2934 Commits

Author SHA1 Message Date
Adrian Prantl
4e5d08aad0 Revert "Debug Info: Bail out of AddMachineRegPiece() if MachineReg is not a"
This reverts commit r225852, it was a bad idea.

MachineReg should always be a physical register. If it isn't this DebugLoc
shouldn't have been created in the first place.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225857 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 00:15:12 +00:00
Adrian Prantl
bc42415f0f Debug Info: Bail out of AddMachineRegPiece() if MachineReg is not a
physical register. The call to getMinimalPhysRegClass() later on asserts
on this condition.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225852 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 23:39:15 +00:00
Adrian Prantl
57ed5ffc76 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225851 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 23:39:11 +00:00
Adrian Prantl
9fb34c5169 cleanup.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225848 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 23:11:51 +00:00
Adrian Prantl
82df5a6981 Document, cleanup, and clang-format DwarfExpression.h
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225847 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 23:11:07 +00:00
Adrian Prantl
78415546e9 Debug Info: Turn DIExpression::getFrameRegister() into an isFrameRegister()
function.

NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225846 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 23:10:43 +00:00
Reid Kleckner
221a7075cf Add the llvm.frameallocate and llvm.recoverframeallocation intrinsics
These intrinsics allow multiple functions to share a single stack
allocation from one function's call frame. The function with the
allocation may only perform one allocation, and it must be in the entry
block.

Functions accessing the allocation call llvm.recoverframeallocation with
the function whose frame they are accessing and a frame pointer from an
active call frame of that function.

These intrinsics are very difficult to inline correctly, so the
intention is that they be introduced rarely, or at least very late
during EH preparation.

Reviewers: echristo, andrew.w.kaylor

Differential Revision: http://reviews.llvm.org/D6493

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225746 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 00:48:10 +00:00
Adrian Prantl
75212344d1 Debug Info: Move support for constants into DwarfExpression.
Move the declaration of DebugLocDwarfExpression into DwarfExpression.h
because it needs to be accessed from AsmPrinterDwarf.cpp and DwarfDebug.cpp

NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225734 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 00:04:06 +00:00
Adrian Prantl
df545e8d6c Make DwarfExpression store the AsmPrinter instead of the TargetMachine.
NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225731 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 23:36:56 +00:00
Adrian Prantl
0ec7e836f9 remove extra semicolon
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225730 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 23:36:50 +00:00
Adrian Prantl
2f95648566 Run clang-format on the parts of AsmPrinterDwarf where it improves the
readability.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225726 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 23:03:23 +00:00
Adrian Prantl
34ae4e7151 Debug Info: Add a virtual destructor to DwarfExpression.
Thanks Chandler for noticing!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225724 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 22:59:28 +00:00
Adrian Prantl
3d6fed1a57 Untwine this expression. Thanks to David for noticing!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225720 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 22:39:14 +00:00
Adrian Prantl
8afb6d0e2f Debug Info: Implement DwarfUnit::addRegisterOpPiece() using DwarfExpression.
NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225717 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 22:37:16 +00:00
Adrian Prantl
93eb099f24 Debug Info: Implement DwarfUnit::addRegisterOffset using DwarfExpression.
No functional change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225707 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 22:19:26 +00:00
Adrian Prantl
f89325d832 Debug info: Factor out the creation of DWARF expressions from AsmPrinter
into a new class DwarfExpression that can be shared between AsmPrinter
and DwarfUnit.

This is the first step towards unifying the two entirely redundant
implementations of dwarf expression emission in DwarfUnit and AsmPrinter.

Almost no functional change — Testcases were updated because asm comments
that used to be on two lines now appear on the same line, which is
actually preferable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225706 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 22:19:22 +00:00
Adrian Prantl
31208c1591 Update a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225399 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-07 21:35:13 +00:00
Adrian Prantl
7950596b55 Debug info: Allow aggregate types to be described by constants.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225378 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-07 20:48:58 +00:00
Philip Reames
28fa9e1e9f Introduce an example statepoint GC strategy
This change includes the most basic possible GCStrategy for a GC which is using the statepoint lowering code. At the moment, this GCStrategy doesn't really do much - aside from actually generate correct stackmaps that is - but I went ahead and added a few extra correctness checks as proof of concept. It's mostly here to provide documentation on how to do one, and to provide a point for various optimization legality hooks I'd like to add going forward. (For context, see the TODOs in InstCombine around gc.relocate.)

Most of the validation logic added here as proof of concept will soon move in to the Verifier.  That move is dependent on http://reviews.llvm.org/D6811

There was discussion in the review thread about addrspace(1) being reserved for something.  I'm going to follow up on a seperate llvmdev thread.  If needed, I'll update all the code at once.

