Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.
Patch by Sander de Smalen.
Reviewers: echristo, pcc, aprantl
Reviewed By: aprantl
Subscribers: fhahn, javed.absar, aprantl, llvm-commits
Differential Revision: https://reviews.llvm.org/D33894
llvm-svn: 305386
Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.
Patch by Sander de Smalen.
Reviewers: pcc, echristo, aprantl
Reviewed By: aprantl
Subscribers: fhahn, aprantl, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33892
llvm-svn: 305304
Fixes inalloca parameters, which previously all pointed to the same
offset. Extend the test to use llvm-readobj so that we can test the
offset in a readable way.
llvm-svn: 302578
Fixes the issue highlighted in
http://lists.llvm.org/pipermail/cfe-dev/2014-June/037500.html.
The DW_AT_decl_file and DW_AT_decl_line attributes on namespaces can
prevent LLVM from uniquing types that are in the same namespace. They
also don't carry any meaningful information.
rdar://problem/17484998
Differential Revision: https://reviews.llvm.org/D32648
llvm-svn: 301706
This is a follow up to the fix in r298360 to improve the handling of debug
values when redundant LEAs are removed. The fix in r298360 effectively
discarded the debug values. This patch now attempts to preserve the debug
values by using the DWARF DW_OP_stack_value operation via prependDIExpr.
Moved functions appendOffset and prependDIExpr from Local.cpp to
DebugInfoMetadata.cpp and made them available as static member functions of
DIExpression.
Differential Revision: https://reviews.llvm.org/D31604
llvm-svn: 301630
DISubprogram currently has 10 pointer operands, several of which are
often nullptr. This patch reduces the amount of memory allocated by
DISubprogram by rearranging the operands such that containing type,
template params, and thrown types come last, and are only allocated
when they are non-null (or followed by non-null operands).
This patch also eliminates the entirely unused DisplayName operand.
This saves up to 4 pointer operands per DISubprogram. (I tried
measuring the effect on peak memory usage on an LTO link of an X86
llc, but the results were very noisy).
This reapplies r301498 with an attempted workaround for g++.
Differential Revision: https://reviews.llvm.org/D32560
llvm-svn: 301501
DISubprogram currently has 10 pointer operands, several of which are
often nullptr. This patch reduces the amount of memory allocated by
DISubprogram by rearranging the operands such that containing type,
template params, and thrown types come last, and are only allocated
when they are non-null (or followed by non-null operands).
This patch also eliminates the entirely unused DisplayName operand.
This saves up to 4 pointer operands per DISubprogram. (I tried
measuring the effect on peak memory usage on an LTO link of an X86
llc, but the results were very noisy).
llvm-svn: 301498
For Swift we would like to be able to encode the error types that a
function may throw, so the debugger can display them alongside the
function's return value when finish-ing a function.
DWARF defines DW_TAG_thrown_type (intended to be used for C++ throw()
declarations) that is a perfect fit for this purpose. This patch wires
up support for DW_TAG_thrown_type in LLVM by adding a list of thrown
types to DISubprogram.
To offset the cost of the extra pointer, there is a follow-up patch
that turns DISubprogram into a variable-length node.
rdar://problem/29481673
Differential Revision: https://reviews.llvm.org/D32559
llvm-svn: 301489
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
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
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
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
so we can stop using DW_OP_bit_piece with the wrong semantics.
The entire back story can be found here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20161114/405934.html
The gist is that in LLVM we've been misinterpreting DW_OP_bit_piece's
offset field to mean the offset into the source variable rather than
the offset into the location at the top the DWARF expression stack. In
order to be able to fix this in a subsequent patch, this patch
introduces a dedicated DW_OP_LLVM_fragment operation with the
semantics that we used to apply to DW_OP_bit_piece, which is what we
actually need while inside of LLVM. This patch is complete with a
bitcode upgrade for expressions using the old format. It does not yet
fix the DWARF backend to use DW_OP_bit_piece correctly.
Implementation note: We discussed several options for implementing
this, including reserving a dedicated field in DIExpression for the
fragment size and offset, but using an custom operator at the end of
the expression works just fine and is more efficient because we then
only pay for it when we need it.
Differential Revision: https://reviews.llvm.org/D27361
rdar://problem/29335809
llvm-svn: 288683
Change type of some missed DebugInfo-related alignment variables,
that are still uint64_t, to uint32_t.
Original change introduced in r284482.
llvm-svn: 285242
Summary:
Fixes PR28281.
MSVC lists indirect virtual base classes in the field list of a class,
using LF_IVBCLASS records. This change makes LLVM emit such records
when processing DW_TAG_inheritance tags with the DIFlagVirtual and
(newly introduced) DIFlagIndirect tags.
Reviewers: rnk, ruiu, zturner
Differential Revision: https://reviews.llvm.org/D25578
llvm-svn: 285130
- Add alignment attribute to DIVariable family
- Modify bitcode format to match new DIVariable representation
- Update tests to match these changes (also add bitcode upgrade test)
- Expect that frontend passes non-zero align value only when it is not default
(was forcibly aligned by alignas()/_Alignas()/__atribute__(aligned())
Differential Revision: https://reviews.llvm.org/D25073
llvm-svn: 284678
In futher patches we shall have alignment field added to DIVariable family
and switching from uint64_t to uint32_t will save 4 bytes per variable.
Differential Revision: https://reviews.llvm.org/D25620
llvm-svn: 284482
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.
Fixes PR30362. A program for upgrading test cases is attached to that
bug.
