Commit Graph

83 Commits

Author SHA1 Message Date
Alessandro Arzilli
f5d5a681d0
proc: do not assume abstract origins precede their uses (#2293)
The DWARF standard does not say that a DW_ATTR_abstract_origin can only
reference entries that appear before it, this change fixes BinaryInfo
to comply. See #2284 for an example of this happening.
2021-01-27 06:58:48 -08:00
Alessandro Arzilli
6dd686ca49
Go 1.16 support branch (#2214)
* proc: misc test fixes for Go 1.16

* proc: fix cgo stacktraces in Go 1.16 with simplified C -> Go call path

* dwarf/line: make dwarf/line correct when '\\' are used

Our code depends heavily on paths being '/' separated because go always
produced '/' separated file paths. The call to filepath.Join will
normalize the paths, on windows, to always be '\\' separated, which
violated our assumptions.

This didn't use to be a problem because the codepath that calls
filepath.Join was never exercised by executable files produced by Go,
but Go 1.16 started producing debug_line sections that use the
directory table with https://go-review.googlesource.com/c/go/+/263017/.

Fix this to always use path.Join after making sure, on windows, to
always normalize paths to use '/' as a separator. Replace the use of
filepath.IsAbs with an operating system independent version.

* goversion: bump supported Go version
2021-01-05 10:56:30 -08:00
hitzhangjie
d481eabab9
dwarf/*: add godoc comments (#2265) 2020-12-14 09:31:11 -08:00
Andrei Matei
60b5e9d4ba
dwarf/reader: minor comments around variable resolving (#2253)
Fix some stale comments and add some comments that I would have found
useful.
2020-12-08 11:46:40 -08:00
Alessandro Arzilli
34ffa2e763
dwarf/line: do not consider end of sequence entries valid (#2235)
This is needed to fix the problem we have with 1.15.4+ after the
backport is applied to it. The DWARF standard isn't clear on what
should happen with the end_of_sequence opcode but this is consistent
with debug/dwarf.LineReader as well as gdb.
2020-12-04 09:35:57 -08:00
Alessandro Arzilli
2bd38fff90
dwarf/line: ignore end_of_sequence entry if AllPCsBetween (#2180)
* dwarf/line: ignore end_of_sequence entry if AllPCsBetween

Go 1.15 (but possibly prior versions of Go too) has a tendency to use
an address in the middle of an instruction for this entry, but if it
was correct it would be after the last instruction of the function
anyway.

This problem manifests especially frequently as a target crash in
TestStepConcurrentPtr on linux/arm64 (~6% of the runs).

* Travis-CI: add ignorechecksum option to chocolatey command

Looks like a configuration problem on chocolatey's end.

Co-authored-by: a <a@kra>
2020-09-24 08:03:46 -07:00
Alessandro Arzilli
328cf87808
dwarf/loclist,godwarf,proc: support DWARF version 5 loclists and debug_addr (#2097)
Parses and uses the new debug_loclists section added to DWARFv5.
2020-08-17 17:19:46 -07:00
Alessandro Arzilli
f9c8f7f55b
Go 1.15 support (#2011)
* proc: start variable visibility one line after their decl line

In most cases variables shouldn't be visible on their declaration line
because they won't be initialized there.
Function arguments are treated as an exception.

This fix is only applied to programs compiled with Go 1.15 or later as
previous versions of Go did not report the correct declaration line for
variables captured by closures.

Fixes #1134

* proc: silence go vet error

* Makefile: enable PIE tests on windows/Go 1.15

* core: support core files for PIEs on windows

* goversion: add Go 1.15 to supported versions

* proc: fix function call injection for Go 1.15

Go 1.15 changed the call injection protocol so that the runtime will
execute the injected call on a different (new) goroutine.

This commit changes the function call support in delve to:

1. correctly track down the call injection state after the runtime
   switches to a different goroutine.
2. correctly perform the escapeCheck when stack values can come from
   multiple goroutine stacks.

