Commit Graph

3 Commits

Author SHA1 Message Date
Philip Reames e03301a3b3 [StackMaps] Update llvm-readobj to parse V3 Stackmaps
This updates the StackMap parser in the llvm-readobj tool to parse version 3 StackMaps, which were bumped in https://reviews.llvm.org/D32629.

Version 3 StackMaps differ in that they have a uint16 sized "location size" field which was added to the Location block in a StackMap record. The record has additional padding for alignment. This was a backwards incompatible change resulting in a StackMap version bump.

Patch By: jacob.hughes@kcl.ac.uk (with a rewrite of tests by me)
Differential Revision: https://reviews.llvm.org/D59020

llvm-svn: 358325
2019-04-13 03:55:13 +00:00
Sanjoy Das 23f06e53d8 [Stackmap] Added callsite counts to emitted function information.
Summary:
It was previously not possible for tools to use solely the stackmap
information emitted to reconstruct the return addresses of callsites in
the map, which is necessary to use the information to walk a stack. This
patch adds per-function callsite counts when emitting the stackmap
section in order to resolve the problem. Note that this slightly alters
the stackmap format, so external tools parsing these maps will need to
be updated.

**Problem Details:**
Records only store their offset from the beginning of the function they
belong to. While these records and the functions are output in program
order, it is not possible to determine where the end of one function's
records are without the callsite count when processing the records to
compute return addresses.

Patch by Kavon Farvardin!

Reviewers: atrick, ributzka, sanjoy

Subscribers: nemanjai

Differential Revision: https://reviews.llvm.org/D23487

llvm-svn: 281532
2016-09-14 20:22:03 +00:00
Lang Hames 02f32d93ee [Stackmap] Pre-assemble the stackmap parser test case. (Fix builders).
This case had been failing on testers that didn't have x86 support. Rather
than XFAIL it on testers without x86 support, I've just assembled it and used
the raw object as the test input.

llvm-svn: 240875
2015-06-27 03:49:25 +00:00