Commit Graph

358 Commits

Author SHA1 Message Date
Teresa Johnson 9b4b8c8d7b Enable stripping of multiple DILocation on !llvm.loop metadata
Summary:
I found that stripDebugInfo was still leaving significant amounts of
debug info due to !llvm.loop that contained DILocation after stripping.
The support for stripping debug info on !llvm.loop added in r293377 only
removes a single DILocation. Enhance that to remove all DILocation from
!llvm.loop.

Reviewers: hfinkel, aprantl, dsanders

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31117

llvm-svn: 298213
2017-03-19 13:54:57 +00:00
Dehao Chen 0944a8c2ec Change debug-info-for-profiling from a TargetOption to a function attribute.
Summary: LTO requires the debug-info-for-profiling to be a function attribute.

Reviewers: echristo, mehdi_amini, dblaikie, probinson, aprantl

Reviewed By: mehdi_amini, dblaikie, aprantl

Subscribers: aprantl, probinson, ahatanak, llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D29203

llvm-svn: 293833
2017-02-01 22:45:09 +00:00
Daniel Sanders b96a945bf5 stripDebugInfo() should remove DILocation's found in !llvm.loop metadata
Summary:
Patch by Michele Scandale
(with a small tweak to 'CHECK-NOT' the last DILocation in the test)

Subscribers: bogner, llvm-commits

Differential Revision: https://reviews.llvm.org/D27980

llvm-svn: 293377
2017-01-28 11:22:05 +00:00
Adrian Prantl bceaaa9643 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades and a change
to the Bitcode record for DIGlobalVariable, that makes upgrading the
old format unambiguous also for variables without DIExpressions.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 290153
2016-12-20 02:09:43 +00:00
Adrian Prantl 73ec065604 Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289920 (again).
I forgot to implement a Bitcode upgrade for the case where a DIGlobalVariable
has not DIExpression. Unfortunately it is not possible to safely upgrade
these variables without adding a flag to the bitcode record indicating which
version they are.
My plan of record is to roll the planned follow-up patch that adds a
unit: field to DIGlobalVariable into this patch before recomitting.
This way we only need one Bitcode upgrade for both changes (with a
version flag in the bitcode record to safely distinguish the record
formats).

Sorry for the churn!

llvm-svn: 289982
2016-12-16 19:39:01 +00:00
Adrian Prantl 74a835cda0 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289920
2016-12-16 04:25:54 +00:00
Adrian Prantl 03c6d31a3b Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289902 while investigating bot berakage.

llvm-svn: 289906
2016-12-16 01:00:30 +00:00
Adrian Prantl ce13935776 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289902
2016-12-16 00:36:43 +00:00
Michael Ilseman e542804343 Add -strip-nonlinetable-debuginfo capability
This adds a new function to DebugInfo.cpp that takes an llvm::Module
as input and removes all debug info metadata that is not directly
needed for line tables, thus effectively stripping all type and
variable information from the module.

The primary motivation for this feature was the bitcode work flow
(cf. http://lists.llvm.org/pipermail/llvm-dev/2016-June/100643.html
for more background). This is not wired up yet, but will be in
subsequent patches.  For testing, the new functionality is exposed to
opt with a -strip-nonlinetable-debuginfo option.

The secondary use-case (and one that works right now!) is as a
reduction pass in bugpoint. I added two new bugpoint options
(-disable-strip-debuginfo and -disable-strip-debug-types) to control
the new features. By default it will first attempt to remove all debug
information, then only the type info, and then proceed to hack at any
remaining MDNodes.

Thanks to Adrian Prantl for stewarding this patch!

llvm-svn: 285094
2016-10-25 18:44:13 +00:00
Davide Italiano 84bd58e915 [opt] Strip coverage if debug info is not present.
If -coverage is passed, but -g is not, clang populates the PassManager
pipeline with StripSymbols(debugOnly = true).
The stripSymbol pass therefore scans the list of named metadata,
drops !llvm.dbg.cu, but leaves !llvm.gcov and !0 (the compileUnit MD)
around. The verifier runs, and finds out that there's a CU not listed
in !llvm.dbg.cu (as it was previously dropped) -> crash.
When we strip debug info, so, check if there's coverage data,
and strip it as well, in order to avoid pending metadata left around.

Differential Revision:  https://reviews.llvm.org/D25689

llvm-svn: 284418
2016-10-17 20:05:35 +00:00
Adrian Prantl 3bfe1093df Teach llvm::StripDebugInfo() about global variable !dbg attachments.
This is a regression introduced by the global variable ownership
reversal performed in r281284.

rdar://problem/28448075

llvm-svn: 283784
2016-10-10 17:53:33 +00:00
Michael Ilseman 6d6b4d87a3 Revert "Add -strip-nonlinetable-debuginfo capability"
This reverts commit r283473.

Reverted until review is completed.

llvm-svn: 283478
2016-10-06 18:30:26 +00:00
Michael Ilseman d0a4db7632 Add -strip-nonlinetable-debuginfo capability
This adds a new function to DebugInfo.cpp that takes an llvm::Module
as input and removes all debug info metadata that is not directly
needed for line tables, thus effectively stripping all type and
variable information from the module.