* proc: miscellaneous fixed for call injection under macOS with go 1.15

- create copy of SP in debugCallAXCompleteCall case because the code
  used to assume that regs doesn't change
- fix automatic address calculation for function arguments when an
  argument has a spurious DW_OP_piece at entry
2020-07-28 09:19:51 -07:00
Alessandro Arzilli
4e83473154
dwarf/line: support DWARF version 5 (#2090)
DWARFv5 has a new format for the header, directory table and line table
of the debug_line section.
2020-07-21 13:39:09 -07:00
Alessandro Arzilli
8571fddbc1
godwarf: handle unsupported types gracefully (#2106)
Backport https://go-review.googlesource.com/c/go/+/158797 from upstream.

Fixes #2101
2020-07-15 10:09:28 -07:00
Alessandro Arzilli
9881edaa99
vendor: remove github.com/pkg/profile dependency (#2053)
It is only used in benchmarks and 'go test' now has command line
options to enable profiling as appropriate (but maybe it didn't in
2014).
2020-05-14 10:16:09 -07:00
Alessandro Arzilli
200994bc8f
proc/*: only load floating point registers when needed (#1981)
Changes implementations of proc.Registers interface and the
op.DwarfRegisters struct so that floating point registers can be loaded
only when they are needed.
Removes the floatingPoint parameter from proc.Thread.Registers.
This accomplishes three things:

1. it simplifies the proc.Thread.Registers interface
2. it makes it impossible to accidentally create a broken set of saved
   registers or of op.DwarfRegisters by accidentally calling
   Registers(false)
3. it improves general performance of Delve by avoiding to load
   floating point registers as much as possible

Floating point registers are loaded under two circumstances:

1. When the Slice method is called with floatingPoint == true
2. When the Copy method is called

Benchmark before:

BenchmarkConditionalBreakpoints-4   	       1	4327350142 ns/op

Benchmark after:

BenchmarkConditionalBreakpoints-4   	       1	3852642917 ns/op

Updates #1549
2020-05-13 11:56:50 -07:00
aarzilli
96890bbe1e dwarf/op: return register values when they are the only piece
When there is a single piece and it's a register value just return it.
This is important for clang compiled programs which will use DW_OP_regN
to specify the value of the frame base.
2020-05-01 11:11:51 -07:00
Alessandro Arzilli
c3a4d726e2
Miscellaneous debug_line improvements (#1999)
* dwarf/line: implement DW_LNE_set_discriminator

We don't use the discriminator field in any way but we need to at least
parse it to support debub_line programs that use it.

* dwarf/line: support parsing DWARF4 debug_line sections

There is an extra field maximum_operations_per_instruction that is used
for VLIW CPUs. We don't support this feature but we have to at least
parse the field to not crash.
2020-04-09 13:57:44 -07:00
aarzilli
3c8d4d52b8 *: un-export unnecessarily public symbols 2020-03-31 14:47:29 -07:00
Derek Parker
85c34e47ee *: mv scripts _scripts
Instead of selectively excluding this directory, hide it from the go
tooling by applying the "_" prefix.
2020-03-28 20:28:51 +01:00
Derek Parker
5d109cb197 *: Add some more documentation to exported types and methods 2020-03-28 19:14:58 +01:00
Alessandro Arzilli
7cd12c34fd
proc,dwarf: cache debug.Entry objects (#1931)
Instead of rescanning debug_info every time we want to read a function
(either to find inlined calls or its variables) cache the tree of
dwarf.Entry that we would generate and use that.

Benchmark before:

BenchmarkConditionalBreakpoints-4   	       1	5164689165 ns/op

Benchmark after:

BenchmarkConditionalBreakpoints-4   	       1	4817425836 ns/op

Updates #1549
2020-03-20 10:23:10 -07:00
Derek Parker
ad75f78c4e
*: Fix go vet complaints (#1935)
* *: Fix go vet struct complaints

* *: Fix struct vet issue on linux

* *: Ignore proc/native in go vet check

We have to do some unsafe pointer manipulation that will never make go
vet happy within the proc/native package. Ignore it for runs of go vet.
2020-03-18 09:25:32 -07:00
chainhelen
f3a191cd73
pkg/proc,service: support linux/386 (#1884)
Implement debugging function for 386 on linux with reference to AMD64.
There are a few remaining problems that need to be solved in another time.

