Commit Graph

10 Commits

Author SHA1 Message Date
Vedant Kumar a459b9f757 Avoid dbg.value use-before-def in a few tests (NFC)
This is preparation for landing a use-before-def verifier for debug
intrinsics (D46100).

As a drive-by, remove `tail` from debug intrinsic calls because it
doesn't mean anything in that context.

llvm-svn: 340366
2018-08-21 23:42:08 +00:00
Reid Kleckner bd5d71229d [codeview] Use push_macro to avoid conflicts instead of a prefix
Summary:
This prefix was added in r333421, and it changed our dumper output to
say things like "CVRegEAX" instead of just "EAX". That's a functional
change that I'd rather avoid.

I tested GCC, Clang, and MSVC, and all of them support #pragma
push_macro. They don't issue warnings whem the macro is not defined
either.

I don't have a Mac so I can't test the real termios.h header, but I
looked at the termios.h sources online and looked for other conflicts.
I saw only the CR* macros, so those are the ones we work around.

Reviewers: zturner, JDevlieghere

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D50851

llvm-svn: 339907
2018-08-16 17:34:31 +00:00
Jonas Devlieghere 43dce3edbe [CodeView] Add prefix to CodeView registers.
Adds CVReg to CodeView register names to prevent a duplicate symbol with
CR3 defined in termios.h, as suggested by Zachary on the mailing list.

http://lists.llvm.org/pipermail/llvm-dev/2018-May/123372.html

Differential revision: https://reviews.llvm.org/D47478

rdar://39863705

llvm-svn: 333421
2018-05-29 14:35:34 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Hans Wennborg ea89ff7c25 CodeView symbol dumper: use symbolic names for registers
https://reviews.llvm.org/D38469

llvm-svn: 314690
2017-10-02 17:44:47 +00:00
Reid Kleckner 8d8888ff42 [codeview] Change readobj symbol dumping format
Avoid duplicating DictScope with hand-written names everywhere.  Print
the S_-prefixed symbol kind for every record. This should make it easier
to search for certain kinds of records when debugging PDB linking.

llvm-svn: 307732
2017-07-11 23:41:41 +00:00
Reid Kleckner b5fced7324 [codeview] Check for a DIExpression offset for local variables
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
2017-05-09 19:59:29 +00:00
Reid Kleckner 3a363fff7e Re-land "Use the frame index side table for byval and inalloca arguments"
This re-lands r302483. It was not the cause of PR32977.

llvm-svn: 302544
2017-05-09 16:02:20 +00:00
Reid Kleckner 9f29914d40 Revert "Use the frame index side table for byval and inalloca arguments"
This reverts r302483 and it's follow up fix.

llvm-svn: 302493
2017-05-09 01:14:39 +00:00
Reid Kleckner 45efcf0c96 Use the frame index side table for byval and inalloca arguments
Summary:
For inalloca functions, this is a very common code pattern:

  %argpack = type <{ i32, i32, i32 }>
  define void @f(%argpack* inalloca %args) {
  entry:
    %a = getelementptr inbounds %argpack, %argpack* %args, i32 0, i32 0
    %b = getelementptr inbounds %argpack, %argpack* %args, i32 0, i32 1
    %c = getelementptr inbounds %argpack, %argpack* %args, i32 0, i32 2
    tail call void @llvm.dbg.declare(metadata i32* %a, ... "a")
    tail call void @llvm.dbg.declare(metadata i32* %c, ... "b")
    tail call void @llvm.dbg.declare(metadata i32* %b, ... "c")

Even though these GEPs can be simplified to a constant offset from EBP
or RSP, we don't do that at -O0, and each GEP is computed into a
register. Registers used to compute argument addresses are typically
spilled and clobbered very quickly after the initial computation, so
live debug variable tracking loses information very quickly if we use
DBG_VALUE instructions.

This change moves processing of dbg.declare between argument lowering
and basic block isel, so that we can ask if an argument has a frame
index or not. If the argument lives in a register as is the case for
byval arguments on some targets, then we don't put it in the side table
and during ISel we emit DBG_VALUE instructions.

Reviewers: aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32980

llvm-svn: 302483
2017-05-08 23:20:27 +00:00