The primary motivation for this feature was the bitcode work flow
(cf. http://lists.llvm.org/pipermail/llvm-dev/2016-June/100643.html
for more background). This is not wired up yet, but will be in
subsequent patches.  For testing, the new functionality is exposed to
opt with a -strip-nonlinetable-debuginfo option.

The secondary use-case (and one that works right now!) is as a
reduction pass in bugpoint. I added two new bugpoint options
(-disable-strip-debuginfo and -disable-strip-debug-types) to control
the new features. By default it will first attempt to remove all debug
information, then only the type info, and then proceed to hack at any
remaining MDNodes.

llvm-svn: 283473
2016-10-06 17:58:38 +00:00
Mehdi Amini db8dd5515d StripDebugInfo: uses isa<DbgInfoIntrinsic> instead of matching against llvm.dbg.* (NFC)
Suggested by Adrian. This is NFC right now but is more clean and
robust against future potential new debug info intrinsics.

From: mehdi_amini <mehdi_amini@91177308-0d34-0410-b5e6-96231b3b80d8>
llvm-svn: 269540
2016-05-14 04:58:35 +00:00
Mehdi Amini 2f8a5f3f44 Revert "StripDebugInfo: uses isa<DbgInfoIntrinsic> instead of matching against llvm.dbg.* (NFC)"
This reverts commit r269537, was not ready to be commited and went through by mistake

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 269539
2016-05-14 04:42:51 +00:00
Mehdi Amini ac85189998 StripDebugInfo: uses isa<DbgInfoIntrinsic> instead of matching against llvm.dbg.* (NFC)
Suggested by Adrian. This is NFC right now but is more clean and
robust against future potential new debug info intrinsics.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 269537
2016-05-14 04:41:21 +00:00
Mehdi Amini bbedb1495c Fix stripDebugInfo: was modifying "DebugLoc" attached to the intrinsic after deleting it.
Fix MSAN build.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 268849
2016-05-07 05:07:47 +00:00
Mehdi Amini 581f0e1451 Refactor stripDebugInfo(Function) to handle intrinsic
This moves the code that handles stripping debug info intrinsic from
 StripDebugInfo(Module) to StripDebugInfo(Function). The latter is
already walking every instructions so it makes sense to do it at the
same time.
This makes also stripDebugInfo(Function) as an API more useful: it
is really dropping every debug info in the Function.
Finally the existing code is trigerring an assertion when the Module
is not fully materialized.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 268847
2016-05-07 04:10:52 +00:00
Vitaly Buka 49bbbd8e7a Revert r268832 "Refactor stripDebugInfo(Function) to handle intrinsic"
It breaks many bots

llvm-svn: 268837
2016-05-07 02:10:59 +00:00
Mehdi Amini 6eef08138e Refactor stripDebugInfo(Function) to handle intrinsic
This moves the code that handles stripping debug info intrinsic from
 StripDebugInfo(Module) to StripDebugInfo(Function). The latter is
already walking every instructions so it makes sense to do it at the
same time.
This makes also stripDebugInfo(Function) as an API more useful: it
is really dropping every debug info in the Function.
Finally the existing code is trigerring an assertion when the Module
is not fully materialized.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 268832
2016-05-07 01:42:36 +00:00
Duncan P. N. Exon Smith a59d3e5af8 DebugInfo: Remove MDString-based type references
Eliminate DITypeIdentifierMap and make DITypeRef a thin wrapper around
DIType*.  It is no longer legal to refer to a DICompositeType by its
'identifier:', and DIBuilder no longer retains all types with an
'identifier:' automatically.

Aside from the bitcode upgrade, this is mainly removing logic to resolve
an MDString-based reference to an actualy DIType.  The commits leading
up to this have made the implicit type map in DICompileUnit's
'retainedTypes:' field superfluous.

This does not remove DITypeRef, DIScopeRef, DINodeRef, and
DITypeRefArray, or stop using them in DI-related metadata.  Although as
of this commit they aren't serving a useful purpose, there are patchces
under review to reuse them for CodeView support.

The tests in LLVM were updated with deref-typerefs.sh, which is attached
to the thread "[RFC] Lazy-loading of debug info metadata":

  http://lists.llvm.org/pipermail/llvm-dev/2016-April/098318.html

llvm-svn: 267296
2016-04-23 21:08:00 +00:00
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +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 5992a72b4d Support the Nodebug emission kind for DICompileUnits.
Sample-based profiling and optimization remarks currently remove
DICompileUnits from llvm.dbg.cu to suppress the emission of debug info
from them. This is somewhat of a hack and only borderline legal IR.

This patch uses the recently introduced NoDebug emission kind in
DICompileUnit to achieve the same result without breaking the Verifier.
A nice side-effect of this change is that it is now possible to combine
NoDebug and regular compile units under LTO.

http://reviews.llvm.org/D18808
<rdar://problem/25427165>

llvm-svn: 265861
2016-04-08 22:43:03 +00:00
Pete Cooper adebb9379a Remove llvm::getDISubprogram in favor of Function::getSubprogram
llvm::getDISubprogram walks the instructions in a function, looking for one in the scope of the current function, so that it can find the !dbg entry for the subprogram itself.

Now that !dbg is attached to functions, this should not be necessary. This patch changes all uses to just query the subprogram directly on the function.

Ideally this should be NFC, but in reality its possible that a function:

has no !dbg (in which case there's likely a bug somewhere in an opt pass), or
that none of the instructions had a scope referencing the function, so we used to not find the !dbg on the function but now we will

Reviewed by Duncan Exon Smith.