1. The stacktrace of cgo are not exactly as expected.
2. Not implement `core` for now.
3. Not implement `call` for now. Can't not find `runtime·debugCallV1` or
   similar function in $GOROOT/src/runtime/asm_386.s.

Update #20
2020-03-10 09:34:40 -07:00
Alessandro Arzilli
14733084a8
dwarf/line: fix TestDebugLinePrologueParser test for Go 1.14 (#1891)
Go 1.14 has more fake file names, apparently (also go fmt).
2020-02-26 20:38:31 -08:00
Klemens Morgenstern
17f2fa7908
dwarf/line: Fixed DirIdx (index starts at one) (#1873)
* Fixed DirIdx (index starts at one)

I am using the elf to load C++ based elf and there the index starts at one and not zero, hence the minor fix.

* Added test

* Added proper test for c-generated elf & replaced index offset by adding build dir

* Changed other IncludeDir test

* Format fix & replace print with actual test

* Format fixes @derekparker requested.
2020-02-21 09:00:34 -08:00
Alessandro Arzilli
0741d3e57f
*: Go 1.14 support branch (#1727)
* tests: misc test fixes for go1.14

- math.go is now ambiguous due to changes to the go runtime so specify
  that we mean our own math.go in _fixtures
- go list -m requires vendor-mode to be disabled so pass '-mod=' to it
  in case user has GOFLAGS=-mod=vendor
- update version of go/packages, required to work with go 1.14 (and
  executed go mod vendor)
- Increased goroutine migration in one development version of Go 1.14
  revealed a problem with TestCheckpoints in command_test.go and
  rr_test.go. The tests were always wrong because Restart(checkpoint)
  doesn't change the current thread but we can't assume that when the
  checkpoint was taken the current goroutine was running on the same
  thread.

* goversion: update maximum supported version

* Makefile: disable testing lldb-server backend on linux with Go 1.14

There seems to be some incompatibility with lldb-server version 6.0.0
on linux and Go 1.14.

* proc/gdbserial: better handling of signals

- if multiple signals are received simultaneously propagate all of them to the
  target threads instead of only one.
- debugserver will drop an interrupt request if a target thread simultaneously
  receives a signal, handle this situation.

* dwarf/line: normalize backslashes for windows executables

Starting with Go 1.14 the compiler sometimes emits backslashes as well
as forward slashes in debug_line, normalize everything to / for
conformity with the behavior of previous versions.

* proc/native: partial support for Windows async preempt mechanism

See https://github.com/golang/go/issues/36494 for a description of why
full support for 1.14 under windows is problematic.

* proc/native: disable Go 1.14 async preemption on Windows

See https://github.com/golang/go/issues/36494
2020-02-10 17:31:54 -08:00
aarzilli
7eddfb77b9 dwarf/reader: precalcStack does not need to read past the first entry
It was reading all the way to the end of the debug_info section,
slowing down stacktraces substantially.

Benchmark before:

BenchmarkConditionalBreakpoints-4   	       1	80344642562 ns/op

Benchmark after:

BenchmarkConditionalBreakpoints-4   	       1	22218288218 ns/op

i.e. a reduction of the cost of a breakpoint hit from 8ms to 2.2ms

Updates #1549
2020-01-28 11:32:53 +01:00
hengwu0
3f7571ec30 proc: implement stacktrace of arm64 (#1780)
* proc: separate amd64-arch code

separate amd64 code about stacktrace, so we can add arm64 stacktrace code.

* proc: implemente stacktrace of arm64

* delve now can use stack, frame commands on arm64-arch debug.

Co-authored-by: tykcd996 <tang.yuke@zte.com.cn>
Co-authored-by: hengwu0 <wu.heng@zte.com.cn>

* test: remove skip-code of stacktrace on arm64

* add LR DWARF register and remove skip-code for fixed tests

* proc: fix the Continue command after the hardcoded breakpoint on arm64

Arm64 use hardware breakpoint, and it will not set PC to the next instruction like amd64. We should move PC in both runtime.breakpoints and hardcoded breakpoints(probably cgo).

