Commit Graph

4 Commits

Author SHA1 Message Date
Reid Kleckner 8a1cd91016 [InstCombine] Add a flag to disable LowerDbgDeclare
Summary:
This should improve optimized debug info for address-taken variables at
the cost of inaccurate debug info in some situations.

We patched this into clang and deployed this change to Chromium
developers, and this significantly improved debuggability of optimized
code. The long-term solution to PR34136 seems more and more like it's
going to take a while, so I would like to commit this change under a
flag so that it can be used as a stop-gap measure.

This flag should really help so for C++ aggregates like std::string and
std::vector, which are typically address-taken, even after inlining, and
cannot be SROA-ed.

Reviewers: aprantl, dblaikie, probinson, dberlin

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D36596

llvm-svn: 313108
2017-09-13 01:43:25 +00:00
Adrian Prantl abe04759a6 Remove the obsolete offset parameter from @llvm.dbg.value
There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.

rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951

llvm-svn: 309426
2017-07-28 20:21:02 +00:00
NAKAMURA Takumi 3c386711f7 llvm/test/Transforms/InstCombine/debuginfo-skip.ll REQUIRES +asserts.
llvm-svn: 303216
2017-05-16 22:19:56 +00:00
Dmitry Mikulin fce148c568 In debug builds non-trivial amount of time is spent in InstCombine processing
@llvm.dbg.* calls in visitCallInst(). They can be safely ignored.

llvm-svn: 303202
2017-05-16 20:08:49 +00:00