The point of GOOBJ=2 was to have an active test of the cmd/internal/obj code.
Now we have end-to-end tests of the assembler, and soon the compiler,
so we don't need this halfway test on by default anymore.
(It's still possible to enable during debugging with the
environment variable.)
The problem it causes on the builders is that this particular testing
mode ends up with both the C process and the Go objwriter subprocess
having the same very large Prog list in memory simultaneously,
which causes basically a 2x memory blowup. In large programs
(such as the one generated by test/rotate.go) this is significant.
Disabling GOOBJ=2 should help with the current dev.cc builder
failures.
Change-Id: I1b11e4f29ea575659f02d2234242a904f7c867e4
Reviewed-on: https://go-review.googlesource.com/4832
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Now:
0x0000 00000 (/tmp/x.s:2) MULLU R6,R3,(R7, R6)
The space is a little odd but I'd rather fix the usual printing to add spaces
than delete that one. But in a different CL, once C is gone.
Change-Id: I344e0b06eedaaf53cd79d370fa13c444a1e69c81
Reviewed-on: https://go-review.googlesource.com/4647
Reviewed-by: Rob Pike <r@golang.org>
This isn't everything, but it's a start.
Still producing bit-identical compiler output.
The semantics of the old back ends is preserved,
even when they are probably buggy.
There are some TODOs in gc/gsubr.c to
remove special cases to preserve bugs in 5g and 8g.
Change-Id: I28ae295fbfc94ef9df43e13ab96bd6fc2f194bc4
Reviewed-on: https://go-review.googlesource.com/3802
Reviewed-by: Austin Clements <austin@google.com>
CL 2118 makes the assumption that all references to runtime.tlsg
should be accompanied by a declaration of runtime.tlsg if its type
should be a normal variable, instead of a placeholder for TLS
relocation.
Because if runtime.tlsg is not declared by the runtime package,
the type of runtime.tlsg will be zero, so fix the check in liblink
to look for 0 instead of STLSBSS (the type will be initialized by
cmd/ld, but cmd/ld doesn't run during assembly).
Change-Id: I691ac5c3faea902f8b9a0b963e781b22e7b269a7
Reviewed-on: https://go-review.googlesource.com/4030
Reviewed-by: David Crawshaw <crawshaw@golang.org>
liblink:
- set dummy value for ctxt->tlsoffset.
cmd/ld:
- always do external linking when using cgo on darwin/arm,
as our linker might not generate codesign-compatible binary.
cmd/5l:
- support generate ARM Mach-O binaries
- add machoreloc1() that translate our internal relocation to
macho relocations used by external linking.
Change-Id: Ic5454aeb87009aaf8f1453ec7fe33e6da55d5f06
Reviewed-on: https://go-review.googlesource.com/3273
Reviewed-by: David Crawshaw <crawshaw@golang.org>
In the old code, liblink, cmd/ld and runtime all have code determine
whether runtime.tlsg is an actual variable or a placeholder for TLS
relocation. This change consolidate them into one: the runtime/tls_arm.s
will ultimately determine the type of that variable.
Change-Id: I3b3f80791a1db4c2b7318f81a115972cd2237e43
Reviewed-on: https://go-review.googlesource.com/2118
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
cmd/internal/obj reconverted using rsc.io/c2go rev 2a95256.
- Brings in new, more regular Prog, Addr definitions
- Add Prog* argument to oclass in liblink/asm[68].c, for c2go conversion.
- Update objwriter for change in TEXT size encoding.
- Merge 5a, 6a, 8a, 9a changes into new5a, new6a, new8a, new9a (by hand).
- Add +build ignore to cmd/asm/internal/{addr,arch,asm}, cmd/asm.
They need to be updated for the changes.
- Reenable verifyAsm in cmd/go.
- Reenable GOOBJ=2 mode by default in liblink.
All architectures build successfully again.
Change-Id: I2c845c5d365aa484b570476898171bee657b626d
Reviewed-on: https://go-review.googlesource.com/3963
Reviewed-by: Rob Pike <r@golang.org>
The upcoming merge is going to break the synchrony.
Will restore separately.
Change-Id: I90946119a0901e24063b190d1a074594af7654c7
Reviewed-on: https://go-review.googlesource.com/3888
Reviewed-by: Russ Cox <rsc@golang.org>
Add Addr-checking for all Progs on input to liblink, in liblink/pass.c,
including requiring use of TYPE_ADDR, not TYPE_CONST.
Update compilers and assemblers to satisfy checks.