* proc: implement cgo stacktrace on arm64

* proc: combine amd64_stack.go and arm64_stack.go file

* proc: reorganize the stacktrace code

* move SwitchStack function arch-related
* fix Continue command after manual stop on arm64
* add timeout flag to make.go to enable infinite timeouts

Co-authored-by: aarzilli <alessandro.arzilli@gmail.com>
Co-authored-by: hengwu0 <wu.heng@zte.com.cn>

Co-authored-by: tykcd996 <56993522+tykcd996@users.noreply.github.com>
Co-authored-by: Alessandro Arzilli <alessandro.arzilli@gmail.com>
2020-01-21 09:11:20 -08:00
aarzilli
adb1746c60 proc: fix inlined stack reading for midstack inlined calls
Due to a bug in the Go compiler midstack inlined calls do not report
their ranges correctly. We can't check if an address is in the range of
a DIE by simply looking at that DIE's range, we should also recursively
check the DIE's children's ranges.

Also fixes the way stacktraces of midstack inlined calls are reported
(they used to be inverted, with the deepest inlined stack frame
reported last).

Fixes #1795
2020-01-10 09:04:48 +01:00
aarzilli
a8606afb0b proc,service: return build informations for each package
Adds an API call that returns a list of packages contained in the
program and the files that were used to build them, and also a best
guess at which filesystem directory contained the package when it was
built.

This can be used by IDEs to map file paths if the debugging environment
doesn't match the build environment exactly.
2020-01-09 20:19:02 +01:00
aarzilli
0e0d689246 dwarf/line: make LineToPCIn behave like LineToPC for lines without stmt
When a line has instructions associated but none of them have is_stmt
set LineToPC and LineToPCIn should behave in the same way.

Fixes #1817
2020-01-09 09:41:44 -08:00
Alessandro Arzilli
151de14d08 proc: support DW_AT_go_package_name (#1757)
Use the name specified by compile unit attribute DW_AT_go_package_name,
introduced in Go 1.13, to map package names to package paths, instead of
trying to deduce it from names of types.
Also use this mapping for resolving global variables and function
expressions.
2019-11-25 09:10:18 -08:00
Derek Parker
c902522a8c pkg/proc,pkg/dwarf: Introduce loclist package
Move the loclist code out of proc and into its own package in
`pkg/dwarf`.
2019-11-13 18:30:21 +01:00
Alessandro Arzilli
222deeec36 proc,debugger: implement logical breakpoints (#1717)
Modifies FindFileLocation, FindFunctionLocation and LineToPC as well as
service/debugger to support inlining and introduces the concept of
logical breakpoints.

For inlined functions FindFileLocation, FindFunctionLocation and
LineToPC will now return one PC address for each inlining and one PC
for the concrete implementation of the function (if present).

A proc.Breakpoint will continue to represent a physical breakpoint, at
a single memory location.

Breakpoints returned by service/debugger, however, will represent
logical breakpoints and may be associated with multiple memory
locations and, therefore, multiple proc.Breakpoints.

The necessary logic is introduced in service/debugger so that a change
to a logical breakpoint will be mirrored to all its physical
breakpoints and physical breakpoints are aggregated into a single
logical breakpoint when returned.
2019-11-01 12:41:06 -07:00
Alessandro Arzilli
45fb477379 proc: better handling of bad DW_TAG_inlined_subroutine without debug_line (#1722)
Avoid crashing with nil pointer dereference, signal error instead.

Fixes #1720
2019-10-21 10:43:03 -07:00
Alessandro Arzilli
fb3941324b dwarf/line: fix state machine behavior with multi-sequence units (#1681)
A compile unit can produce a debug_line program consisting of multiple
sequences according to the DWARF standard. The standard guarantees that
addresses monotonically increment within a single sequence but
different sequences may not follow this rule.

This commit changes dwarf/line (in particular PCToLine and
AllPCsBetween) to support debug_line sections containing units with
multiple sequences.

TestPCToLine needs to be changed so that it picks valid addresses (i.e.
addresses covered by a sequence) as values for basePC, instead of just
rounding.