Differential Revision: http://reviews.llvm.org/D20147
llvm-svn: 281284
Use ADT/BitmaskEnum for DINode::DIFlags for the following purposes:
Get rid of unsigned int for flags to avoid problems on platforms with sizeof(int) < 4
Flags are now strongly typed
Patch by: Victor Leschuk <vleschuk@gmail.com>
Differential Revision: https://reviews.llvm.org/D23766
llvm-svn: 280700
Use ADT/BitmaskEnum for DINode::DIFlags for the following purposes:
* Get rid of unsigned int for flags to avoid problems on platforms with sizeof(int) < 4
* Flags are now strongly typed
Patch by: Victor Leschuk <vleschuk@gmail.com>
Differential Revision: https://reviews.llvm.org/D23766
llvm-svn: 280686
In cases where .dwo/.dwp files are guaranteed to be available, skipping
the extra online (in the .o file) inline info can save a substantial
amount of space - see the original r221306 for more details there.
llvm-svn: 279650
Summary:
This represents the adjustment applied to the implicit 'this' parameter
in the prologue of a virtual method in the MS C++ ABI. The adjustment is
always zero unless multiple inheritance is involved.
This increases the size of DISubprogram by 8 bytes, unfortunately. The
adjustment really is a signed 32-bit integer. If this size increase is
too much, we could probably win it back by splitting out a subclass with
info specific to virtual methods (virtuality, vindex, thisadjustment,
containingType).
Reviewers: aprantl, dexonsmith
Subscribers: aaboud, amccarth, llvm-commits
Differential Revision: http://reviews.llvm.org/D21614
llvm-svn: 274325
Summary:
This seems like the least intrusive way to pass this information
through.
Fixes PR28151
Reviewers: majnemer, aprantl, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D21444
llvm-svn: 273053
Summary:
Now DISubroutineType has a 'cc' field which should be a DW_CC_ enum. If
it is present and non-zero, the backend will emit it as a
DW_AT_calling_convention attribute. On the CodeView side, we translate
it to the appropriate enum for the LF_PROCEDURE record.
I added a new LLVM vendor specific enum to the list of DWARF calling
conventions. DWARF does not appear to attempt to standardize these, so I
assume it's OK to do this until we coordinate with GCC on how to emit
vectorcall convention functions.
Reviewers: dexonsmith, majnemer, aaboud, amccarth
Subscribers: mehdi_amini, llvm-commits
Differential Revision: http://reviews.llvm.org/D21114
llvm-svn: 272197
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
The only functionality change was removing an error check from the
BitcodeReader (and an assertion from DILocation::getImpl) that is
already caught by Verifier::visitDILocation. The Verifier is a better
place for this anyway, and being inconsistent with other subclasses of
MDNode isn't serving anyone.
llvm-svn: 267267
Before this fix, DILexicalBlockFile entries were skipped only in some cases and were not in other cases.
Differential Revision: http://reviews.llvm.org/D18724
llvm-svn: 267004
Add a new method, DICompositeType::buildODRType, that will create or
mutate the DICompositeType for a given ODR identifier, and use it in
LLParser and BitcodeReader instead of DICompositeType::getODRType.
The logic is as follows:
- If there's no node, create one with the given arguments.
- Else, if the current node is a forward declaration and the new
arguments would create a definition, mutate the node to match the
new arguments.
- Else, return the old node.
This adds a missing feature supported by the current DITypeIdentifierMap
(which I'm slowly making redudant). The only remaining difference is
that the DITypeIdentifierMap has a "the-last-one-wins" rule, whereas
DICompositeType::buildODRType has a "the-first-one-wins" rule.
For now I'm leaving behind DICompositeType::getODRType since it has
obvious, low-level semantics that are convenient for unit testing.
llvm-svn: 266786
Lift the API for debug info ODR type uniquing up a layer. Instead of
clients managing the map directly on the LLVMContext, add a static
method to DICompositeType called getODRType and handle the map in the
background. Also adds DICompositeType::getODRTypeIfExists, so far just
for convenience in the unit tests.
This simplifies the logic in LLParser and BitcodeReader. Because of
argument spam there are actually a few more lines of code now; I'll see
if I come up with a reasonable way to clean that up.
llvm-svn: 266742
Rather than relying on the structural equivalence of DICompositeType to
merge type definitions, use an explicit map on the LLVMContext that
LLParser and BitcodeReader consult when constructing new nodes.
Each non-forward-declaration DICompositeType with a non-empty
'identifier:' field is stored/loaded from the type map, and the first
definiton will "win".
This map is opt-in: clients that expect ODR types from different modules
to be merged must call LLVMContext::ensureDITypeMap.
- Clients that just happen to load more than one Module in the same
LLVMContext won't magically merge types.
- Clients (like LTO) that want to continue to merge types based on ODR
identifiers should opt-in immediately.
I have updated LTOCodeGenerator.cpp, the two "linking" spots in
gold-plugin.cpp, and llvm-link (unless -disable-debug-info-type-map) to
set this.
With this in place, it will be straightforward to remove the DITypeRef
concept (i.e., referencing types by their 'identifier:' string rather
than pointing at them directly).
llvm-svn: 266549
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
This mostly cosmetic patch moves the DebugEmissionKind enum from DIBuilder
into DICompileUnit. DIBuilder is not the right place for this enum to live
in — a metadata consumer should not have to include DIBuilder.h.
I also added a Verifier check that checks that the emission kind of a
DICompileUnit is actually legal.
http://reviews.llvm.org/D18612
<rdar://problem/25427165>
llvm-svn: 265077
MDString are uniqued in the Context on creation, hashing the
pointer is less expensive than hashing the String itself.
Reviewers: dexonsmith
Differential Revision: http://reviews.llvm.org/D16560
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 263867
Introduced DIMacro and DIMacroFile debug info metadata in the LLVM IR to support macros.
Differential Revision: http://reviews.llvm.org/D14687
llvm-svn: 255245
Florian Hahn