Differential Revision: http://reviews.llvm.org/D18074

llvm-svn: 263184
2016-03-11 02:14:16 +00:00
Benjamin Kramer 391be792f2 One more batch of self-containing headers.
llvm-svn: 258974
2016-01-27 19:29:56 +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 52888a6738 IR: Remove implicit iterator conversions from lib/IR, NFC
Stop converting implicitly between iterators and pointers/references in
lib/IR.  For convenience, I've added a `getIterator()` accessor to
`ilist_node` so that callers don't need to know how to spell the
iterator class (i.e., they can use `X.getIterator()` instead of
`Function::iterator(X)`).

I'll eventually disallow these implicit conversions entirely, but
there's a lot of code, so it doesn't make sense to do it all in one
patch.  One library or so at a time.

Why?  To root out cases of `getNextNode()` and `getPrevNode()` being
used in iterator logic.  The design of `ilist` makes that invalid when
the current node could be at the back of the list, but it happens to
"work" right now because of a bug where those functions never return
`nullptr` if you're using a half-node sentinel.  Before I can fix the
function, I have to remove uses of it that rely on it misbehaving.
(Maybe the function should just be deleted anyway?  But I don't want
deleting it -- potentially a huge project -- to block fixing
ilist/iplist.)

llvm-svn: 249782
2015-10-08 23:49:46 +00:00
Duncan P. N. Exon Smith 260fa8a75b DI: Simplify DebugInfoFinder::processType(), NFC
Handle `DISubroutineType` up-front rather than as part of a branch for
`DICompositeTypeBase`.  The only shared code path was looking through
the base type, but `DISubroutineType` can never have a base type.

This also removes the last use of `DICompositeTypeBase`, since we can
strengthen the cast to `DICompositeType`.

llvm-svn: 243159
2015-07-24 20:56:10 +00:00
Duncan P. N. Exon Smith 3c5a56b13c DI: Remove dead code: getDICompositeType()
llvm-svn: 243158
2015-07-24 20:46:46 +00:00
Duncan P. N. Exon Smith 2ecfb1e269 DI: Strengthen some dyn_casts to DIDerivedType, NFC
The surrounding code proves in both cases that these must be
`DIDerivedType` if they're `DIDerivedTypeBase`, so strengthen the
`dyn_cast`s to the more specific type.

llvm-svn: 243143
2015-07-24 19:17:20 +00:00
Adrian Prantl ab1243fe6c Add a DIModule metadata node to the IR.
It is meant to be used to record modules @imported by the current
compile unit, so a debugger an import the same modules to replicate this
environment before dropping into the expression evaluator.

DIModule is a sibling to DINamespace and behaves quite similarly.
In addition to the name of the module it also records the module
configuration details that are necessary to uniquely identify the module.
This includes the configuration macros (e.g., -DNDEBUG), the include path
where the module.map file is to be found, and the isysroot.

The idea is that the backend will turn this into a DW_TAG_module.

http://reviews.llvm.org/D9614
rdar://problem/20965932

llvm-svn: 241017
2015-06-29 23:03:47 +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 aa861aa483 DebugInfo: Remove DIArray and DITypeArray typedefs
Remove the `DIArray` and `DITypeArray` typedefs, preferring the
underlying types (`DebugNodeArray` and `MDTypeRefArray`, respectively).

llvm-svn: 235413
2015-04-21 20:07:38 +00:00
Duncan P. N. Exon Smith ed557b55ee DebugInfo: Remove DIDescriptor from the DebugInfo API
Stop using `DIDescriptor` and its subclasses in the `DebugInfoFinder`
API, as well as the rest of the API hanging around in `DebugInfo.h`.

llvm-svn: 235240
2015-04-17 23:20:10 +00:00
Duncan P. N. Exon Smith b0b0e4958b DebugInfo: DIRef<> => TypedDebugNodeRef<>
Delete `DIRef<>`, and replace the remaining uses of it with
`TypedDebugNodeRef<>`.  To minimize code churn, I've added typedefs from
`MDTypeRef` to `DITypeRef` (etc.).

llvm-svn: 235071
2015-04-16 02:24:01 +00:00
Duncan P. N. Exon Smith f15c6f8032 DebugInfo: Gut DIDescriptor
PR23080 is almost finished.  With this commit, there's no consequential
API in `DIDescriptor` and its subclasses.  What's left?

  - Default-constructed to `nullptr`.
  - Handy `const_cast<>` (constructed from `const`, but accessors are
    non-`const`).

I think the safe way to catch those is to delete the classes and fix
compile errors.  That'll be my next step, after I delete the `DITypeRef`
(etc.) wrapper around `MDTypeRef`.

llvm-svn: 235069
2015-04-16 01:53:33 +00:00
Duncan P. N. Exon Smith b273d06b63 DebugInfo: Gut DIScope, DIEnumerator and DISubrange
The only class the still has API left is `DIDescriptor` itself.

llvm-svn: 235067
2015-04-16 01:37:00 +00:00
Duncan P. N. Exon Smith b105564015 DebugInfo: Gut DIType and subclasses
Continuing PR23080, gut `DIType` and its various subclasses, leaving
behind thin wrappers around the pointer types in the new debug info
hierarchy.

llvm-svn: 235064
2015-04-16 01:01:28 +00:00
Duncan P. N. Exon Smith 35ef22cf53 DebugInfo: Gut DICompileUnit and DIFile
Continuing gutting `DIDescriptor` subclasses; this edition,
`DICompileUnit` and `DIFile`.  In the name of PR23080.

llvm-svn: 235055
2015-04-15 23:19:27 +00:00
Duncan P. N. Exon Smith 62e0f454a0 DebugInfo: Remove 'inlinedAt:' field from MDLocalVariable
Remove 'inlinedAt:' from MDLocalVariable.  Besides saving some memory
(variables with it seem to be single largest `Metadata` contributer to
memory usage right now in -g -flto builds), this stops optimization and
backend passes from having to change local variables.

