Commit Graph

38 Commits

Author SHA1 Message Date
Puyan Lotfi 43e94b15ea Followup on Proposal to move MIR physical register namespace to '$' sigil.
Discussed here:

http://lists.llvm.org/pipermail/llvm-dev/2018-January/120320.html

In preparation for adding support for named vregs we are changing the sigil for
physical registers in MIR to '$' from '%'. This will prevent name clashes of
named physical register with named vregs.

llvm-svn: 323922
2018-01-31 22:04:26 +00:00
Jonas Devlieghere 6f24c8778c [DebugInfo] Unify dumping of address ranges
Summary:
This patch unifies the printing of address ranges as [0x0, 0x1).

rdar://34822059

Reviewers: aprantl, dblaikie

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D42056

llvm-svn: 322543
2018-01-16 11:17:57 +00:00
Francis Visoiu Mistrih 9d7bb0cb40 [CodeGen] Print register names in lowercase in both MIR and debug output
As part of the unification of the debug format and the MIR format,
always print registers as lowercase.

* Only debug printing is affected. It now follows MIR.

Differential Revision: https://reviews.llvm.org/D40417

llvm-svn: 319187
2017-11-28 17:15:09 +00:00
Adrian Prantl 7bc1b28291 llvm-dwarfdump: Replace -debug-dump=sect option with individual options.
As discussed on llvm-dev in
http://lists.llvm.org/pipermail/llvm-dev/2017-September/117301.html
this changes the command line interface of llvm-dwarfdump to match the
one used by the dwarfdump utility shipping on macOS. In addition to
being shorter to type this format also has the advantage of allowing
more than one section to be specified at the same time.

In a nutshell, with this change

  $ llvm-dwarfdump --debug-dump=info
  $ llvm-dwarfdump --debug-dump=apple-objc

becomes

  $ dwarfdump --debug-info --apple-objc

Differential Revision: https://reviews.llvm.org/D37714

llvm-svn: 312970
2017-09-11 22:59:45 +00:00
Reid Kleckner a058736c9c [dwarfdump] Pretty print location expressions and location lists
Summary:
Based on Fred's patch here: https://reviews.llvm.org/D6771

I can't seem to commandeer the old review, so I'm creating a new one.

With that change the locations exrpessions are pretty printed inline in the
DIE tree. The output looks like this for debug_loc entries:

    DW_AT_location [DW_FORM_data4]        (0x00000000
       0x0000000000000001 - 0x000000000000000b: DW_OP_consts +3
       0x000000000000000b - 0x0000000000000012: DW_OP_consts +7
       0x0000000000000012 - 0x000000000000001b: DW_OP_reg0 RAX, DW_OP_piece 0x4
       0x000000000000001b - 0x0000000000000024: DW_OP_breg5 RDI+0)

And like this for debug_loc.dwo entries:
    DW_AT_location [DW_FORM_sec_offset]   (0x00000000
      Addr idx 2 (w/ length 190): DW_OP_consts +0, DW_OP_stack_value
      Addr idx 3 (w/ length 23): DW_OP_reg0 RAX, DW_OP_piece 0x4)

Simple locations without ranges are printed inline:

   DW_AT_location [DW_FORM_block1]       (DW_OP_reg4 RSI, DW_OP_piece 0x4, DW_OP_bit_piece 0x20 0x0)

The debug_loc(.dwo) dumping in changed accordingly to factor the code.

Reviewers: dblaikie, aprantl, friss

Subscribers: mgorny, javed.absar, hiraditya, llvm-commits, JDevlieghere

Differential Revision: https://reviews.llvm.org/D37123

llvm-svn: 312042
2017-08-29 21:41:21 +00:00
Adrian Prantl 032d2381bf Remove PrologEpilogInserter's usage of DBG_VALUE's offset field
In the last half-dozen commits to LLVM I removed code that became dead
after removing the offset parameter from llvm.dbg.value gradually
proceeding from IR towards the backend. Before I can move on to
DwarfDebug and friends there is one last side-called offset I need to
remove:  This patch modifies PrologEpilogInserter's use of the
DBG_VALUE's offset argument to use a DIExpression instead. Because the
PrologEpilogInserter runs at the Machine level I had to play a little
trick with a named llvm.dbg.mir node to get the DIExpressions to print
in MIR dumps (which print the llvm::Module followed by the
MachineFunction dump).

I also had to add rudimentary DwarfExpression support to CodeView and
as a side-effect also fixed a bug (CodeViewDebug::collectVariableInfo
was supposed to give up on variables with complex DIExpressions, but
would fail to do so for fragments, which are also modeled as
DIExpressions).

With this last holdover removed we will have only one canonical way of
representing offsets to debug locations which will simplify the code
in DwarfDebug (and future versions of CodeViewDebug once it starts
handling more complex expressions) and make it easier to reason about.