Fixes #1694
2019-10-07 09:54:32 -07:00
Alessandro Arzilli
4905cff3c8 proc: allow calls to optimized functions (#1684)
Trust argument order to determine argument frame layout when calling
functions, this allows calling optimized functions and removes the
special cases for runtime.mallocgc.

Fixes #1589
2019-09-25 10:23:02 -07:00
chainhelen
69e6b613d8 pkg/dwarf/frame/parser: Fix parse augmentation (#1679)
According to the description of "CIE: length, CIE_id, version, augmentation"
in Page 122 of  http://dwarfstd.org/doc/Dwarf3.pdf ,
`augmentation` should exclude `version`
2019-09-04 09:02:24 -07:00
Alessandro Arzilli
0c36cfb9b1 dwarf/line: implement missing DW_LNS_set_isa opcode (#1676) 2019-08-27 14:27:14 -07:00
David Chase
ecc62a0f3a dwarf/line: add some detail to unknown opcode messages (#1662) 2019-08-12 15:10:01 -07:00
Derek Parker
f4eaad69d9
*: Add .cirrus.yml for FreeBSD testing (#1639)
* *: Add .cirrus.yml for FreeBSD testing

* *: run go mod tidy

* service/test: prefer 127.0.0.1 over localhost

* dwarf/line: fix TestDebugLinePrologueParser

* vendor: rerun go mod vendor
2019-07-30 08:38:25 -07:00
Alessandro Arzilli
b65882a588 proc: ignore DW_TAG_inlined_subroutine entries without abstract origin (#1637)
GCC produces DW_TAG_inlined_subroutine entries without a
DW_AT_abstract_origin attribute.
From the bug report:

 <1><1fe6c7c>: Abbrev Number: 41 (DW_TAG_subprogram)
    <1fe6c7d>   DW_AT_external    : 1
    <1fe6c7d>   DW_AT_name        : (indirect string, offset: 0x485814): MultiGetImpl
    (omissis)
 <2><1fe6c9e>: Abbrev Number: 65 (DW_TAG_inlined_subroutine)
    <1fe6c9f>   DW_AT_low_pc      : 0x311023a
    <1fe6ca7>   DW_AT_high_pc     : 0x5
    <1fe6caf>   DW_AT_call_file   : 10
    <1fe6cb0>   DW_AT_call_line   : 1690
 <2><1fe6cb2>: Abbrev Number: 20 (DW_TAG_inlined_subroutine)
    <1fe6cb3>   DW_AT_abstract_origin: <0x1ffb534>
    <1fe6cb7>   DW_AT_entry_pc    : 0x311023f
    <1fe6cbf>   DW_AT_ranges      : 0xe9bf20
    <1fe6cc3>   DW_AT_call_file   : 10
    <1fe6cc4>   DW_AT_call_line   : 1690

Inlined subroutine at 1fe6c9e doesn't have abstract origin, a name or a
declaration location. It's unclear whether this is in-standard and what
it even means.

Let's ignore it.

Fixes #1636
2019-07-26 11:24:35 -07:00
Alessandro Arzilli
a8b8f30d39 godwarf: support recursive types involving C qualifiers and typedefs (#1603)
Backports debug/dwarf commit: 535741a69a1300d1fe2800778b99c8a1b75d7fdd
CL: https://go-review.googlesource.com/18459

The x/debug/dwarf that we used for dwarf/godwarf/type.go was forked
from debug/dwarf long before this commit.

Original description:

    Currently readType simultaneously constructs a type graph and resolves
    the sizes of the types. However, these two operations are
    fundamentally at odds: the order we parse a cyclic structure in may be
    different than the order we need to resolve type sizes in. As a
    result, it's possible that when readType attempts to resolve the size
    of a typedef, it may dereference a nil Type field of another typedef
    retrieved from the type cache that's only partially constructed.

    To fix this, we delay resolving typedef sizes until the end of the
    readType recursion, when the full type graph is constructed.

