Summary:
1) Make sure to discard dangling debug info if the variable (or
variable fragment) is mapped to something new before we had a
chance to resolve the dangling debug info.
2) When resolving debug info, make sure to bump the associated
SDNodeOrder to ensure that the DBG_VALUE is emitted after the
instruction that defines the value used in the DBG_VALUE.
This will avoid a debug-use before def scenario as seen in
https://bugs.llvm.org/show_bug.cgi?id=36417.
The new test case, test/DebugInfo/X86/sdag-dangling-dbgvalue.ll,
show some other limitations in how dangling debug info is
handled in the SelectionDAG. Since we currently only support
having one dangling dbg.value per Value, we will end up dropping
debug info when there are more than one variable that is described
by the same "dangling value".
Reviewers: aprantl
Reviewed By: aprantl
Subscribers: aprantl, eraman, llvm-commits, JDevlieghere
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D44369
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327303 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Hopefully this also clarifies exactly when and why we're rewriting
certiain S_LOCALs using reference types: We're using the reference type
to stand in for a zero-offset load.
Reviewers: inglorion
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D37309
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312247 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
DbgVariableLocation::extractFromMachineInstruction originally
returned a boolean indicating success. This change makes it return
an Optional<DbgVariableLocation> so we cannot try to access the fields
of the struct if they aren't valid.
Reviewers: aprantl, rnk, zturner
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D37279
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312143 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Some variables show up in Visual Studio as "optimized out" even in -O0
-Od builds. This change fixes two issues that would cause this to
happen. The first issue is that not all DIExpressions we generate were
recognized by the CodeView writer. This has been addressed by adding
support for DW_OP_constu, DW_OP_minus, and DW_OP_plus. The second
issue is that we had no way to encode DW_OP_deref in CodeView. We get
around that by changinge the type we encode in the debug info to be
a reference to the type in the source code.
This fixes PR34261.
The reland adds two extra checks to the original: It checks if the
DbgVariableLocation is valid before checking any of its fields, and
it only emits ranges with nonzero registers.
Reviewers: aprantl, rnk, zturner
Reviewed By: rnk
Subscribers: mgorny, llvm-commits, aprantl, hiraditya
Differential Revision: https://reviews.llvm.org/D36907
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312034 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Some variables show up in Visual Studio as "optimized out" even in -O0
-Od builds. This change fixes two issues that would cause this to
happen. The first issue is that not all DIExpressions we generate were
recognized by the CodeView writer. This has been addressed by adding
support for DW_OP_constu, DW_OP_minus, and DW_OP_plus. The second
issue is that we had no way to encode DW_OP_deref in CodeView. We get
around that by changinge the type we encode in the debug info to be
a reference to the type in the source code.
This fixes PR34261.
Reviewers: aprantl, rnk, zturner
Reviewed By: rnk
Subscribers: mgorny, llvm-commits, aprantl, hiraditya
Differential Revision: https://reviews.llvm.org/D36907
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311957 91177308-0d34-0410-b5e6-96231b3b80d8
DWARF specifies that "line 0" really means "no appropriate source
location" in the line table. By default, use this for branch targets
and some other cases that have no specified source location, to
prevent inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).
Updated patch allows enabling or suppressing this behavior for all
unspecified source locations.
Differential Revision: http://reviews.llvm.org/D24180
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289468 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288683 91177308-0d34-0410-b5e6-96231b3b80d8
The LLDB tests are now ready for this patch.
DWARF specifies that "line 0" really means "no appropriate source
location" in the line table. Use this for branch targets and some
other cases that have no specified source location, to prevent
inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).
Differential Revision: http://reviews.llvm.org/D24180
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288283 91177308-0d34-0410-b5e6-96231b3b80d8
DWARF specifies that "line 0" really means "no appropriate source
location" in the line table. Use this for branch targets and some
other cases that have no specified source location, to prevent
inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).
Differential Revision: http://reviews.llvm.org/D24180
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288212 91177308-0d34-0410-b5e6-96231b3b80d8
Added support for:
1. Multi dimension array.
2. Array of structure type, which previously was declared incompletely.
3. Dynamic size array.
4. Array where element type is a typedef, volatile or constant (this should resolve PR28311).
Differential Revision: http://reviews.llvm.org/D21526
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275167 91177308-0d34-0410-b5e6-96231b3b80d8
If a class has hidden visibility all derived classes and all classes
that have it as a member must have hidden visibility too. That may
be fixable here but requires changes to quite a lot of debug info
classes.
This is also one of the things that GCC enforces aggressively while
clang ignores it, making testing more annoying than necessary.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260529 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Refactor common value, scope, and label tracking logic out of DwarfDebug
into a common base class called DebugHandlerBase.
Update an old LLVM IR test case to avoid an assertion in LexicalScopes.
Reviewers: dblaikie, majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16931
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260432 91177308-0d34-0410-b5e6-96231b3b80d8