Replace int variables with 0/1 as only possible values with bools,
where possible.
Change-Id: I958c082e703bbc1540309da3e17612fc8e247932
Reviewed-on: https://go-review.googlesource.com/105036
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
In gdb, "b f" gets confused if the first instruction of "f"
is not marked as a statement in the DWARF line table.
To ensure gdb is not confused, move the first statement
marker in "f" to its first instruction.
The screwy-looking conditional for "what's the first
instruction with a statement marker" will become simpler in
the future.
Fixes#24695.
Change-Id: I2eef81676b64d1bd9bff5da03b89b9dc0c18f44f
Reviewed-on: https://go-review.googlesource.com/104955
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Method expressions with anonymous receiver types like "struct { T }.m"
require wrapper functions, which we weren't always creating. This in
turn resulted in linker errors.
This CL ensures that we generate wrapper functions for any anonymous
receiver types used in a method expression.
Fixes#22444.
Change-Id: Ia8ac27f238c2898965e57b82a91d959792d2ddd4
Reviewed-on: https://go-review.googlesource.com/105044
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
FreeBSD/Dragonfly and Solaris have identical implementations of
sendFile. Keep one and adjust the comments accordingly.
Change-Id: I77b0f88a4816dd6e40f5cb33919c44606401ac6b
Reviewed-on: https://go-review.googlesource.com/104915
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Although these changes have no essential influence, I think this is a better point.
Change-Id: I571d3a14c948d2fd7bc9561f47f33e9e4c90683f
GitHub-Last-Rev: d8c5d18006
GitHub-Pull-Request: golang/go#24697
Reviewed-on: https://go-review.googlesource.com/104895
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
These rules trigger 190 times during make.bash.
Change-Id: I20d1688db5d8c904a7237c08635c6c9d8bd58b1c
Reviewed-on: https://go-review.googlesource.com/105037
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Updates #22830
Due to not checking if the output slices alias in divLarge,
calls of the form z.div(z, x, y) caused the slice z
to attempt to be used to store both the quotient and the
remainder of the division. CL 78995 applies an alias
check to correct that error. This CL cleans up the
additional div calls that attempt to supply the same slice
to hold both the quotient and remainder.
Note that the call in expNN was responsible for the reported
error in r.Exp(x, 1, m) when r was initialized to a non-zero value.
The second instance in expNNMontgomery did not result in an error
due to the size of the arguments.
// RR = 2**(2*_W*len(m)) mod m
RR := nat(nil).setWord(1)
zz := nat(nil).shl(RR, uint(2*numWords*_W))
_, RR = RR.div(RR, zz, m)
Specifically,
cap(RR) == 5 after setWord(1) due to const e = 4 in z.make(1)
len(zz) == 2*len(m) + 1 after shifting left, numWords = len(m)
Reusing the backing array for z and z2 in div was only triggered if
cap(RR) >= len(zz) + 1 and len(m) > 1 so that divLarge was called.
But, 5 < 2*len(m) + 2 if len(m) > 1, so new arrays were allocated
and the error was never triggered in this case.
Change-Id: Iedac80dbbde13216c94659e84d28f6f4be3aaf24
Reviewed-on: https://go-review.googlesource.com/81055
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
There were multiple ad hoc ways to create method symbols, with subtle
and confusing differences between them. This CL unifies them into a
single well-documented encoding and implementation.
This introduces some inconsequential changes to symbol format for the
sake of simplicity and consistency. Two notable changes:
1) Symbol construction is now insensitive to the package currently
being compiled. Previously, non-exported methods on anonymous types
received different method symbols depending on whether the method was
local or imported.
2) Symbols for method values parenthesized non-pointer receiver types
and non-exported method names, and also always package-qualified
non-exported method names. Now they use the same rules as normal
method symbols.
The methodSym function is also now stricter about rejecting
non-sensical method/receiver combinations. Notably, this means that
typecheckfunc needs to call addmethod to validate the method before
calling declare, which also means we no longer emit errors about
redeclaring bogus methods.