Change-Id: Idac36b9f6805f0451cb541d2338992ca5eaf3963
Reviewed-on: https://go-review.googlesource.com/3801
Reviewed-by: Austin Clements <austin@google.com>
This makes names like ANOP, ATEXT, AGLOBL, ACALL, AJMP, ARET
available for use by architecture-independent processing passes.
On arm and ppc64, the alternate names are now aliases for the
official ones (ABL for ACALL, AB or ABR for AJMP, ARETURN for ARET).
Change-Id: Id027771243795af2b3745199c645b6e1bedd7d18
Reviewed-on: https://go-review.googlesource.com/3577
Reviewed-by: Aram Hăvărneanu <aram@mgk.ro>
Reviewed-by: Austin Clements <austin@google.com>
Like the TEXT/GLOBL flags, this was split between from.scale and reg,
neither of which is appropriate.
Change-Id: I2a16ef066a53b6edb7afb16cce108c0d1d26389c
Reviewed-on: https://go-review.googlesource.com/3576
Reviewed-by: Aram Hăvărneanu <aram@mgk.ro>
Reviewed-by: Austin Clements <austin@google.com>
Use AXXX instead of AGOK (neither is a valid instruction but AXXX is zero)
for the initial setting of Prog.as, and now there are no non-zero default
field settings.
Remove the arch-specific zprog/zprg in favor of a single global zprog.
Remove the arch-specific prg constructor in favor of emallocz(sizeof(Prog)).
Change-Id: Ia73078726768333d7cdba296f548170c1bea9498
Reviewed-on: https://go-review.googlesource.com/3575
Reviewed-by: Aram Hăvărneanu <aram@mgk.ro>
Reviewed-by: Austin Clements <austin@google.com>
Originally, when this code was part of 6l/8l, every new
Prog was constructed starting with zprg, which set back=2,
and then this code walked over the list setting back=1 for
backward branches, back=0 otherwise. The initial back=2
setting was used to identify forward branches (the branched-to
instruction had back == 2 since it hadn't yet been set to 0 or 1).
When the code was extracted into liblink and linked directly
with 6a/6g/8a/8g, those programs created the Prog struct
and did not set back=2, breaking this backward branch detection.
No one noticed, because the next loop recomputes the information.
The only requirement for the next loop is that p->back == 0 or 1 for
each of the Progs in the list.
The initialization of the zprg with back=2 would cause problems
in this second loop, for the few liblink-internally-generated instructions
that are created by copying zprg, except that the first loop was
making sure that back == 0 or 1.
The first loop's manipulation of p->back can thus be deleted,
provided we also delete the zprg.back = 2 initializations.
This is awful and my fault. I apologize.
While we're here, remove the .scale = 1 from the zprg init too.
Anything that sets up a scaled index should set the scale itself.
(And mostly those come from outside liblink anyway.)
Tested by checking that all generated code is bit-for-bit
identical to before this CL.
Change-Id: I7f6e0b33ce9ccd5b7dc25e0f00429fedd0957c8c
Reviewed-on: https://go-review.googlesource.com/3574
Reviewed-by: Austin Clements <austin@google.com>
A step toward making the zero Prog useful.
Change-Id: I427b98b1ce9bd8f093da825aa4bb83244fc01903
Reviewed-on: https://go-review.googlesource.com/3573
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Austin Clements <austin@google.com>
Before, amd64 and 386 stored the flags in p->from.scale
and arm and ppc64 stored the flags in p->reg.
Both caused special cases in printing and in handling of the
addresses.
To avoid possible conflicts with the real meaning of p->from
and to avoid storing a non-register value in a reg field,
use from3 to hold a TYPE_CONST value giving the flags.
There is still a special case for printing, because the flags
are specified without a $, and normally a TYPE_CONST prints
with a $. But that's much less special than what came before.
This allows us to remove the textflag and settextflag methods
from LinkArch. They are no longer architecture-specific.
Change-Id: I931da8e1ecd92e127cd9aa44ef5a73c42e730110
Reviewed-on: https://go-review.googlesource.com/3572
Reviewed-by: Austin Clements <austin@google.com>
This adds a "framepointer" GOEXPERIMENT that that makes the amd64
toolchain maintain base pointer chains in the same way that gcc
-fno-omit-frame-pointer does. Go doesn't use these saved base
pointers, but this does enable external tools like Linux perf and
VTune to unwind Go stacks when collecting system-wide profiles.