This patch is NFC-ish: All test case changes are for assembler
comments and the binary output does not change.

rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D36125

llvm-svn: 309751
2017-08-01 21:45:24 +00:00
Adrian Prantl 56619fa7e9 Debug Info: Also check the DWARF output in assembler-only test cases
This will prevent me from introducing a regression in my next commit.

llvm-svn: 309623
2017-07-31 20:48:52 +00:00
Adrian Prantl de1a8b4efb Print complete DIExpressions in the assembler output DEBUG_VALUE comments.
The previous code was complex, incorrect, and couldn't print everything.

llvm-svn: 301333
2017-04-25 17:22:09 +00:00
Adrian Prantl 75819aedf6 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446
2016-04-15 15:57:41 +00:00
Adrian Prantl b8089516a5 testcase gardening: update the emissionKind enum to the new syntax. (NFC)
llvm-svn: 265081
2016-04-01 00:16:49 +00:00
Reid Kleckner f6f04f8fc8 Consider regmasks when computing register-based DBG_VALUE live ranges
Now register parameters that aren't saved to the stack or CSRs are
considered dead after the first call. Previously the debugger would show
whatever was in the register.

Fixes PR26589

Reviewers: aprantl

Differential Revision: http://reviews.llvm.org/D17211

llvm-svn: 264429
2016-03-25 17:54:46 +00:00
Keno Fischer 00cbf9a69a Clean up the processing of dbg.value in various places
Summary:
First up is instcombine, where in the dbg.declare -> dbg.value conversion,
the llvm.dbg.value needs to be called on the actual loaded value, rather
than the address (since the whole point of this transformation is to be
able to get rid of the alloca). Further, now that that's cleaned up, we
can remove a hack in the backend, that would add an implicit OP_deref if
the argument to dbg.value was an alloca. This stems from before the
existence of DIExpression and is no longer necessary since the deref can
be expressed explicitly.

Now, in order to make sure that the tests pass with this change, we need to
correct the printing of DEBUG_VALUE comments to take into account the
expression, which wasn't taken into account before.

Unfortunately, for both these changes, there were a number of incorrect
test cases (mostly the wrong number of DW_OP_derefs, but also a couple
where the test itself was broken more badly). aprantl and I have gone
through and adjusted these test case in order to make them pass with
these fixes and in some cases to make sure they're actually testing
what they are meant to test.

Reviewers: aprantl

Subscribers: dsanders

Differential Revision: http://reviews.llvm.org/D14186

llvm-svn: 256077
2015-12-19 02:02:44 +00:00
Dan Gohman 6c1b0b9a88 Update DebugInfo tests for the change in DEBUG_VALUE output in r253338.
llvm-svn: 253340
2015-11-17 16:15:11 +00:00
Peter Collingbourne d4bff30370 DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.

For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.

This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.

Since this is an IR change, a bitcode upgrade has been provided.

Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.

Differential Revision: http://reviews.llvm.org/D14265

llvm-svn: 252219
2015-11-05 22:03:56 +00:00
Duncan P. N. Exon Smith 814b8e91c7 DI: Require subprogram definitions to be distinct
As a follow-up to r246098, require `DISubprogram` definitions
(`isDefinition: true`) to be 'distinct'.  Specifically, add an assembler
check, a verifier check, and bitcode upgrading logic to combat testcase
bitrot after the `DIBuilder` change.

While working on the testcases, I realized that
test/Linker/subprogram-linkonce-weak-odr.ll isn't relevant anymore.  Its
purpose was to check for a corner case in PR22792 where two subprogram
definitions match exactly and share the same metadata node.  The new
verifier check, requiring that subprogram definitions are 'distinct',
precludes that possibility.

I updated almost all the IR with the following script:

    git grep -l -E -e '= !DISubprogram\(.* isDefinition: true' |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's/= \(!DISubprogram(.*, isDefinition: true\)/= distinct \1/'

Likely some variant of would work for out-of-tree testcases.

llvm-svn: 246327
2015-08-28 20:26:49 +00:00
Duncan P. N. Exon Smith 55ca964e94 DI: Disallow uniquable DICompileUnits
Since r241097, `DIBuilder` has only created distinct `DICompileUnit`s.
The backend is liable to start relying on that (if it hasn't already),
so make uniquable `DICompileUnit`s illegal and automatically upgrade old
bitcode.  This is a nice cleanup, since we can remove an unnecessary
`DenseSet` (and the associated uniquing info) from `LLVMContextImpl`.

Almost all the testcases were updated with this script:

    git grep -e '= !DICompileUnit' -l -- test |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's,= !DICompileUnit,= distinct !DICompileUnit,'

I imagine something similar should work for out-of-tree testcases.

llvm-svn: 243885
2015-08-03 17:26:41 +00:00
Duncan P. N. Exon Smith ed013cd221 DI: Remove DW_TAG_arg_variable and DW_TAG_auto_variable
Remove the fake `DW_TAG_auto_variable` and `DW_TAG_arg_variable` tags,
using `DW_TAG_variable` in their place Stop exposing the `tag:` field at
all in the assembly format for `DILocalVariable`.

Most of the testcase updates were generated by the following sed script:

    find test/ -name "*.ll" -o -name "*.mir" |
    xargs grep -l 'DILocalVariable' |
    xargs sed -i '' \
      -e 's/tag: DW_TAG_arg_variable, //' \
      -e 's/tag: DW_TAG_auto_variable, //'

There were only a handful of tests in `test/Assembly` that I needed to
update by hand.