Change-Id: I9501c7a53dd70ef60e5c74603974e5ecc06e2003
Reviewed-on: https://go-review.googlesource.com/104876
Reviewed-by: Robert Griesemer <gri@golang.org>
adjustpointers loops over a bitmap.
If the length of that bitmap is zero,
we can skip making the call entirely.
This speeds up stack copying when there are
no pointers present in either args or locals.
name old time/op new time/op delta
StackCopyPtr-8 101ms ± 4% 90ms ± 4% -10.95% (p=0.000 n=87+93)
StackCopy-8 80.1ms ± 4% 72.6ms ± 4% -9.41% (p=0.000 n=98+100)
StackCopyNoCache-8 121ms ± 3% 113ms ± 3% -6.57% (p=0.000 n=98+97)
Change-Id: I7a272e19bc9a14fa3e3318771ebd082dc6247d25
Reviewed-on: https://go-review.googlesource.com/104737
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This commit does not change the semantics of the Call method. Its
purpose is to avoid duplication of code by making PrepareCall available
for separate use by the wasm backend.
Updates #18892
Change-Id: I04a3098f56ebf0d995791c5375dd4c03b6a202a3
Reviewed-on: https://go-review.googlesource.com/103275
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
OpenBSD's __threxit syscall takes a pointer to a 32-bit value that will be
zeroed immediately before the thread exits. Make use of this instead of
zeroing freeWait from the exitThread assembly and using hacks like switching
to a static stack, so this works on 386.
Change-Id: I3ec5ead82b6496404834d148f713794d5d9da723
Reviewed-on: https://go-review.googlesource.com/105055
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Originally, scalar values were directly stored within interface values
as long as they fit into a pointer-sized slot of memory. And since
interface method calls always pass the full pointer-sized value as the
receiver argument, value-narrowing wrappers were necessary to adapt to
the calling convention for methods with smaller receiver types.
However, for precise garbage collection, we now only store actual
pointers within interface values, so these wrappers are no longer
necessary.
Passes toolstash-check.
Change-Id: I5303bfeb8d0f11db619b5a5d06b37ac898588670
Reviewed-on: https://go-review.googlesource.com/104875
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Mostly replacing C-Style loops with range expressions, but also other
simplifications like the introduction of writeBool and unindenting some
code.
Passes toolstash -cmp on std cmd.
Change-Id: I799bccd4e5d411428dcf122b8588a564a9217e7c
Reviewed-on: https://go-review.googlesource.com/104936
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
VEX constants were used when instructions were added by hand.
Now all VEX-encoded instructions are auto-generated by x86avxgen,
so there is no need for those anymore.
Change-Id: Ida63e5e23a8b819b15f61ac98980dec45a21617c
Reviewed-on: https://go-review.googlesource.com/104775
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Fixes golint receiver name complaints.
We can't go with "a" name as it sometimes is used for obj.Addr args.
Change-Id: I66556f4e3dc42cfaaa4db3ed7772fa6756ea9a9b
Reviewed-on: https://go-review.googlesource.com/104796
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
While at it, also simplify a couple of switches.
Doesn't pass toolstash -cmp on std cmd, because orderBlock(&n2.Nbody) is
moved further down to the n3 loop.
Change-Id: I20a2a6c21eb9a183a59572e0fca401a5041fc40a
Reviewed-on: https://go-review.googlesource.com/104416
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Since it's been reliably failing on one of the linux-arm builders
(arm5spacemonkey) for a long time.
Updates #24221.
Change-Id: I8fccc7e16631de497ccc2c285e510a110a93ad95
Reviewed-on: https://go-review.googlesource.com/104535
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Inl, Inldcl, and InlCost are only applicable to functions with bodies
that can be inlined, so pull them out into a separate Inline type to
make understanding them easier.
A side benefit is that we can check if a function can be inlined by
just checking if n.Func.Inl is non-nil, which simplifies handling of
empty function bodies.
While here, remove some unnecessary Curfn twiddling, and make imported
functions use Inl.Dcl instead of Func.Dcl for consistency for local
functions.