Note that I am deliberately not making a GCStrategy required to use gc.statepoints with this change. I want to give folks out of tree - including myself - a chance to migrate. In a week or two, I'll make having a GCStrategy be required for gc.statepoints. To this end, I added the gc tag to one of the test cases but not others.

Differential Revision: http://reviews.llvm.org/D6808



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225365 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-07 19:07:50 +00:00
Frederic Riss
0c36e97b78 Make DIE.h a public CodeGen header.
dsymutil would like to use all the AsmPrinter/MCStreamer infrastructure
to stream out the DWARF. In order to do so, it will reuse the DIE object
and so this header needs to be public.

The interface exposed here has some corners that cannot be used without a
DwarfDebug object, but clients that want to stream Dwarf can just avoid
these.

Differential Revision: http://reviews.llvm.org/D6695

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225208 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-05 21:29:41 +00:00
David Blaikie
1d68fc5021 DebugInfo: Omit is_stmt from line table entries on the same line.
GCC does this for non-zero discriminators and since GCC doesn't produce
column info, that was the only place it comes up there. For LLVM, since
we can emit discriminators and/or column info, it makes more sense to
invert the condition and just test for changes in line number.

This should resolve at least some of the GDB 7.5 test suite failures
created by recent Clang changes that increase the location fidelity
(which, since Clang defaults to including column info on Linux by
default created a bunch of cases that confused GDB).

In theory we could do this better/differently by grouping actual source
statements together in a similar manner to the way lexical scopes are
handled but given that GDB isn't really in a position to consume that (&
users are probably somewhat used to different lines being different
'statements') this seems the safest and cheapest change. (I'm concerned
that doing this 'right' would bloat the debugloc data even further -
something Duncan's working hard to address)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225011 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-30 22:47:13 +00:00
Peter Collingbourne
d8ae3e1fee x86_64: Fix calls to __morestack under the large code model.
Under the large code model, we cannot assume that __morestack lives within
2^31 bytes of the call site, so we cannot use pc-relative addressing. We
cannot perform the call via a temporary register, as the rax register may
be used to store the static chain, and all other suitable registers may be
either callee-save or used for parameter passing. We cannot use the stack
at this point either because __morestack manipulates the stack directly.

To avoid these issues, perform an indirect call via a read-only memory
location containing the address.

This solution is not perfect, as it assumes that the .rodata section
is laid out within 2^31 bytes of each function body, but this seems to
be sufficient for JIT.

Differential Revision: http://reviews.llvm.org/D6787

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225003 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-30 20:05:19 +00:00
Timur Iskhodzhanov
f4076dc995 Band-aid fix for PR22032: don't emit DWARF debug info if AddressSanitizer is enabled on Windows
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224860 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-26 17:00:51 +00:00
David Majnemer
e277a13a71 CodeGen: Error on redefinitions instead of asserting
It's possible to have a prior definition of a symbol in module asm.
Raise an error instead of crashing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224828 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-24 23:06:55 +00:00
David Majnemer
d36cad9914 CodeGen: Allow aliases to be overridden by variables
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224827 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-24 22:44:29 +00:00
David Majnemer
e54eacce75 MC: Label definitions are permitted after .set directives
.set directives may be overridden by other .set directives as well as
label definitions.

This fixes PR22019.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224811 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-24 10:27:50 +00:00
Adrian Prantl
34f81e8bec Debug Info: In symmetry to DW_TAG_pointer_type, do not emit the byte size
of a DW_TAG_ptr_to_member_type.
This restores the behavior from before r224780-r224781.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224799 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-24 01:17:51 +00:00
Reid Kleckner
b60b7360f5 EH: Sink computation of local PadMap variable into function that uses it
No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224635 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 22:30:08 +00:00
Reid Kleckner
0f85d54670 Add the ExceptionHandling::MSVC enumeration
It is intended to be used for a family of personality functions that
have similar IR preparation requirements. Typically when interoperating
with MSVC personality functions, bits of functionality need to be
outlined from the main function into helper functions. There is also
usually more than one landing pad per invoke, which does not match the
LLVM IR landingpad representation.

None of this is implemented yet. This change just adds a new enum that
is active for *-windows-msvc and delegates to the EH removal preparation
pass.  No functionality change for other targets.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224625 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 22:19:48 +00:00
Adrian Prantl
7a6f0084e2 Explain why LLVM is emitting a DW_AT_containing_type inside of a class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224555 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 00:01:20 +00:00
Toma Tabacu
3fea427a63 [mips] Set GCC-compatible MIPS asssembler options before inline asm blocks.
Summary:
When generating MIPS assembly, LLVM always overrides the default assembler options by emitting the '.set noreorder', '.set nomacro' and '.set noat' directives,
while GCC uses the default options if an assembly-level function contains inline assembly code.