This requires support in the compilers to not clobber BP, support in
liblink for generating the BP-saving function prologue and unwinding
epilogue, and support in the runtime to save BPs across preemption, to
skip saved BPs during stack unwinding and, and to adjust saved BPs
during stack moving.
As with other GOEXPERIMENTs, everything from the toolchain to the
runtime must be compiled with this experiment enabled. To do this,
run make.bash (or all.bash) with GOEXPERIMENT=framepointer.
Change-Id: I4024853beefb9539949e5ca381adfdd9cfada544
Reviewed-on: https://go-review.googlesource.com/2992
Reviewed-by: Russ Cox <rsc@golang.org>
headstr(Hlinux) was reporting "android",
making for some confusing error messages.
Change-Id: I437095bee7cb2143aa37c91cf786f3a3581ae7b9
Reviewed-on: https://go-review.googlesource.com/3513
Reviewed-by: Austin Clements <austin@google.com>
- certain code paths were appending to the string without first clearing it.
- some prints were using spaces instead of tabs
Change-Id: I7a3d38289c8206682baf8942abf5a9950a56b449
Reviewed-on: https://go-review.googlesource.com/3511
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Dave Cheney <dave@cheney.net>
Pointers change from run to run, making it hard to use
the debug output to identify the reason for a changed
object file.
Change-Id: I0c954da0943092c48686afc99ecf75eba516de6a
Reviewed-on: https://go-review.googlesource.com/3352
Reviewed-by: Aram Hăvărneanu <aram@mgk.ro>
Reviewed-by: Rob Pike <r@golang.org>
The argument is unused in the C code but will be used in the Go translation,
because the Prog holds information needed to invoke the right meaning
of %A in the ctxt->diag calls in vaddr.
Change-Id: I501830f8ea0e909aafd8ec9ef5d7338e109d9548
Reviewed-on: https://go-review.googlesource.com/3041
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-on: https://go-review.googlesource.com/3310
Reviewed-by: Russ Cox <rsc@golang.org>
Using rsc.io/c2go repo revision 60c9302.
- Export a few symbols needed by assemblers.
- Implement Getgoroot etc directly, and add Getgoversion.
- Removes dependency on Go 1.4 go/build.
- Change magic history name <no name> to <pop>
The <pop> change requires adjustment to the liblink serializer.
Change-Id: If5fb52ac9e91d50805263070b3fc5cc05d8b7632
Reviewed-on: https://go-review.googlesource.com/3141
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
This CL enables moving the bulk of the object writing code
out of liblink and into translated Go libraries in cmd/internal/obj,
but it does not do the move.
This CL introduces two new environment variables,
$GOOBJ and $GOOBJWRITER, but both will be deleted along with
the rest of the liblink C code.
The default behavior of a build is unchanged by this CL:
the C version of liblink uses the C object layout and writing code.
If $GOOBJ=1, liblink invokes go tool objwriter instead.
If $GOOBJ=2, liblink does its own layout and then invokes
go tool objwriter, which checks that it gets the same answer.
That is, in $GOOBJ=2 mode, both the C and the Go version of
the code run, and the operation fails if the two produce different
answers. This provides a very strong check that the translation
is working correctly.
Change-Id: I56ab49b07ccb2c7b81085f1d6950131047c6aa3c
Reviewed-on: https://go-review.googlesource.com/3048
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Executing 'clean -i std' removes installed Go programs,
including the toolchain binaries we need for building.
It's not clear why the 'clean -i std' is here in the first place.
cmd/dist just removed the entire pkg tree, so everything is new.
The only reason for 'clean -i std' would be if you don't trust
that dist compiled the packages properly. If that's true for
some reason, we can fix cmd/dist, or add -a to the install
commands that follow. Perhaps clean -i std should not
remove tools, or perhaps std should not expand to any tools.
Not sure.
Also remove banner from make.bat and make.rc that was
already removed from make.bash. cmd/dist prints it now.
Also fix array size error in liblink/objfile.c.
Fixes dev.cc build.
Change-Id: I60855e001a682efce55ad9aa307a8f3ee47f7366
Reviewed-on: https://go-review.googlesource.com/3100
Reviewed-by: Russ Cox <rsc@golang.org>
This doesn't actually use objwriter for any real work.
It's just to check that objwriter is available.
The real work will be moved once the bootstrapping
mechanisms are working.
Change-Id: I5f41c8910c4b11b9d80cb0b0847ff9cb582fc2be
Reviewed-on: https://go-review.googlesource.com/3045
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The argument is unused in the C code but will be used in the Go translation,
because the Prog holds information needed to invoke the right meaning
of %A in the ctxt->diag calls in vaddr.