The 'inlinedAt:' field was used by the backend in two ways:

 1. To tell the backend whether and into what a variable was inlined.
 2. To create a unique id for each inlined variable.

Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg`
attachment, and change the DWARF backend to use a typedef called
`InlinedVariable` which is `std::pair<MDLocalVariable*, MDLocation*>`.
This `DebugLoc` is already passed reliably through the backend (as
verified by r234021).

This commit removes the check from r234021, but I added a new check
(that will survive) in r235048, and changed the `DIBuilder` API in
r235041 to require a `!dbg` attachment whose 'scope:` is in the same
`MDSubprogram` as the variable's.

If this breaks your out-of-tree testcases, perhaps the script I used
(mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778
in a moment.

llvm-svn: 235050
2015-04-15 22:29:27 +00:00
Anders Waldenborg 1433fd4699 Fix crash in DebugInfoFinder when adding a module with forward declared composite type
The testcase that is included in the patch caused a crash when doing DebugInfoFinder::processModule
on the module due to DCT->getElements() returning nullptr in DebugInfoFinder::processType.

By doing "DCT->getElements()" instead of "DCT->getElements()->operands()" one gets a DIArray
instead of a raw MDTuple. The former has code to handle null as a 0-element array and
therefore avoids the crash.

Differential Revision: http://reviews.llvm.org/D9008

llvm-svn: 234875
2015-04-14 09:18:17 +00:00
Duncan P. N. Exon Smith acdee690c8 DebugInfo: Update signature of DICompileUnit::replace*()
Change `DICompileUnit::replaceSubprograms()` and
`DICompileUnit::replaceGlobalVariables()` to match the `MDCompileUnit`
equivalents that they're wrapping.

llvm-svn: 234852
2015-04-14 03:51:36 +00:00
Duncan P. N. Exon Smith 537b4a8159 DebugInfo: Gut DISubprogram and DILexicalBlock*
Gut the `DIDescriptor` wrappers around `MDLocalScope` subclasses.  Note
that `DILexicalBlock` wraps `MDLexicalBlockBase`, not `MDLexicalBlock`.

llvm-svn: 234850
2015-04-14 03:40:37 +00:00
Duncan P. N. Exon Smith 20caafbfd6 DebugInfo: Gut DINamespace and DITemplate*Parameter
Continue gutting `DIDescriptor` subclasses, turning them into
as-bare-as-possible pointer wrappers.

llvm-svn: 234843
2015-04-14 03:01:27 +00:00
Duncan P. N. Exon Smith 7348ddaa74 DebugInfo: Gut DIVariable and DIGlobalVariable
Gut all the non-pointer API from the variable wrappers, except an
implicit conversion from `DIGlobalVariable` to `DIDescriptor`.  Note
that if you're updating out-of-tree code, `DIVariable` wraps
`MDLocalVariable` (`MDVariable` is a common base class shared with
`MDGlobalVariable`).

llvm-svn: 234840
2015-04-14 02:22:36 +00:00
Duncan P. N. Exon Smith 32e7f2860b DebugInfo: Move DIVariable::printExtendedName() to its only caller
Move the local function `printDebugLoc()` along with it.

llvm-svn: 234838
2015-04-14 02:09:32 +00:00
Duncan P. N. Exon Smith de8e427394 DebugInfo: Gut DIObjCProperty and DIImportedEntity
Gut a couple more classes in the DIDescriptor hierarchy.  Leave behind
an implicit conversion to `DIDescriptor`, the old base class.

llvm-svn: 234836
2015-04-14 01:46:44 +00:00
Duncan P. N. Exon Smith b7e221ba55 DebugInfo: Gut DILocation
This is along the same lines as r234832, but for `DILocation`.  Clean
out all accessors from `DILocation`.  Any callers should be using
`MDLocation` directly (e.g., via `operator->()`).

llvm-svn: 234835
2015-04-14 01:35:55 +00:00
Duncan P. N. Exon Smith 843237f573 DebugInfo: Move DILocation::computeNewDiscriminators()
As documented in PR23200 (and the FIXMEs I've added to the code here),
this logic is fairly broken: it modifies the `LLVMContext` in a way that
affects other modules and cannot be serialized to assembly/bitcode.  For
now, move it over to `MDLocation::computeNewDiscriminators()` anyway.

llvm-svn: 234825
2015-04-14 00:35:42 +00:00
Duncan P. N. Exon Smith 4fd839b0da AddDiscriminators: Create new MDLocation directly
I don't see a reason to add the `copyWithNewScope()` API over to
`MDLocation` -- it seems to be a holdover from when creating locations
required knowing details of operand layout -- so change
`AddDiscriminators` to call `MDLocation::get()` directly.  Should be no
functionality change here.

llvm-svn: 234824
2015-04-14 00:34:30 +00:00
Duncan P. N. Exon Smith 745a5db444 SelectionDAG: Stop using DIVariable::isInlinedFnArgument()
Instead of calling the somewhat confusingly-named
`DIVariable::isInlinedFnArgument()`, do the check directly here.
There's possibly a small functionality change here: instead of
`dyn_cast<>`'ing `DV->getScope()` to `MDSubprogram`, I'm looking up the
scope chain for the actual subprogram.  I suspect that this is a no-op
for function arguments so in practise there isn't a real difference.