This becomes a problem when the code generated by LLVM is interleaved with inline assembly which assumes GCC-like assembler options (from Linux, for example).

This patch fixes these conflicts by setting the appropriate assembler options at the beginning of an inline asm block and popping them at the end.

Reviewers: dsanders

Reviewed By: dsanders

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6637

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224425 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-17 10:56:16 +00:00
David Blaikie
7c3af9120c PR21875: codegen for non-type template parameters of nullptr_t type
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224399 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-17 00:43:22 +00:00
Matt Arsenault
8b5b0f5ee5 Move lowerConstant to AsmPrinter
This was a static function before, and NVPTX duplicated it
because it wasn't exposed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224354 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-16 19:16:14 +00:00
Aaron Ballman
51c2bdca72 Fixing -Wsign-compare warnings; NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224337 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-16 14:04:11 +00:00
Adrian Prantl
6f059afde6 ARM/AArch64: Attach the FrameSetup MIFlag to CFI instructions.
Debug info marks the first instruction without the FrameSetup flag
as being the end of the function prologue. Any CFI instructions in the
middle of the function prologue would cause debug info to end the prologue
too early and worse, attach the line number of the CFI instruction, which
incidentally is often 0.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224294 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-16 00:20:49 +00:00
Michael Ilseman
9ecdca9115 Silence more static analyzer warnings.
Add in definedness checks for shift operators, null checks when
pointers are assumed by the code to be non-null, and explicit
unreachables.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224255 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-15 18:48:43 +00:00
Ekaterina Romanova
e0b0363e44 A fix for PR21176.
DW_OP_const <const> doesn't describe a constant value, but a value at a constant address. 
The proper way to describe a constant value is DW_OP_constu <const>, DW_OP_stack_value. 
Added DW_OP_stack_value to the stack. 

Marked incorrect-variable-debugloc1.ll to xfail for PowerPC64, while the the failure (PR21881) 
is being investigated. 



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224098 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-12 05:11:47 +00:00
Ekaterina Romanova
e9afc33de5 Reverting commit 223981, because the test that I added (incorrect-variable-debugloc1.ll) failed for llvm-ppc64.
The test is failing for llvm-ppc64 because for this platform the location list is not being generated at all (most likely because of the bug in PPC code optimization or generation). I will file a bug agains PPC compiler, but meanwhile, until PPC bug is fixed, I will have to revert my change.  



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224000 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-11 06:22:35 +00:00
Philip Reames
5e62b8471d GCStrategy should not own GCFunctionInfo
This change moves the ownership and access of GCFunctionInfo (the object which describes the safepoints associated with a safepoint under GCRoot) to GCModuleInfo. Previously, this was owned by GCStrategy which was in turned owned by GCModuleInfo. This made GCStrategy module specific which is 'surprising' given it's name and other purposes.

There's a few more changes needed, but we're getting towards the point we can reuse GCStrategy for gc.statepoint as well.

p.s. The style of this code ends up being a mess. I was trying to move code around without otherwise changing much. Once I get the ownership structure rearranged, I will go through and fixup spacing, naming, comments etc.

Differential Revision: http://reviews.llvm.org/D6587



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223994 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-11 01:47:23 +00:00
Ekaterina Romanova
de68a563bc A fix for PR21176.
DW_OP_const <const> doesn't describe a constant value, but a value at a constant address.
The proper way to describe a constant value is DW_OP_constu <const>, DW_OP_stack_value.

Added DW_OP_stack_value to the stack.

-This line, and those below, will be ignored--

M    lib/CodeGen/AsmPrinter/DwarfDebug.cpp
A    test/DebugInfo/incorrect-variable-debugloc1.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223981 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-10 23:19:56 +00:00
Philip Reames
3490d23337 Remove the Module pointer from GCStrategy and GCMetadataPrinter
In the current implementation, GCStrategy is a part of the ownership structure for the gc metadata which describes a Module. It also contains a reference to the module in question. As a result, GCStrategy instances are essentially Module specific.

I plan to transition away from this design. Instead, a GCStrategy will be owned by the LLVMContext. It will be a lightweight policy object which contains no information about the Modules or Functions involved, but can be easily reached given a Function.

The first step in this transition is to remove the direct Module reference from GCStrategy. This also requires removing the single user of this reference, the GCMetadataPrinter hierarchy. In theory, this will allow the lifetime of the printers to be scoped to the LLVMContext as well, but in practice, I'm not actually changing that. (Yet?)

