This CL combines similar code in amd64's assembly generator. The
total size of pkg/linux_amd64/cmd/compile/ decreases about 4.5KB,
while the generated amd64 code is not affected.
Change-Id: I4cdbdd22bde8857aafdc29b47fa100a906fa1598
Reviewed-on: https://go-review.googlesource.com/c/140298
Run-TryBot: Ben Shi <powerman1st@163.com>
Reviewed-by: Keith Randall <khr@golang.org>
This CL combines similar rules together via regular expression,
while does not impact generated 386 code.
Change-Id: I2b26e7fc6adffa0fa10eeb04a4f3a76ddabc760b
Reviewed-on: https://go-review.googlesource.com/c/140297
Reviewed-by: Keith Randall <khr@golang.org>
This CL combines several rules together via regular expression,
but won't impact generated 386 code.
Change-Id: I354006fe801fc952e3a9431cae63229922c9ba48
Reviewed-on: https://go-review.googlesource.com/c/139957
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The indexed MOVload and MOVstore have similar logic, and this CL
combine them together. The total size of pkg/linux_386/cmd/compile/
decreases about 4KB.
Change-Id: I06236a3542aaa3dfc113c49fe4c69d209e018dfe
Reviewed-on: https://go-review.googlesource.com/c/139958
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
In preparation for followup CL merging TPTR32 and TPTR64, move TPTR32
from the small-types fast path to the generic 64-bit fallback code so
that it's in the same case clause as TPTR64.
This should be safe, but theoretically it could change semantics
because TPTR32 used to always be assumed to be "small", whereas now it
will only be considered small for values less than 1<<31.
This change is done in a separate CL so that it's more easily
identified by git bisection in case it does introduce regressions.
Change-Id: I6c7bb253d4e4d95c530a6e05a1147905674b55ca
Reviewed-on: https://go-review.googlesource.com/c/139517
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The previous CL introduced stack objects. This CL removes the old
ambiguously live liveness analysis. After this CL we're relying
on stack objects exclusively.
Update a bunch of liveness tests to reflect the new world.
Fixes#22350
Change-Id: I739b26e015882231011ce6bc1a7f426049e59f31
Reviewed-on: https://go-review.googlesource.com/c/134156
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Rework how the compiler+runtime handles stack-allocated variables
whose address is taken.
Direct references to such variables work as before. References through
pointers, however, use a new mechanism. The new mechanism is more
precise than the old "ambiguously live" mechanism. It computes liveness
at runtime based on the actual references among objects on the stack.
Each function records all of its address-taken objects in a FUNCDATA.
These are called "stack objects". The runtime then uses that
information while scanning a stack to find all of the stack objects on
a stack. It then does a mark phase on the stack objects, using all the
pointers found on the stack (and ancillary structures, like defer
records) as the root set. Only stack objects which are found to be
live during this mark phase will be scanned and thus retain any heap
objects they point to.
A subsequent CL will remove all the "ambiguously live" logic from
the compiler, so that the stack object tracing will be required.
For this CL, the stack tracing is all redundant with the current
ambiguously live logic.
Update #22350
Change-Id: Ide19f1f71a5b6ec8c4d54f8f66f0e9a98344772f
Reviewed-on: https://go-review.googlesource.com/c/134155
Reviewed-by: Austin Clements <austin@google.com>
This CL removes all unused code from bimport.go and bexport.go.
In the interest of keeping this CL strictly delete-only and easier to
review, the task of consolidating the vestigial code elsewhere is left
to future CLs.
Change-Id: Ib757cc27e3fe814cbf534776d026e4d4cddfc6db
Reviewed-on: https://go-review.googlesource.com/c/139338
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The new indexed package export format appears stable, and no reports
of needing to revert back to binary package export.
This CL disables the binary package export format by mechanically
replacing 'flagiexport' with 'true', and then superficial code
cleanups to keep the resulting code idiomatic. The resulting dead code
is removed in a followup CL.
Change-Id: Ic30d85f78778a31d279a56b9ab14e80836d50135
Reviewed-on: https://go-review.googlesource.com/c/139337
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
In some optimization rules the type of generated OffPtr was
incorrectly set to the type of the pointee, instead of the
pointer. When the OffPtr value is spilled, this may generate
a spill of the wrong type, e.g. a floating point spill of an
integer (pointer) value. On Wasm, this leads to invalid
bytecode.
Fixes#27961.
Change-Id: I5d464847eb900ed90794105c0013a1a7330756cc
Reviewed-on: https://go-review.googlesource.com/c/139257
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
dump/fdump is a reflection-based data structure dumper slightly
customized for the compiler's Node data structure. It dumps the
transitivle closure of Node (and other) data structures using a
recursive descent depth first traversal and permits filtering
options (recursion depth limitation, filtering of struct fields).
I have been using it to diagnose compiler bugs and found it more
useful than the existing node printing code in some cases because
field filtering reduces the output to the interesting parts.