I've also added a `FIXME` to check the `inlinedAt:` chain instead, since
I wonder if that would be more reliable than the
`MDSubprogram::describes()` function.

Since this was the only user of `DIVariable::isInlinedFnArgument()`,
delete it.

llvm-svn: 234799
2015-04-13 21:38:48 +00:00
Duncan P. N. Exon Smith cca5f68e53 DebugInfo: Remove DIGlobalVariable::getGlobal()
`DIGlobalVariable::getGlobal()` isn't really helpful, it just does a
`dyn_cast_or_null<>`.  Simplify its only user by doing the cast directly
and delete the code.

llvm-svn: 234796
2015-04-13 20:39:25 +00:00
Duncan P. N. Exon Smith 3c2d70434b DebugInfo: Migrate DISubprogram::describes() to new hierarchy, NFC
I don't really like this function at all -- I think it should be as
simple as `return getFunction() == F` -- but for now this seems like the
best we can do.

llvm-svn: 234778
2015-04-13 19:07:27 +00:00
Duncan P. N. Exon Smith c82570b68b Reapply "Verifier: Check for incompatible bit piece expressions"
This reverts commit r234717, reapplying r234698 (in spirit).

As described in r234717, the original `Verifier` check had a
use-after-free.  Instead of storing pointers to "interesting" debug info
intrinsics whose bit piece expressions should be verified once we have
typerefs, do a second traversal.  I've added a testcase to catch the
`llc` crasher.

Original commit message:

    Verifier: Check for incompatible bit piece expressions

    Convert an assertion into a `Verifier` check.  Bit piece expressions
    must fit inside the variable, and mustn't be the entire variable.
    Catching this in the verifier will help us find bugs sooner, and makes
    `DIVariable::getSizeInBits()` dead code.

llvm-svn: 234776
2015-04-13 18:53:11 +00:00
Duncan P. N. Exon Smith 5cd454161c Revert "Verifier: Check for incompatible bit piece expressions"
This reverts commit r234698.

This caused a use-after-free: `QueuedBitPieceExpressions` holds onto
references to `DbgInfoIntrinsic`s and references them past where they're
deleted (this is because the verifier is run as a function pass, and
then `verifyTypeRefs()` is called during `doFinalization()`).

I'll include a reduced crasher for `llc` when I recommit the check.

llvm-svn: 234717
2015-04-13 00:06:28 +00:00
Duncan P. N. Exon Smith 7ad0bd54d3 DebugInfo: Make MDSubprogram::getFunction() return Constant
Change `MDSubprogram::getFunction()` and
`MDGlobalVariable::getConstant()` to return a `Constant`.  Previously,
both returned `ConstantAsMetadata`.

llvm-svn: 234699
2015-04-11 20:27:40 +00:00
Duncan P. N. Exon Smith 5ad6ff76dc Verifier: Check for incompatible bit piece expressions
Convert an assertion into a `Verifier` check.  Bit piece expressions
must fit inside the variable, and mustn't be the entire variable.
Catching this in the verifier will help us find bugs sooner, and makes
`DIVariable::getSizeInBits()` dead code.

llvm-svn: 234698
2015-04-11 19:58:35 +00:00
Duncan P. N. Exon Smith 127ea4b616 DebugInfo: Remove dead DIDescriptor::replaceAllUsesWith()
r234696 replaced the only use of `DIDescriptor::replaceAllUsesWith()`
with `DIBuilder::replaceTemporary()` (added in r234695).  Delete the
dead code.

llvm-svn: 234697
2015-04-11 19:29:09 +00:00
Duncan P. N. Exon Smith 19f87726d5 DebugInfo: Assume a valid pointer for DISubprogram::getFunction()
llvm-svn: 234693
2015-04-11 18:15:48 +00:00
Duncan P. N. Exon Smith f0d81a50bf DebugInfo: Move DIScope::getName() and getContext() to MDScope
Continue gutting the `DIDescriptor` hierarchy.  In this case, move the
guts of `DIScope::getName()` and `DIScope::getContext()` to
`MDScope::getName()` and `MDScope::getScope()`.

llvm-svn: 234691
2015-04-11 17:37:23 +00:00
Duncan P. N. Exon Smith 50c065bc7d DebugInfo: Add forwarding getFilename() accessor to new hierarchy
Add forwarding `getFilename()` and `getDirectory()` accessors to nodes
in the new hierarchy that define a `getFile()`.  Use that to
re-implement existing functionality in the `DIDescriptor` hierarchy.

llvm-svn: 234671
2015-04-11 00:39:43 +00:00
Duncan P. N. Exon Smith 241982c380 DebugInfo: Remove dead DIDescriptor::getDescriptorField()
llvm-svn: 234665
2015-04-10 23:53:44 +00:00
Duncan P. N. Exon Smith 3d66c863cf DebugInfo: Remove constructors for DIRef<>
Remove all constructors for `DIRef<>` *except* the ones forwarding from
`TypedDebugNodeRef`.

llvm-svn: 234340
2015-04-07 18:41:54 +00:00
Duncan P. N. Exon Smith 1134473f51 IR: Remove MDTupleTypedArrayWrapper::operator MDTuple*()
Remove `MDTupleTypedArrayWrapper::operator MDTuple*()`, since it causes
ambiguity (at least in some [1] compilers [2]) when using indexes to
`MDTupleTypedArrayWrapper::operator[](unsigned)` that are convertible to
(but not the same as) `unsigned`.