An alternate design would have been to move the direct Module reference into the GCMetadataPrinter and change the keying of the owning maps to explicitly key off both GCStrategy and Module. I'm open to doing it that way instead, but didn't see much value in preserving the per Module association for GCMetadataPrinters.

The next change in this sequence will be to start unwinding the intertwined ownership between GCStrategy, GCModuleInfo, and GCFunctionInfo.

Differential Revision: http://reviews.llvm.org/D6566



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223859 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-09 23:57:54 +00:00
Duncan P. N. Exon Smith
dad20b2ae2 IR: Split Metadata from Value
Split `Metadata` away from the `Value` class hierarchy, as part of
PR21532.  Assembly and bitcode changes are in the wings, but this is the
bulk of the change for the IR C++ API.

I have a follow-up patch prepared for `clang`.  If this breaks other
sub-projects, I apologize in advance :(.  Help me compile it on Darwin
I'll try to fix it.  FWIW, the errors should be easy to fix, so it may
be simpler to just fix it yourself.

This breaks the build for all metadata-related code that's out-of-tree.
Rest assured the transition is mechanical and the compiler should catch
almost all of the problems.

Here's a quick guide for updating your code:

  - `Metadata` is the root of a class hierarchy with three main classes:
    `MDNode`, `MDString`, and `ValueAsMetadata`.  It is distinct from
    the `Value` class hierarchy.  It is typeless -- i.e., instances do
    *not* have a `Type`.

  - `MDNode`'s operands are all `Metadata *` (instead of `Value *`).

  - `TrackingVH<MDNode>` and `WeakVH` referring to metadata can be
    replaced with `TrackingMDNodeRef` and `TrackingMDRef`, respectively.

    If you're referring solely to resolved `MDNode`s -- post graph
    construction -- just use `MDNode*`.

  - `MDNode` (and the rest of `Metadata`) have only limited support for
    `replaceAllUsesWith()`.

    As long as an `MDNode` is pointing at a forward declaration -- the
    result of `MDNode::getTemporary()` -- it maintains a side map of its
    uses and can RAUW itself.  Once the forward declarations are fully
    resolved RAUW support is dropped on the ground.  This means that
    uniquing collisions on changing operands cause nodes to become
    "distinct".  (This already happened fairly commonly, whenever an
    operand went to null.)

    If you're constructing complex (non self-reference) `MDNode` cycles,
    you need to call `MDNode::resolveCycles()` on each node (or on a
    top-level node that somehow references all of the nodes).  Also,
    don't do that.  Metadata cycles (and the RAUW machinery needed to
    construct them) are expensive.

  - An `MDNode` can only refer to a `Constant` through a bridge called
    `ConstantAsMetadata` (one of the subclasses of `ValueAsMetadata`).

    As a side effect, accessing an operand of an `MDNode` that is known
    to be, e.g., `ConstantInt`, takes three steps: first, cast from
    `Metadata` to `ConstantAsMetadata`; second, extract the `Constant`;
    third, cast down to `ConstantInt`.

    The eventual goal is to introduce `MDInt`/`MDFloat`/etc. and have
    metadata schema owners transition away from using `Constant`s when
    the type isn't important (and they don't care about referring to
    `GlobalValue`s).

    In the meantime, I've added transitional API to the `mdconst`
    namespace that matches semantics with the old code, in order to
    avoid adding the error-prone three-step equivalent to every call
    site.  If your old code was:

        MDNode *N = foo();
        bar(isa             <ConstantInt>(N->getOperand(0)));
        baz(cast            <ConstantInt>(N->getOperand(1)));
        bak(cast_or_null    <ConstantInt>(N->getOperand(2)));
        bat(dyn_cast        <ConstantInt>(N->getOperand(3)));
        bay(dyn_cast_or_null<ConstantInt>(N->getOperand(4)));

    you can trivially match its semantics with:

        MDNode *N = foo();
        bar(mdconst::hasa               <ConstantInt>(N->getOperand(0)));
        baz(mdconst::extract            <ConstantInt>(N->getOperand(1)));
        bak(mdconst::extract_or_null    <ConstantInt>(N->getOperand(2)));
        bat(mdconst::dyn_extract        <ConstantInt>(N->getOperand(3)));
        bay(mdconst::dyn_extract_or_null<ConstantInt>(N->getOperand(4)));

    and when you transition your metadata schema to `MDInt`:

        MDNode *N = foo();
        bar(isa             <MDInt>(N->getOperand(0)));
        baz(cast            <MDInt>(N->getOperand(1)));
        bak(cast_or_null    <MDInt>(N->getOperand(2)));
        bat(dyn_cast        <MDInt>(N->getOperand(3)));
        bay(dyn_cast_or_null<MDInt>(N->getOperand(4)));

  - A `CallInst` -- specifically, intrinsic instructions -- can refer to
    metadata through a bridge called `MetadataAsValue`.  This is a
    subclass of `Value` where `getType()->isMetadataTy()`.