Change-Id: I501830f8ea0e909aafd8ec9ef5d7338e109d9548
Reviewed-on: https://go-review.googlesource.com/3041
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Mostly this is using uint32 instead of int32 for unsigned values
like instruction encodings or float32 bit representations,
removal of ternary operations, and removal of #defines.
Delete sched9.c, because it is not compiled (it is still in the history
if we ever need it).
Change-Id: I68579cfea679438a27a80416727a9af932b088ae
Reviewed-on: https://go-review.googlesource.com/2658
Reviewed-by: Austin Clements <austin@google.com>
This reverts commit ab0535ae3f.
I think it will remain useful to distinguish code that must
run on a system stack from code that can run on either stack,
even if that distinction is no
longer based on the implementation language.
That is, I expect to add a //go:systemstack comment that,
in terms of the old implementation, tells the compiler,
to pretend this function was written in C.
Change-Id: I33d2ebb2f99ae12496484c6ec8ed07233d693275
Reviewed-on: https://go-review.googlesource.com/2275
Reviewed-by: Russ Cox <rsc@golang.org>
liblink used to encode both SETEQ BP and SETEQ CH as 0f 94 c5,
however, SETEQ BP should have used a REX prefix.
Fixes#8545.
Change-Id: Ie59c990cdd0ec506cffe4318e9ad1b48db5e57dd
Reviewed-on: https://go-review.googlesource.com/2270
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Now that we've removed all the C code in runtime and the C compilers,
there is no need to have a separate stackguard field to check for C
code on Go stack.
Remove field g.stackguard1 and rename g.stackguard0 to g.stackguard.
Adjust liblink and cmd/ld as necessary.
Change-Id: I54e75db5a93d783e86af5ff1a6cd497d669d8d33
Reviewed-on: https://go-review.googlesource.com/2144
Reviewed-by: Keith Randall <khr@golang.org>
Disabled by default, but invaluable when you need it.
Change-Id: If4a75d11d14f70b6840d339aaec4b940dc406493
Reviewed-on: https://go-review.googlesource.com/2012
Reviewed-by: Russ Cox <rsc@golang.org>
This was a copy-paste error from 9l. Besides incorrectly referring to
cnames9, 6l doesn't even use a->class, so simply remove this.
Fixes#9320
Change-Id: I0e3440c9dae1c3408eb795b3645f9f1dd8f50aed
Reviewed-on: https://go-review.googlesource.com/1516
Reviewed-by: Russ Cox <rsc@golang.org>
Previously, liblink would silently truncate register offset constants
to 32 bits. For example,
MOVD $0x200000004(R2),R3
would assemble to
addis r31,r2,0
addi r3,r31,4
To fix this, limit C_LACON to 32 bit (signed) offsets and introduce a
new C_DACON operand type for larger register offsets. We don't
implement this currently, but at least liblink will now give an error
if it encounters an address like this.
Change-Id: I8e87def8cc4cc5b75498b0fb543ac7666cf2964e
Reviewed-on: https://go-review.googlesource.com/1758
Reviewed-by: Minux Ma <minux@golang.org>
On ppc64, liblink rewrites MOVD's of >32-bit constants by putting the
constant in memory and rewriting the MOVD to load from that memory
address. However, there were two bugs in the condition:
a) owing to an incorrect sign extension, it triggered for all negative
constants, and
b) it could trigger for constant offsets from registers (addresses of
the form $n(Rm) in assembly)
Together, these meant instructions of the form MOVD $-n(Rm), x were
compiled by putting -n in memory and rewriting the MOVD to load this
constant from memory (completely dropping Rm).
Change-Id: I1f6cc980efa3e3d6f164b46c985b2c3b55971cca
Reviewed-on: https://go-review.googlesource.com/1752
Reviewed-by: Minux Ma <minux@golang.org>
When liblink sees something like
JMP x
...
x: JMP y
it rewrites the first jump to jump directly to y. This is
fine if y is a resolved label. However, it *also* does this
if y is a function symbol, but fails to carry over the
relocation that would later patch in that symbol's value. As
a result, the original jump becomes either a self-jump (if
relative) or a jump to PC 0 (if absolute).
Fix this by disabling this optimization if the jump being
patched in is a jump to a symbol.
LGTM=minux
R=rsc, minux
CC=golang-codereviews
https://golang.org/cl/185890044
Russ Cox
Shenghou Ma
David du Colombier
Austin Clements
Josh Bleecher Snyder
Keith Randall