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Differential D101086

[lldb] [Process/elf-core] Fix reading FPRs from FreeBSD/i386 cores
ClosedPublic

Authored by mgorny on Apr 22 2021, 10:23 AM.

Details

Reviewers
labath
krytarowski
emaste
Commits
rGb6c0edb9792c: [lldb] [Process/elf-core] Fix reading FPRs from FreeBSD/i386 cores
Summary

The FreeBSD coredumps from i386 systems contain only FSAVE-style
NT_FPREGSET. Since we do not really support reading that kind of data
anymore, just use NT_X86_XSTATE to get FXSAVE-style data when available.

Diff Detail

Event Timeline

mgorny created this revision.Apr 22 2021, 10:23 AM
Herald added subscribers: pengfei, arichardson. · View Herald TranscriptApr 22 2021, 10:23 AM
mgorny requested review of this revision.Apr 22 2021, 10:23 AM
mgorny updated this revision to Diff 339719.Apr 22 2021, 10:46 AM

Also add FPU-specific checks to x86-32-freebsd-addr.test.

Harbormaster completed remote builds in B100321: Diff 339705.Apr 22 2021, 12:53 PM
Harbormaster completed remote builds in B100332: Diff 339719.Apr 22 2021, 1:43 PM
emaste added a comment.May 11 2021, 7:25 AM

LGTM

krytarowski accepted this revision.May 11 2021, 3:25 PM
This revision is now accepted and ready to land.May 11 2021, 3:25 PM
emaste accepted this revision.May 11 2021, 5:57 PM
This revision was landed with ongoing or failed builds.May 12 2021, 2:51 AM
Closed by commit rGb6c0edb9792c: [lldb] [Process/elf-core] Fix reading FPRs from FreeBSD/i386 cores (authored by mgorny). · Explain Why
This revision was automatically updated to reflect the committed changes.
mgorny added a commit: rGb6c0edb9792c: [lldb] [Process/elf-core] Fix reading FPRs from FreeBSD/i386 cores.
Herald added a project: Restricted Project. · View Herald TranscriptMay 12 2021, 2:51 AM

Revision Contents

PathSize
lldb/
source/
Plugins/
Process/
elf-core/
3 lines
test/
Shell/
Register/
Core/
5 lines
3 lines

Diff 344745

lldb/source/Plugins/Process/elf-core/RegisterUtilities.h

Show First 20 Lines • Show All 90 Lines • ▼ Show 20 Lines
// to override a more general entry (e.g. general linux), as long as you place // to override a more general entry (e.g. general linux), as long as you place
// it earlier in the list. If a register set is not found, it returns an empty // it earlier in the list. If a register set is not found, it returns an empty
// DataExtractor. // DataExtractor.
DataExtractor getRegset(llvm::ArrayRef<CoreNote> Notes, DataExtractor getRegset(llvm::ArrayRef<CoreNote> Notes,
const llvm::Triple &Triple, const llvm::Triple &Triple,
llvm::ArrayRef<RegsetDesc> RegsetDescs); llvm::ArrayRef<RegsetDesc> RegsetDescs);
constexpr RegsetDesc FPR_Desc[] = { constexpr RegsetDesc FPR_Desc[] = {
// FreeBSD/i386 core NT_FPREGSET is x87 FSAVE result but the XSAVE dump
// starts with FXSAVE struct, so use that instead if available.
{llvm::Triple::FreeBSD, llvm::Triple::x86, llvm::ELF::NT_X86_XSTATE},
{llvm::Triple::FreeBSD, llvm::Triple::UnknownArch, llvm::ELF::NT_FPREGSET}, {llvm::Triple::FreeBSD, llvm::Triple::UnknownArch, llvm::ELF::NT_FPREGSET},
// In a i386 core file NT_FPREGSET is present, but it's not the result // In a i386 core file NT_FPREGSET is present, but it's not the result
// of the FXSAVE instruction like in 64 bit files. // of the FXSAVE instruction like in 64 bit files.
// The result from FXSAVE is in NT_PRXFPREG for i386 core files // The result from FXSAVE is in NT_PRXFPREG for i386 core files
{llvm::Triple::Linux, llvm::Triple::x86, llvm::ELF::NT_PRXFPREG}, {llvm::Triple::Linux, llvm::Triple::x86, llvm::ELF::NT_PRXFPREG},
{llvm::Triple::Linux, llvm::Triple::UnknownArch, llvm::ELF::NT_FPREGSET}, {llvm::Triple::Linux, llvm::Triple::UnknownArch, llvm::ELF::NT_FPREGSET},
{llvm::Triple::NetBSD, llvm::Triple::aarch64, NETBSD::AARCH64::NT_FPREGS}, {llvm::Triple::NetBSD, llvm::Triple::aarch64, NETBSD::AARCH64::NT_FPREGS},
{llvm::Triple::NetBSD, llvm::Triple::x86_64, NETBSD::AMD64::NT_FPREGS}, {llvm::Triple::NetBSD, llvm::Triple::x86_64, NETBSD::AMD64::NT_FPREGS},
Show All 23 Lines

lldb/test/Shell/Register/Core/x86-32-freebsd-addr.test

# RUN: %lldb -b -s %s -c %p/Inputs/x86-32-freebsd.core | FileCheck %s # RUN: %lldb -b -s %s -c %p/Inputs/x86-32-freebsd.core | FileCheck %s
register read --all register read --all
# CHECK-DAG: eip = 0x00401c6b # CHECK-DAG: eip = 0x00401c6b
# CHECK-DAG: eflags = 0x00010246 # CHECK-DAG: eflags = 0x00010246
# CHECK-DAG: cs = 0x00000033 # CHECK-DAG: cs = 0x00000033
# CHECK-DAG: fs = 0x00000013 # CHECK-DAG: fs = 0x00000013
# CHECK-DAG: gs = 0x0000001b # CHECK-DAG: gs = 0x0000001b
# CHECK-DAG: ss = 0x0000003b # CHECK-DAG: ss = 0x0000003b
# CHECK-DAG: ds = 0x0000003b # CHECK-DAG: ds = 0x0000003b
# CHECK-DAG: es = 0x0000003b # CHECK-DAG: es = 0x0000003b
# TODO: fix reading fp registers # CHECK-DAG: fiseg = 0x00000000
# CHECK-DAG: fioff = 0x00401c52
# CHECK-DAG: foseg = 0x00000000
# CHECK-DAG: fooff = 0xffffd8b8

lldb/test/Shell/Register/Core/x86-32-freebsd-fp.test

  • This file was added.
# RUN: %lldb -b -s %s -c %p/Inputs/x86-32-freebsd.core | FileCheck %p/Inputs/x86-fp.check
register read --all