    `MetadataAsValue` is the *only* class that can legally refer to a
    `LocalAsMetadata`, which is a bridged form of non-`Constant` values
    like `Argument` and `Instruction`.  It can also refer to any other
    `Metadata` subclass.

(I'll break all your testcases in a follow-up commit, when I propagate
this change to assembly.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223802 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-09 18:38:53 +00:00
Eric Christopher
7a76d76e0c These two calls were grabbing the same register info. Unify them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223502 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 19:23:55 +00:00
Adrian Prantl
74fb019dd0 Cleanup: Calls to getDwarfRegNum() may actually fail, if there is
no DWARF register number mapping, or if the register was a virtual
register that was never materialized. Previously, we would just emit a
bogus location, after this patch we don't emit a location at all by
doing an early exit.

After my bugfix in r223401 today, this doesn't actually happen on any
target that I tested this with, but it's still preferable to make the
possibility of a failure explicit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223428 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 01:02:46 +00:00
Peter Collingbourne
bb660fc192 Prologue support
Patch by Ben Gamari!

This redefines the `prefix` attribute introduced previously and
introduces a `prologue` attribute.  There are a two primary usecases
that these attributes aim to serve,

  1. Function prologue sigils

  2. Function hot-patching: Enable the user to insert `nop` operations
     at the beginning of the function which can later be safely replaced
     with a call to some instrumentation facility

  3. Runtime metadata: Allow a compiler to insert data for use by the
     runtime during execution. GHC is one example of a compiler that
     needs this functionality for its tables-next-to-code functionality.

Previously `prefix` served cases (1) and (2) quite well by allowing the user
to introduce arbitrary data at the entrypoint but before the function
body. Case (3), however, was poorly handled by this approach as it
required that prefix data was valid executable code.

Here we redefine the notion of prefix data to instead be data which
occurs immediately before the function entrypoint (i.e. the symbol
address). Since prefix data now occurs before the function entrypoint,
there is no need for the data to be valid code.

The previous notion of prefix data now goes under the name "prologue
data" to emphasize its duality with the function epilogue.

The intention here is to handle cases (1) and (2) with prologue data and
case (3) with prefix data.

References
----------

This idea arose out of discussions[1] with Reid Kleckner in response to a
proposal to introduce the notion of symbol offsets to enable handling of
case (3).

[1] http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-May/073235.html

Test Plan: testsuite

Differential Revision: http://reviews.llvm.org/D6454

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223189 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-03 02:08:38 +00:00
Manman Ren
b179c6a5e5 Debug Info: revert r222195, r222210 and r222239.
This is no longer needed after David's fix at r222377 + r222485.
rdar://18958417


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222563 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-21 19:55:23 +00:00
David Blaikie
5401ba7099 Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool>
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.

This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222334 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-19 07:49:26 +00:00
David Blaikie
1d4f28c6bc Remove StringMap::GetOrCreateValue in favor of StringMap::insert
Having two ways to do this doesn't seem terribly helpful and
consistently using the insert version (which we already has) seems like
it'll make the code easier to understand to anyone working with standard
data structures. (I also updated many references to the Entry's
key and value to use first() and second instead of getKey{Data,Length,}
and get/setValue - for similar consistency)

Also removes the GetOrCreateValue functions so there's less surface area
to StringMap to fix/improve/change/accommodate move semantics, etc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222319 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-19 05:49:42 +00:00
Frederic Riss
60a8349a7d Allow DwarfCompileUnit::constructImportedEntityDIE to instanciate a GlobalVariable DIE.
Usually global variables are in a retain list and instanciated before
any call to constructImportedEntityDIE is made. This isn't true for
forward declarations though.
The testcase for this change is generated by a clang patched to emit
such forward declarations (patch at http://reviews.llvm.org/D6173
which will land soon). The updated testcase tests more than just
global variables, it now tests every type of 'using' clause we
support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222217 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-18 02:46:11 +00:00
Manman Ren
b05098b884 Debug Info: In DIBuilder, the context field of a global variable is updated to
use DIScopeRef.

A paired commit at clang will follow to show cases where we will use an
identifer for the context of a global variable.

rdar://18958417


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222195 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-18 00:29:08 +00:00