[1]: http://lab.llvm.org:8011/builders/sanitizer-windows/builds/2308
[2]: http://lab.llvm.org:8011/builders/clang-cmake-mips/builds/4442

llvm-svn: 234326
2015-04-07 16:50:39 +00:00
Duncan P. N. Exon Smith 000fa2c646 DebugInfo: Remove DITypedArray<>, replace with typedefs
Replace all uses of `DITypedArray<>` with `MDTupleTypedArrayWrapper<>`
and `MDTypeRefArray`.  The APIs are completely different, but the
provided functionality is the same: treat an `MDTuple` as if it's an
array of a particular element type.

To simplify this patch a bit, I've temporarily typedef'ed
`DebugNodeArray` to `DIArray` and `MDTypeRefArray` to `DITypeArray`.
I've also temporarily conditionalized the accessors to check for null --
eventually these should be changed to asserts and the callers should
check for null themselves.

There's a tiny accompanying patch to clang.

llvm-svn: 234290
2015-04-07 04:14:33 +00:00
Duncan P. N. Exon Smith 8d33fdc3bf DebugInfo: Remove DICompositeType mutation API
Change `DIBuilder` to mutate `MDCompositeTypeBase` directly, and remove
the wrapping API in `DICompositeType`.

llvm-svn: 234289
2015-04-07 04:12:02 +00:00
Duncan P. N. Exon Smith 86cc332462 DebugInfo: Move DIExpression bit-piece API to MDExpression
llvm-svn: 234286
2015-04-07 03:49:59 +00:00
Duncan P. N. Exon Smith 76c9184434 DebugInfo: Remove special iterators from DIExpression
Remove special iterators from `DIExpression` in favour of same in
`MDExpression`.  There should be no functionality change here.

Note that the APIs are slightly different: `getArg(unsigned)` counts
from 0, not 1, in the `MDExpression` version of the iterator.

llvm-svn: 234285
2015-04-07 03:45:57 +00:00
Duncan P. N. Exon Smith 5261e4be99 DebugInfo: Move DIFlag-related API from DIDescriptor to DebugNode
llvm-svn: 234274
2015-04-07 01:21:40 +00:00
Duncan P. N. Exon Smith 9d1cf4c166 IR: Stop using DIDescriptor::is*() and auto-casting
`DIDescriptor`'s subclasses allow construction from incompatible
pointers, and `DIDescriptor` defines a series of `isa<>`-like functions
(e.g., `isCompileUnit()` instead of `isa<MDCompileUnit>()`) that clients
tend to use like this:

    if (DICompileUnit(N).isCompileUnit())
      foo(DICompileUnit(N));

These construction patterns work together to make `DIDescriptor` behave
differently from normal pointers.

Instead, use built-in `isa<>`, `dyn_cast<>`, etc., and only build
`DIDescriptor`s from pointers that are valid for their type.

I've split this into a few commits for different parts of LLVM and clang
(to decrease the patch size and increase the chance of review).
Generally the changes I made were NFC, but in a few places I made things
stricter if it made sense from the surrounded code.

Eventually a follow-up commit will remove the API for the "old" way.

llvm-svn: 234255
2015-04-06 23:18:49 +00:00
Duncan P. N. Exon Smith 5bf3cdc566 DebugInfo: Reimplement DIRef<>::resolve() using TypedDebugNodeRef<>
Gut `DIRef<>::resolve()`, reimplementing it using
`TypedDebugNodeRef<>::resolve()`.  Use three separate functions rather
than some sort of type traits, since the latter (i.e., mapping `DIScope`
=> `MDScope`) seems heavy-handed.  I don't expect `DIRef<>` to last much
longer in tree anyway.

As a drive-by fix, make `TypedDebugNodeRef<>::resolve()` do the right
thing with `nullptr`.

llvm-svn: 234248
2015-04-06 22:27:37 +00:00
Duncan P. N. Exon Smith 6d0b3704b3 DebugInfo: Drop confusing forwarding API from DILexicalBlockFile
Remove `DILexicalBlockFile::getScope()` (whose last use was removed from
clang in r234245), which illegally returned a `DILexicalBlock` despite
its scope sometimes being an `MDSubprogram`.  Also remove the
`getLineNumber()` and `getColumnNumber()` methods that just forwarded to
`DILexicalBlock`'s versions, since there don't seem to be any callers.

Note that the block of code removed from `DebugInfo.cpp` was actually
dead code, since `isLexicalBlock()` (the previous branch) always returns
true when `isLexicalBlockFile()` returns true.