Passes toolstash-check.
Change-Id: Ifd4a80349d85d9e8e4484952b38ec4a63182e81f
Reviewed-on: https://go-review.googlesource.com/104756
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Noticed that we can simply use a []byte slice while investigating
a separate issue. Did the obvious simplification.
Change-Id: I921ebbb42135b5f1a10109236ceb9ae6e94ae7e2
Reviewed-on: https://go-review.googlesource.com/104757
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Stores to auto tmp variables can be hoisted to places
where the line numbers make debugging look "jumpy".
Turning those instructions into ones with is_stmt = 0 in
the DWARF (accomplished by marking ssa nodes with NotStmt)
makes debugging look better while still attributing the
instructions with the correct line number.
The same is true for certain register allocator spills and
reloads.
Change-Id: I97a394eb522d4911cc40b4bf5bf76d3d7221f6c0
Reviewed-on: https://go-review.googlesource.com/98415
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
To improve debugging, instructions should be annotated with
DWARF is_stmt. The DWARF default before was is_stmt=1, and
to remove "jumpy" stepping the optimizer was tagging
instructions with a no-position position, which interferes
with the accuracy of profiling information. This allows
that to be corrected, and also allows more "jumpy" positions
to be annotated with is_stmt=0 (these changes were not made
for 1.10 because of worries about further messing up
profiling).
The is_stmt values are placed in a pc-encoded table and
passed through a symbol derived from the name of the
function and processed in the linker alongside its
processing of each function's pc/line tables.
The only change in binary size is in the .debug_line tables
measured with "objdump -h --section=.debug_line go1.test"
For go1.test, these are 2614 bytes larger,
or 0.72% of the size of .debug_line,
or 0.025% of the file size.
This will increase in proportion to how much the is_stmt
flag is used (toggled).
Change-Id: Ic1f1aeccff44591ad0494d29e1a0202a3c506a7a
Reviewed-on: https://go-review.googlesource.com/93664
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Add IsStmt information to src.lico so that suitable lines
for breakpoints (or not) can be noted, eventually for
communication to the debugger via the linker and DWARF.
The expectation is that the front end will apply statement
boundary marks because it has best information about the
input, and the optimizer will attempt to preserve these.
The exact method for placing these marks is still TBD;
ideally stopping "at" line N in unoptimized code will occur
at a point where none of the side effects of N have occurred
and all of the inputs for line N can still be observed.
The optimizer will work with the same markings supplied
for unoptimized code.
It is a goal that non-optimizing compilation should conserve
statement marks.
The optimizer will also use the not-a-statement annotation
to indicate instructions that have a line number (for
profiling purposes) but should not be the target of
debugger step, next, or breakpoints. Because instructions
marked as statements are sometimes removed, a third value
indicating that a position (instruction) can serve as a
statement if the optimizer removes the current instruction
marked as a statement for the same line. The optimizer
should attempt to conserve statement marks, but it is not
a bug if some are lost.
Includes changes to html output for GOSSAFUNC to indicate
not-default is-a-statement with bold and not-a-statement
with strikethrough.
Change-Id: Ia22c9a682f276e2ca2a4ef7a85d4b6ebf9c62b7f
Reviewed-on: https://go-review.googlesource.com/93663
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
The go/printer (and thus gofmt) uses a heuristic to determine
whether to break alignment between elements of an expression
list which is spread across multiple lines. The heuristic only
kicked in if the entry sizes (character length) was above a
certain threshold (20) and the ratio between the previous and
current entry size was above a certain value (4).
This heuristic worked reasonably most of the time, but also
led to unfortunate breaks in many cases where a single entry
was suddenly much smaller (or larger) then the previous one.
The behavior of gofmt was sufficiently mysterious in some of
these situations that many issues were filed against it.
The simplest solution to address this problem is to remove
the heuristic altogether and have a programmer introduce
empty lines to force different alignments if it improves
readability. The problem with that approach is that the
places where it really matters, very long tables with many
(hundreds, or more) entries, may be machine-generated and
not "post-processed" by a human (e.g., unicode/utf8/tables.go).