No impact on rest of compiler if functions are not called (which
they only should during a debugging session).
Change-Id: I79d7227f10dd78dbd4bbcdf204db236102fc97a7
Reviewed-on: https://go-review.googlesource.com/136397
Reviewed-by: Alan Donovan <adonovan@google.com>
During a call to a reflect-generated function or method (via
makeFuncStub or methodValueCall), when should we scan the return
values?
When we're starting a reflect call, the space on the stack for the
return values is not initialized yet, as it contains whatever junk was
on the stack of the caller at the time. The return space must not be
scanned during a GC.
When we're finishing a reflect call, the return values are
initialized, and must be scanned during a GC to make sure that any
pointers in the return values are found and their referents retained.
When the GC stack walk comes across a reflect call in progress on the
stack, it needs to know whether to scan the results or not. It doesn't
know the progress of the reflect call, so it can't decide by
itself. The reflect package needs to tell it.
This CL adds another slot in the frame of makeFuncStub and
methodValueCall so we can put a boolean in there which tells the
runtime whether to scan the results or not.
This CL also adds the args length to reflectMethodValue so the
runtime can restrict its scanning to only the args section (not the
results) if the reflect package says the results aren't ready yet.
Do a delicate dance in the reflect package to set the "results are
valid" bit. We need to make sure we set the bit only after we've
copied the results back to the stack. But we must set the bit before
we drop reflect's copy of the results. Otherwise, we might have a
state where (temporarily) no one has a live copy of the results.
That's the state we were observing in issue #27695 before this CL.
The bitmap used by the runtime currently contains only the args.
(Actually, it contains all the bits, but the size is set so we use
only the args portion.) This is safe for early in a reflect call, but
unsafe late in a reflect call. The test issue27695.go demonstrates
this unsafety. We change the bitmap to always include both args
and results, and decide at runtime which portion to use.
issue27695.go only has a test for method calls. Function calls were ok
because there wasn't a safepoint between when reflect dropped its copy
of the return values and when the caller is resumed. This may change
when we introduce safepoints everywhere.
This truncate-to-only-the-args was part of CL 9888 (in 2015). That
part of the CL fixed the problem demonstrated in issue27695b.go but
introduced the problem demonstrated in issue27695.go.
TODO, in another CL: simplify FuncLayout and its test. stack return
value is now identical to frametype.ptrdata + frametype.gcdata.
Fixes#27695
Change-Id: I2d49b34e34a82c6328b34f02610587a291b25c5f
Reviewed-on: https://go-review.googlesource.com/137440
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
The DIEs for global variables were all assigned to the first emitted
compile unit in debug_info, regardless of what it was. Move them
instead to their respective compile units.
Change-Id: If794fa0ba4702f5b959c6e8c16119b16e7ecf6d8
Reviewed-on: https://go-review.googlesource.com/137235
Reviewed-by: Than McIntosh <thanm@google.com>
Show a more specifc error message in the form of "%d variables but %v
returns %d values" if an assignment mismatch occurs with a function
or method call on the right.
Fixes#27595
Change-Id: Ibc97d070662b08f150ac22d686059cf224e012ab
Reviewed-on: https://go-review.googlesource.com/135575
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This change updates the expected output of the gdb debugging session
in the TestNexting internal/ssa test, aligning it with the changes
introduced in CL 134555.
Fixes#27863
Change-Id: I29e747930c7668b429e8936ad230c4d6aa24fdac
Reviewed-on: https://go-review.googlesource.com/137455
Reviewed-by: Than McIntosh <thanm@google.com>
Document what the fields of regalloc mean.
Hopefully will help people understand how the register allocator works.
Change-Id: Ic322ed2019cc839b812740afe8cd2cf0b61da046
Reviewed-on: https://go-review.googlesource.com/137016
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
&^ and << have equal precedence. Add some parentheses to make sure
we shift before we andnot.
Fixes#27829
Change-Id: Iba8576201f0f7c52bf9795aaa75d15d8f9a76811
Reviewed-on: https://go-review.googlesource.com/136899
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Node.copy used to make a shallow copy of a node. Often, this is not
correct: If a node n's Orig field pointed to itself, the copy's Orig
field has to be adjusted to point to the copy. Otherwise, if n is
modified later, the copy's Orig appears modified as well (because it
points to n).
This was fixed for one specific case with
https://go-review.googlesource.com/c/go/+/136395 (issue #26855).
This change instead addresses copy in general:
In two cases we don't want the Orig adjustment as it causes escape
analysis output to fail (not match the existing error messages).
rawcopy is used in those cases.
In several cases Orig is set to the copy immediately after making
a copy; a new function sepcopy is used there.
Updates #26855.
Fixes#27765.