An earlier (broken and untested) version of this was squashed into
r234222 and reverted in r234225.

llvm-svn: 234246
2015-04-06 22:07:46 +00:00
Duncan P. N. Exon Smith a5099dce62 DebugInfo: Remove DIDescriptor::Verify()
Remove `DIDescriptor::Verify()` and the `Verify()`s from subclasses.
They had already been gutted, and just did an `isa<>` check.

In a couple of cases I've temporarily dropped the check entirely, but
subsequent commits are going to disallow conversions to the
`DIDescriptor`s directly from `MDNode`, so the checks will come back in
another form soon enough.

llvm-svn: 234201
2015-04-06 19:49:39 +00:00
Duncan P. N. Exon Smith 3ec5fa6a1c DebugInfo: Use MDTypeRef throughout the hierarchy
Use `MDTypeRef` (etc.) in the new debug info hierarchy rather than raw
`Metadata *` pointers.

I rolled in a change to `DIBuilder` that looks unrelated: take `DIType`
instead of `DITypeRef` as type arguments when creating variables.
However, this was the simplest way to use `MDTypeRef` within the
functions, and didn't require any cleanups from callers in clang (since
they were all passing in `DIType`s anyway, relying on their implicit
conversions to `DITypeRef`).

llvm-svn: 234197
2015-04-06 19:03:45 +00:00
Duncan P. N. Exon Smith 930f388bad DebugInfo: Create MDTypeRef, etc., to replace DITypeRef
Create a string-based wrapper in the debug info hierarchy for type
references.

llvm-svn: 234188
2015-04-06 18:02:43 +00:00
Duncan P. N. Exon Smith 398069064d DebugInfo: Remove dead code for accessing fields
Most fields are now accessed via the new debug info hierarchy.  I'll
make the rest of this code dead soon.

llvm-svn: 234182
2015-04-06 17:21:05 +00:00
Duncan P. N. Exon Smith 897030c80c DebugInfo: Use MDFile instead of accessing operands directly, NFC
llvm-svn: 234175
2015-04-06 16:43:40 +00:00
Rafael Espindola 468b8688ce git-clang-format r233603.
Thanks to Meador Inge for noticing.

llvm-svn: 233808
2015-04-01 14:44:59 +00:00
Duncan P. N. Exon Smith 3ee34e14e1 Verifier: Move over DISubprogram::Verify()
Move over the remaining (somewhat complicated) check from
`DISubprogram::Verify()`.  I suspect this check could be optimized --
e.g., it would be nice not to do another full traversal here -- but it's
not exactly obvious how.  For now, just bring it over as is.

Once we have a better model for the "canonical" subprogram of a
`Function`, we should enforce that all `!dbg` attachments lead to the
canonical one.

llvm-svn: 233663
2015-03-31 02:09:55 +00:00
Duncan P. N. Exon Smith dd77af870f DebugInfo: Rewrite llvm::getDISubprogram(), NFC
Simplify implementation of `llvm::getDISubprogram()`.  I might go
through and see how difficult it is to update the users, since this
function doesn't really seem necessary anymore.

llvm-svn: 233662
2015-03-31 02:06:28 +00:00
Duncan P. N. Exon Smith 3b960c9da0 DebugInfo: Hide isScopeRef() and isTypeRef() behind NDEBUG
The copies of these in `lib/IR/DebugInfo.cpp` are apparently [1] only
used in assertions now, so hide them behind `#ifndef NDEBUG`.

[1]: http://lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/9238

llvm-svn: 233661
2015-03-31 01:47:55 +00:00
Duncan P. N. Exon Smith 85866b2a28 Verifier: Check reference flags in debug info
Move over checks of `&` and `&&` flags.

llvm-svn: 233658
2015-03-31 01:28:58 +00:00
Duncan P. N. Exon Smith 94d58f8880 Verifier: Move more debug info checks away from Verify()
Most of these checks were already in the `Verifier` so this is more of a
cleanup.  Now almost everything is over there.

Now that require a `name:` for `MDGlobalVariable`, add a check in
`LLParser` for it.

llvm-svn: 233657
2015-03-31 01:28:22 +00:00
Duncan P. N. Exon Smith cd07efa173 Verifier: Move checks over from DIDescriptor::Verify()
Move over some more checks from `DIDescriptor::Verify()`, and change
`LLParser` to require non-null `file:` fields in compile units.

I've ignored the comment in test/Assembler/metadata-null-operands.ll
since I disagree with it.  At the time that test was written (r229960),
the debug info verifier wasn't on by default, so my comment there is in
the context of not expecting the verifier to be useful.  It is now, and
besides that, since r233394 we can check when parsing textual IR whether
an operand is null that shouldn't be.

llvm-svn: 233654
2015-03-31 00:47:15 +00:00
Rafael Espindola 0d68b4c5ed Fix PR23045.
Keep a note in the materializer that we are stripping debug info so that
user doing a lazy read of the module don't hit outdated formats.

