes the DW_TAG_basic_type for "int" to move from one CU to
another.

llvm-svn: 209674
2014-05-27 18:37:43 +00:00
David Blaikie 66c3077470 DebugInfo: Fix argument ordering in test by adding argument numbering.
This old test didn't have the argument numbering that's now squirelled
away in the high bits of the line number in the DW_TAG_arg_variable
metadata.

Add the numbering and update the test to ensure arguments are in-order.

llvm-svn: 209669
2014-05-27 17:57:14 +00:00
David Blaikie 69d3406a2d Streamline test case by avoiding a temporary file and piping llc output straight to llvm-dwarfdump
We still do temporary files in many cases, just updating this particular
one because I was debugging it and made this change while doing so.

llvm-svn: 209601
2014-05-25 15:38:52 +00:00
David Blaikie 2f75351c02 DebugInfo: Generalize some tests to handle variations in attribute ordering.
In an effort to fix inlined debug info in situations where the out of
line definition of a function preceeds any inlined usage, the order in
which some attributes are added to subprogram DIEs may change. (in
essence, definition-necessary attributes like DW_AT_low_pc/high_pc will
be added immediately, but the names, types, and other features will be
delayed to module end where they may either be added to the subprogram
DIE or instead reference an abstract definition for those values)

These tests can be generalized to be resilient to this change. 5 or so
tests actually have to be incompatibly changed to cope with this
reordering and will go along with the change that affects the order.

llvm-svn: 209554
2014-05-23 21:11:46 +00:00
David Blaikie 71ed20f671 DebugInfo: Generalize a test case to not depend on abbreviation numbering.
It's an unnecessary detail for this test and just gets in the way when
making unrelated changes to the output in this test.

llvm-svn: 209553
2014-05-23 21:07:01 +00:00
David Blaikie 2da282b860 Revert "DebugInfo: Don't put fission type units in comdat sections."
This reverts commit r208930, r208933, and r208975.

It seems not all fission consumers are ready to handle this behavior.
Reverting until tools are brought up to spec.

llvm-svn: 209338
2014-05-21 23:27:41 +00:00
David Blaikie 825bdd2fc6 DebugInfo: Ensure concrete out of line variables from inlined functions reference their abstract origins.
llvm-svn: 209327
2014-05-21 22:41:17 +00:00
David Blaikie ce7a1bd038 DebugInfo: Simplify subprogram declaration creation/references and accidentally refix PR11300.
Also simplifies the linkage name handling a little too.

llvm-svn: 209311
2014-05-21 18:04:33 +00:00
Eric Christopher a6342c581e Add a comment here.
llvm-svn: 209262
2014-05-21 00:02:50 +00:00
Eric Christopher 12a7155f60 Move this test to the backend from the frontend.
llvm-svn: 209259
2014-05-20 23:59:54 +00:00
Eric Christopher 2feed5fd68 Move the function and data section flags into the options struct and
make the functions to set them non-static.
Move and rename the llvm specific backend options to avoid conflicting
with the clang option.

Paired with a backend commit to update.

llvm-svn: 209238
2014-05-20 21:25:34 +00:00
David Blaikie 424b59b1ce DebugInfo: Assume all subprogram DIEs have been created before any abstract subprograms are constructed.
Since we visit the whole list of subprograms for each CU at module
start, this is clearly true - don't test for the case, just assert it.

A few old test cases seemed to have incomplete subprogram lists, but any
attempt to reproduce them shows full subprogram lists that even include
entities that have been completely inlined and the out of line
definition removed.

llvm-svn: 209178
2014-05-19 23:16:19 +00:00
David Blaikie 973141a035 DebugInfo: Don't include DW_AT_inline on each abstract definition multiple times.
When I refactored this in r208636 I accidentally caused this to be added
multiple times to each abstract subprogram (not accounting for the
deduplicating effect of the InlinedSubprogramDIEs set).

This got better in r208798 when the abstract definitions got the
attribute added to them at construction time, but still had the
redundant copies introduced in r208636.

This commit removes those excess DW_AT_inlines and relies solely on the
insertion in r208798.

llvm-svn: 209166
2014-05-19 22:07:16 +00:00
David Blaikie 48b056bab0 DebugInfo: Fix missing inlined_subroutines caused by r208748.
The check in DwarfDebug::constructScopeDIE was meant to consider inlined
subroutines as any non-top-level scope that was a subprogram. Instead of
checking "not top level scope" it was checking if the /subprogram's/
scope was non-top-level.

Fix this and beef up a test case to demonstrate some of the missing
inlined_subroutines are no longer missing.

In the course of fixing this I also found that r208748 (with this fix)
found one /extra/ inlined_subroutine in concrete_out_of_line.ll due to
two inlined_subroutines having the same inlinedAt location. The previous
implementation was collapsing these into a single inlined subroutine.

I'm not sure what the original code was that created this .ll file so
I'm not sure if this actually happens in practice today. Since we
deliberately include column information to disambiguate two calls on the
same line, that may've addressed this bug in the frontend, but it's good
to know that workaround isn't necessary for this particular case
anymore.

llvm-svn: 209165
2014-05-19 21:54:31 +00:00
David Blaikie 825f487b68 DebugInfo: Assume the CU's Subprogram list only contains definitions.
DIBuilder maintains this invariant and the current DwarfDebug code could
end up doing weird things if it contained declarations (such as putting
the definition DIE inside a CU that contained the declaration - this
doesn't seem like a good idea, so rather than adding logic to handle
this case we'll just ban in for now & cross that bridge if we come to
it later).

llvm-svn: 209004
2014-05-16 18:26:53 +00:00