Fixes #1601
2019-07-08 10:24:56 -07:00
David Chase
a25d2a2b24 proc: added *BinaryInfo.AllPCsForFileLine for faster bulk queries (#1592)
Support for bulk queries makes the DWARF quality checker
(github.com/dr2chase/dwarf-goodness/cmd/dwarf-goodness)
run much more efficiently (replace quadratic cost with
linear).
2019-06-27 19:39:15 -07:00
Alessandro Arzilli
a7c2d837d5 proc: add LocationCover method to BinaryInfo (#1573)
Also fixes findCompileUnitForOffset which was broken in some edge cases
(when looking up an offset inside the last child of the compilation
unit) which don't happen in normal executables (we only look up types, and those
are always direct childs of compile units).
2019-06-24 08:02:14 -07:00
Alessandro Arzilli
79ad269bbb proc: support setting string values when it requires an allocation (#1548)
Allow changing the value of a string variable to a new literal string,
which requires calling runtime.mallocgc to allocate the string into the
target process.

This means that a command like:

    call f("some string")

is now supported.

Additionally the command:

    call s = "some string"

is also supported.

Fixes #826
2019-06-17 09:51:29 -07:00
Alessandro Arzilli
1a75095286 godwarf: fix nil pointer reading recursive types involving an array (#1582)
Fixes #1578
2019-06-12 17:35:00 -07:00
Alessandro Arzilli
f3b149bda7 proc: support debugging plugins (#1414)
This change splits the BinaryInfo object into a slice of Image objects
containing information about the base executable and each loaded shared
library (note: go plugins are shared libraries).

Delve backens are supposed to call BinaryInfo.AddImage whenever they
detect that a new shared library has been loaded.

Member fields of BinaryInfo that are used to speed up access to dwarf
(Functions, packageVars, consts, etc...) remain part of BinaryInfo and
are updated to reference the correct image object. This simplifies this
change.

This approach has a few shortcomings:

1. Multiple shared libraries can define functions or globals with the
   same name and we have no way to disambiguate between them.

2. We don't have a way to handle library unloading.

Both of those affect C shared libraries much more than they affect go
plugins. Go plugins can't be unloaded at all and a lot of name
collisions are prevented by import paths.

There's only one problem that is concerning: if two plugins both import
the same package they will end up with multiple definition for the same
function.
For example if two plugins use fmt.Printf the final in-memory image
(and therefore our BinaryInfo object) will end up with two copies of
fmt.Printf at different memory addresses. If a user types
  break fmt.Printf
a breakpoint should be created at *both* locations.
Allowing this is a relatively complex change that should be done in a
different PR than this.

For this reason I consider this approach an acceptable and sustainable
stopgap.

Updates #865
2019-05-08 14:06:38 -07:00
aarzilli
7e86d6749f dwarf/godwarf: tolerate cyclical type DIEs
As specified in line dwarf/godwarf/type.go:507 the typeCache entry
should always be set before recursive calls to readType to avoid infite
recursion.
Most code in readType already does this but some of the code added
later to handle Go types was wrong.
Fix this bug and also fix the String and Size methods of Type so that
they handle recursive types "correctly" (i.e. they don't recur
forever).

No test is added for this since all legitimate uses of cyclical types
were already handled correctly and the malformed types emitted by the
go compiler will probably be removed in 1.12.
See: https://github.com/golang/go/issues/29264

Fixes #1444
2019-01-04 14:52:28 -08:00
Derek Parker
4c9a72e486 *: Update import name to github.com/go-delve/delve
The repository is being switched from the personal account
github.com/derekparker/delve to the organization account
github.com/go-delve/delve. This patch updates imports and docs, while
preserving things which should not be changed such as my name in the
CHANGELOG and in TODO comments.
2019-01-04 19:43:13 +01:00
aarzilli
53957e9f4d proc: do not panic if we can't satisfy a composite location for a slice var
The fix in 7f53117 for Issue #1416 had a bug, fix it and add a test.

Fixes #1419
2018-11-26 11:05:00 -08:00
Derek Parker
810b22a633 pkg/dwarf: Remove exec bit from reader.go
For some reason the Go file pkg/dwarf/reader/reader.go had the exec bit
set on it. This patch removes that.
2018-11-01 06:44:16 +01:00
aarzilli
d2904322fa proc: add flag to disable escape checking in function calls
Fix escape checking in function calls  and add a flag to disable it.
2018-10-15 09:31:35 -07:00