(Note: a follow-up could change `DILocalVariable::DILocalVariable()` to
set the tag to `DW_TAG_formal_parameter` instead of `DW_TAG_variable`
(as appropriate), instead of having that logic magically in the backend
in `DbgVariable`.  I've added a FIXME to that effect.)

llvm-svn: 243774
2015-07-31 18:58:39 +00:00
Duncan P. N. Exon Smith a9308c49ef IR: Give 'DI' prefix to debug info metadata
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`.  The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.

Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one.  It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs.  YMMV of
course.

Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py.  I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three.  It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).

Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.

llvm-svn: 236120
2015-04-29 16:38:44 +00:00
Duncan P. N. Exon Smith 48b3503c16 DebugInfo: Add missing !dbg attachments to intrinsics
Add missing `!dbg` attachments to `@llvm.dbg.*` intrinsics.  I updated
these using a script (add-dbg-to-intrinsics.sh) that I'll attach to
PR22778 for posterity.

llvm-svn: 235040
2015-04-15 21:04:10 +00:00
Rafael Espindola 07c03d316d Use the existing begin and end symbol for debug info.
llvm-svn: 231338
2015-03-05 02:05:42 +00:00
Rafael Espindola 310e4b592f Use the vanilla func_end symbol for .size.
No need to create yet another temp symbol.

llvm-svn: 231198
2015-03-04 01:35:23 +00:00
Duncan P. N. Exon Smith e274180f0e DebugInfo: Move new hierarchy into place
Move the specialized metadata nodes for the new debug info hierarchy
into place, finishing off PR22464.  I've done bootstraps (and all that)
and I'm confident this commit is NFC as far as DWARF output is
concerned.  Let me know if I'm wrong :).

The code changes are fairly mechanical:

  - Bumped the "Debug Info Version".
  - `DIBuilder` now creates the appropriate subclass of `MDNode`.
  - Subclasses of DIDescriptor now expect to hold their "MD"
    counterparts (e.g., `DIBasicType` expects `MDBasicType`).
  - Deleted a ton of dead code in `AsmWriter.cpp` and `DebugInfo.cpp`
    for printing comments.
  - Big update to LangRef to describe the nodes in the new hierarchy.
    Feel free to make it better.

Testcase changes are enormous.  There's an accompanying clang commit on
its way.

If you have out-of-tree debug info testcases, I just broke your build.

  - `upgrade-specialized-nodes.sh` is attached to PR22564.  I used it to
    update all the IR testcases.
  - Unfortunately I failed to find way to script the updates to CHECK
    lines, so I updated all of these by hand.  This was fairly painful,
    since the old CHECKs are difficult to reason about.  That's one of
    the benefits of the new hierarchy.

This work isn't quite finished, BTW.  The `DIDescriptor` subclasses are
almost empty wrappers, but not quite: they still have loose casting
checks (see the `RETURN_FROM_RAW()` macro).  Once they're completely
gutted, I'll rename the "MD" classes to "DI" and kill the wrappers.  I
also expect to make a few schema changes now that it's easier to reason
about everything.

llvm-svn: 231082
2015-03-03 17:24:31 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +00:00
Duncan P. N. Exon Smith 9885469922 IR: Move MDLocation into place
This commit moves `MDLocation`, finishing off PR21433.  There's an
accompanying clang commit for frontend testcases.  I'll attach the
testcase upgrade script I used to PR21433 to help out-of-tree
frontends/backends.

This changes the schema for `DebugLoc` and `DILocation` from:

    !{i32 3, i32 7, !7, !8}

to:

    !MDLocation(line: 3, column: 7, scope: !7, inlinedAt: !8)

Note that empty fields (line/column: 0 and inlinedAt: null) don't get
printed by the assembly writer.

llvm-svn: 226048
2015-01-14 22:27:36 +00:00
Adrian Prantl 092d9489ed Debug Info: Move the complex expression handling (=the remainder) of
emitDebugLocValue() into DwarfExpression.

Ought to be NFC, but it actually uncovered a bug in the debug-loc-asan.ll
testcase. The testcase checks that the address of variable "y" is stored
at [RSP+16], which also lines up with the comment.
It also check(ed) that the *value* of "y" is stored in RDI before that,
but that is actually incorrect, since RDI is the very value that is
stored in [RSP+16]. Here's the assembler output:

	movb	2147450880(%rcx), %r8b
	#DEBUG_VALUE: bar:y <- RDI
	cmpb	$0, %r8b
	movq	%rax, 32(%rsp)          # 8-byte Spill
	movq	%rsi, 24(%rsp)          # 8-byte Spill
	movq	%rdi, 16(%rsp)          # 8-byte Spill
.Ltmp3:
	#DEBUG_VALUE: bar:y <- [RSP+16]

Fixed the comment to spell out the correct register and the check to
expect an address rather than a value.

Note that the range that is emitted for the RDI location was and is still
wrong, it claims to begin at the function prologue, but really it should
start where RDI is first assigned.

llvm-svn: 225851
2015-01-13 23:39:11 +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
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
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
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
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
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