Change-Id: Idaadeb5c4b9a027daabd46a2361348f7a93f2b00
Reviewed-on: https://go-review.googlesource.com/136540
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The ADDconstmodify has similar logic with other constmodify like
instructions. This CL optimize them to share code via fallthrough.
And the size of pkg/linux_386/cmd/compile/internal/x86.a decreases
about 0.3KB.
Change-Id: Ibdf06228afde875e8fe8e30851b50ca2be513dd9
Reviewed-on: https://go-review.googlesource.com/136398
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Found while tracking down #26855.
Change-Id: Ice137fe390820ba351e1c7439b6a9a1b3bdc966b
Reviewed-on: https://go-review.googlesource.com/136396
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
See the change and comment in typecheck.go for a detailed explanation.
Fixes#26855.
Change-Id: I7867f948490fc0873b1bd849048cda6acbc36e76
Reviewed-on: https://go-review.googlesource.com/136395
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Use String and GoString methods instead of the xconf names
for the numeric conversion routines.
Also, fixed a couple of comments in fmt.go.
Change-Id: I1b8acdd95dbff3fc30273070fbb1ac4860031a3c
Reviewed-on: https://go-review.googlesource.com/136197
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The fconv flag arguments were 0, FmtSharp, and FmtSharp|FmtSign.
The 0 value was used for binary representation only, which was
readily available via Mpflt.String. Otherwise, FmtSharp was always
passed. FmtSign was used to print the '+' sign in case of a positive
number and only needed for complex number formatting. Instead
implemented cconv and handled it there.
Change-Id: I1f77282f995be9cfda05efb71a0e027836a9da26
Reviewed-on: https://go-review.googlesource.com/136195
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Since there are no nested loops and/or switches,
loop label can be removed and "bare continue" can be used.
Change-Id: Id642a0859299e4470af544d59884fec51dbb31ee
Reviewed-on: https://go-review.googlesource.com/135837
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Teach samesafeexpr to handle arithmetic unary and binary ops.
It makes map lookup optimization possible in
m[k+1] = append(m[k+1], ...)
m[-k] = append(m[-k], ...)
... etc
Does not cover "+" for strings (concatenation).
Change-Id: Ibbb16ac3faf176958da344be1471b06d7cf33a6c
Reviewed-on: https://go-review.googlesource.com/135795
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
AMD64's ADDQconstmodify/ADDLconstmodify have similar logic with
other constmodify like operators, but seperated case statements.
This CL simplify them with a fallthrough.
Change-Id: Ia73ffeaddc5080182f68c06c9d9b48fe32a14e38
Reviewed-on: https://go-review.googlesource.com/135855
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
That optimization is not valid if x == -0.
The test is a bit tricky because 0 == -0. We distinguish
0 from -0 with 1/0 == inf, 1/-0 == -inf.
This has been a bug since CL 24790 in Go 1.8. Probably doesn't
warrant a backport.
Fixes#27718
Note: the optimization x-0 -> x is actually valid.
But it's probably best to take it out, so as to not confuse readers.
Change-Id: I99f16a93b45f7406ec8053c2dc759a13eba035fa
Reviewed-on: https://go-review.googlesource.com/135701
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Makes use of bounded shift information to generate
more efficient shift instructions.
Updates #25167 for ppc64x
Change-Id: I7fc8d49a3fb3e0f273cc51bc767470b239cbdca7
Reviewed-on: https://go-review.googlesource.com/135380
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
According to AMD64.rules, BTS&BTR&BTC use arg1 as the bit index,
while BT uses arg0. This CL fixes the wrong comment message in
AMD64Ops.go, which indicates all bit indexes are in arg0.
Change-Id: Idb78f4d39f7ef5ea78065ad8bc651324597e2a8a
Reviewed-on: https://go-review.googlesource.com/135419
Reviewed-by: Keith Randall <khr@golang.org>
The CMPconstload opcodes take a ValAndOff as their AuxInt, not just
an offset.
Originally introduced in CL 135379.
Change-Id: I244b2d56ef2e99d2975faa2e97f4291ec97c64b7
Reviewed-on: https://go-review.googlesource.com/135418
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
Use the new custom truncate/extension code when storing or extracting
float32 values from AuxInts to avoid the value being changed by the
host platform's floating point conversion instructions (e.g. sNaN ->
qNaN).
Updates #27516.
Change-Id: Id39650f1431ef74af088c895cf4738ea5fa87974
Reviewed-on: https://go-review.googlesource.com/134855
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Instead of skipping all OSLICEARR, skip only ones with non-pointer
array type. For pointers to arrays, it's safe to apply the
self-assignment slicing optimizations.
Refactored the matching code into separate function for readability.
This is an extension to already existing optimization.
On its own, it does not improve any code under std, but
it opens some new optimization opportunities. One
of them is described in the referenced issue.
Updates #7921
Change-Id: I08ac660d3ef80eb15fd7933fb73cf53ded9333ad
Reviewed-on: https://go-review.googlesource.com/133375
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