If a single one of those entries is overlong, the result
would be that the alignment would force all comments or
values in key:value pairs to be adjusted to that overlong
value, making the table hard to read (e.g., that entry may
not even be visible on screen and all other entries seem
spaced out too wide).
Instead, we opted for a slightly improved heuristic that
behaves much better for "normal", human-written code.
1) The threshold is increased from 20 to 40. This disables
the heuristic for many common cases yet even if the alignment
is not "ideal", 40 is not that many characters per line with
todays screens, making it very likely that the entire line
remains "visible" in an editor.
2) Changed the heuristic to not simply look at the size ratio
between current and previous line, but instead considering the
geometric mean of the sizes of the previous (aligned) lines.
This emphasizes the "overall picture" of the previous lines,
rather than a single one (which might be an outlier).
3) Changed the ratio from 4 to 2.5. Now that we ignore sizes
below 40, a ratio of 4 would mean that a new entry would have
to be 4 times bigger (160) or smaller (10) before alignment
would be broken. A ratio of 2.5 seems more sensible.
Applied updated gofmt to all of src and misc. Also tested
against several former issues that complained about this
and verified that the output for the given examples is
satisfactory (added respective test cases).
Some of the files changed because they were not gofmt-ed
in the first place.
For #644.
For #7335.
For #10392.
(and probably more related issues)
Fixes#22852.
Change-Id: I5e48b3d3b157a5cf2d649833b7297b33f43a6f6e
The trace viewer interprets the slice as a non-terminating
time interval which is quite opposit to what trace records indicate
(i.e., almostly immediately terminating time interval).
As observed in the issue #24663 this can result in quite misleading
visualization of the trace.
Work around the trace viewer's issue by setting a small value
(0.0001usec) as the duration if the time interval is not positive.
Change-Id: I1c2aac135c194d0717f5c01a98ca60ffb14ef45c
Reviewed-on: https://go-review.googlesource.com/104716
Reviewed-by: Heschi Kreinick <heschi@google.com>
This mode is similar to the default traceview mode where the execution
trace is presented in P-oriented way. Each row represents a P, and each
slice represents the time interval of a goroutine's execution on the P.
The difference is that, in this mode, only the execution of goroutines
involved in the specified task is highlighted, and other goroutine
execution or events are greyed out. So, users can focus on how a task is
executed while considering other affecting conditions such as other
goroutines, network events, or process scheduling.
Example: https://user-images.githubusercontent.com/4999471/38116793-a6f995f0-337f-11e8-8de9-88eec2f2c497.png
Here, for a while the program remained idle after the first burst of
activity related to the task because all other goroutines were also
being blocked or waiting for events, or no incoming network traffic
(indicated by the lack of any network activity). This is a bit hard to
discover when the usual task-oriented view (/trace?taskid=<taskid>)
mode.
Also, it simplifies the traceview generation mode logic.
/trace ---> 0
/trace?goid ---> modeGoroutineOriented
/trace?taskid ---> modeGoroutineOriented|modeTaskOriented
/trace?focustask ---> modeTaskOriented
Change-Id: Idcc0ae31b708ddfd19766f4e26ee7efdafecd3a5
Reviewed-on: https://go-review.googlesource.com/103555
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Currently, the runtime falls back to asking for any address the OS can
offer for the heap when it runs out of hint addresses. However, the
race detector assumes the heap lives in [0x00c000000000,
0x00e000000000), and will fail in a non-obvious way if we go outside
this region.
Fix this by actively throwing a useful error if we run out of heap
hints in race mode.
This problem is currently being triggered by TestArenaCollision, which
intentionally triggers this fallback behavior. Fix the test to look
for the new panic message in race mode.
Fixes#24670.
Updates #24133.
Change-Id: I57de6d17a3495dc1f1f84afc382cd18a6efc2bf7
Reviewed-on: https://go-review.googlesource.com/104717
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
On darwin, only writable symbol is exported
(cmd/link/internal/ld/macho.go:/machoShouldExport).