Thanks to Duncan for suggesting the fix.

llvm-svn: 233603
2015-03-30 21:36:43 +00:00
Rafael Espindola 43006fba08 Use range loops and add missing braces.
llvm-svn: 233598
2015-03-30 21:18:36 +00:00
Duncan P. N. Exon Smith ab659fb3d0 IR: Use the new DebugLoc API, NFC
Update lib/IR and lib/Bitcode to use the new `DebugLoc` API.  Added an
explicit conversion to `bool` (avoiding a conversion to `MDLocation`),
since a couple of these use cases need to handle broken code.

llvm-svn: 233585
2015-03-30 19:40:05 +00:00
Duncan P. N. Exon Smith 51306ef9bc DebugInfo: Reflow printDebugLoc() to use early returns, NFC
llvm-svn: 233580
2015-03-30 18:45:11 +00:00
Duncan P. N. Exon Smith 8f7bc7919b DebugInfo: Implement MDLocation::getInlinedAtScope()
Write `MDLocation::getInlinedAtScope()` and use it to re-implement
`DebugLoc::getScopeNode()` (and simplify `DISubprogram::Verify()`).
This follows the inlined-at linked list and returns the scope of the
deepest/last location.

llvm-svn: 233568
2015-03-30 17:41:24 +00:00
Duncan P. N. Exon Smith 215e7edfe0 DebugInfo: Simplify logic in DISubprogram::Verify(), NFC
Simplify the logic in `DISubprogram::Verify()` by using the new debug
info hierarchy directly instead of the `DebugLoc` wrapper.

llvm-svn: 233563
2015-03-30 17:06:38 +00:00
Peter Collingbourne b736065f78 DebugInfo: Permit DW_TAG_structure_type, DW_TAG_member, DW_TAG_typedef tags with empty file names.
Some languages, such as Go, have pre-defined structure types (e.g. "string"
is essentially a pointer/length pair) or pre-defined "typedef" types
(e.g. "error" is essentially a typedef for a specific interface type).
Such types do not have associated source location, so a Go frontend would
be correct not to associate a file name with such types.

This change relaxes the DIType verifier to permit unlocated types with
these tags.

Differential Revision: http://reviews.llvm.org/D8588

llvm-svn: 233200
2015-03-25 17:44:49 +00:00
Duncan P. N. Exon Smith 9b9cc2dad4 DebugInfo: Overload get() in DIDescriptor subclasses
Continue to simplify the `DIDescriptor` subclasses, so that they behave
more like raw pointers.  Remove `getRaw()`, replace it with an
overloaded `get()`, and overload the arrow and cast operators.  Two
testcases started to crash on the arrow operators with this change
because of `scope:` references that weren't real scopes.  I fixed them.
Soon I'll add verifier checks for them too.

This also adds explicit dereference operators.  Previously, the builtin
dereference against `operator MDNode *()` would have worked, but now the
builtins are ambiguous.

llvm-svn: 233030
2015-03-23 21:54:07 +00:00
Duncan P. N. Exon Smith d4e07c973c DebugInfoFinder: Check for null imported entities
Don't use the accessors in `DIImportedEntity` on a null pointer.  (A WIP
patch to make `DIDescriptor` accessors more strict crashes here
otherwise.)

llvm-svn: 232833
2015-03-20 19:13:53 +00:00
Duncan P. N. Exon Smith e9d379c038 IR: Take advantage of -verify checks for MDExpression
Now that we check `MDExpression` during `-verify` (r232299), make
the `DIExpression` wrapper more strict:

  - remove redundant checks in `DebugInfoVerifier`,
  - overload `get()` to `cast_or_null<MDExpression>` (superseding
    `getRaw()`),
  - stop checking for null in any accessor, and
  - remove `DIExpression::Verify()` entirely in favour of
    `MDExpression::isValid()`.

There is still some logic in this class, mostly to do with high-level
iterators; I'll defer cleaning up those until the rest of the wrappers
are similarly strict.

llvm-svn: 232412
2015-03-16 21:03:55 +00:00
Duncan P. N. Exon Smith f37404033f DebugInfo: Simplify logic in DIType::Verify(), NFC
Clarify the logic in `DIType::Verify()` by checking `isBasicType()`
earlier, by skipping `else` after `return`s, and by documenting an
otherwise opaque check.

No functionality change.

llvm-svn: 232410
2015-03-16 20:46:27 +00:00
Adrian Prantl 0f61579602 Fix DwarfExpression::AddMachineRegExpression so it doesn't read past the
end of an expression that ends with DW_OP_plus.
Caught by the ASAN build bots.

llvm-svn: 231260
2015-03-04 17:39:33 +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
Duncan P. N. Exon Smith 9c3b89448a DebugInfo: Use TempMDNode in DIDescriptor::replaceAllUsesWith()
Start using `TempMDNode` in `DIDescriptor::replaceAllUsesWith()`
(effectively `std::unique_ptr<MDNode, MDNode::deleteTemporary>`).

Besides making ownership more explicit, this prepares for when
`DIDescriptor` refers to nodes that are *not* `MDTuple`.  The old logic
for "replacing" a node with itself used `MDNode::get()` to return a new
(uniqued) `MDTuple`, while the new logic just defers to
`MDNode::replaceWithUniqued()` (which also typically saves an allocation
and RAUW traffic by mutating the temporary in place).

llvm-svn: 230879
2015-02-28 23:48:02 +00:00
Duncan P. N. Exon Smith 269e38d397 IR: Add helper to split debug info flags bitfield
Split debug info 'flags' bitfield over a vector so the current flags can
be iterated over.  This API (in combination with r230107) will be used
for assembly support for symbolic constants.

llvm-svn: 230108
2015-02-21 00:45:26 +00:00