For plugin to work correctly, global variables, including
runtime.framepointer_enabled which is set by the linker, need
to be exported when dynamic linking. Put it in DATA so it is
exported. Also in Go it is defined as a var, which is not
read-only.
While here, do the same for runtime.goarm.
Fixes#24653.
Change-Id: I9d1b7d5a648be17103d20b97be65a901cb69f5a2
Reviewed-on: https://go-review.googlesource.com/104715
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Variables can be declared and shadowing is supported, but modifying
existing variables via assignments was not available.
This meant that modifying a variable from a nested block was not
possible:
{{ $v := "init" }}
{{ if true }}
{{ $v := "changed" }}
{{ end }}
v: {{ $v }} {{/* "init" */}}
Introduce the "=" assignment token, such that one can now do:
{{ $v := "init" }}
{{ if true }}
{{ $v = "changed" }}
{{ end }}
v: {{ $v }} {{/* "changed" */}}
To avoid confusion, rename PipeNode.Decl to PipeNode.Vars, as the
variables may not always be declared after this change. Also change a
few other names to better reflect the added ambiguity of variables in
pipelines.
Modifying the text/template/parse package in a backwards incompatible
manner is acceptable, given that the package godoc clearly states that
it isn't intended for general use. It's the equivalent of an internal
package, back when internal packages didn't exist yet.
To make the changes to the parse package sit well with the cmd/api test,
update except.txt with the changes that we aren't worried about.
Fixes#10608.
Change-Id: I1f83a4297ee093fd45f9993cebb78fc9a9e81295
Reviewed-on: https://go-review.googlesource.com/84480
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
If A's external test package imports B, which imports A, and A's
internal test code adds something to A that invalidates anything in A's
export data, then we need to build B against the test-augmented version
of A before using it to build A's external test package.
https://golang.org/cl/92215 taught 'go test' to do this rebuilding
properly, but 'go vet' was not taught the same trick when it learned to
vet test packages in https://golang.org/cl/87636. This commit moves the
necessary logic into the load.TestPackagesFor function so it can be
shared by 'go test' and 'go vet'.
Fixes#23701.
Change-Id: I1086d447eca02933af53de693384eac99a08d9bd
Reviewed-on: https://go-review.googlesource.com/104315
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
And delete them from asm_test.
Change-Id: Id533130470da9176a401cb94972f626f43a62148
Reviewed-on: https://go-review.googlesource.com/103656
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Add the following helpers in lookup_windows.go:
1) lookupGroupName() is used to obtain the SID of a group based
on name.
2) listGroupsForUsernameAndDomain() uses NetUserGetLocalGroups()
as a WINAPI backend to obtain the list of local groups for this
user.
3) lookupUserPrimaryGroup() is now used to populate the User.Gid
field when looking up a user by name.
Implement listGroups(), lookupGroupId(), lookupGroup() and no longer
return unimplemented errors.
Do not skip Windows User.Gid tests in user_test.go.
Change-Id: I81fd41b406da51f9a4cb24e50d392a333df81141
GitHub-Last-Rev: d1448fd55d
GitHub-Pull-Request: golang/go#24222
Reviewed-on: https://go-review.googlesource.com/98137
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Make the StackCopyNoCache test easier to read.
Add a StackCopyPtr test that actually has some pointers
that need adjusting.
Change-Id: I5b07c26f40cb485c9de97ed63fac89a9e6f36650
Reviewed-on: https://go-review.googlesource.com/104195
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The logic in addBranchRestrictions didn't allow to correctly
model OpIs(Slice)Bound for signed domain, and it was also partly
implemented within addRestrictions.
Thanks to the previous changes, it is now possible to handle
the negative conditions correctly, so that we can learn
both signed/LT + unsigned/LT on the positive side, and
signed/GE + unsigned/GE on the negative side (but only if
the index can be proved to be non-negative).
This is able to prove ~50 more slice accesses in std+cmd.
Change-Id: I9858080dc03b16f85993a55983dbc4b00f8491b0
Reviewed-on: https://go-review.googlesource.com/104037
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>