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150 commits

Author SHA1 Message Date
Alan Donovan
f1fed742eb cmd: fix three printf problems reported by newest vet
Change-Id: Id70985d217c940eb022dbc95bfaa20373672512c
Reviewed-on: https://go-review.googlesource.com/c/go/+/712220
Auto-Submit: Alan Donovan <adonovan@google.com>
TryBot-Bypass: Alan Donovan <adonovan@google.com>
Commit-Queue: Alan Donovan <adonovan@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2025-10-15 13:54:06 -07:00
Alan Donovan
d4830c6130 cmd/internal/obj: fix Link.Diag printf errors
go1.26's vet printf checker can associate the printf-wrapper
property with local vars and struct fields if they are assigned
from a printf-like func literal (CL 706635). This leads to better
detection of mistakes.

Change-Id: I604be1e200aa1aba75e09d4f36ab68c1dba3b8a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/710195
Auto-Submit: Alan Donovan <adonovan@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2025-10-08 13:44:19 -07:00
wangboyao
371c1d2fcb cmd/internal/obj/riscv: add support for vector unit-stride fault-only-first load instructions
Add support for vector unit-stride fault-only-first load instructions to the RISC-V
assembler. This includes vle8ff, vle16ff, vle32ff and vle64ff.

Change-Id: I5575a1ea155663852f92194fb79f08b5d52203de
Reviewed-on: https://go-review.googlesource.com/c/go/+/690115
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-09-24 06:21:53 -07:00
lxq015
ef05b66d61 cmd/internal/obj/riscv: add support for Zicond instructions
This patch implement assembler for the Zicond extension: CZEROEQZ and CZERONEZ.

Follow-up to CL 631576
Updates #75350

Change-Id: Icf4be131fe61c3b7a3bde4811cf42dc807660907
GitHub-Last-Rev: 6539cc86cb
GitHub-Pull-Request: golang/go#75408
Reviewed-on: https://go-review.googlesource.com/c/go/+/702677
Reviewed-by: Mark Freeman <markfreeman@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
TryBot-Bypass: Joel Sing <joel@sing.id.au>
2025-09-17 18:54:30 -07:00
Joel Sing
e2cfc1eb3a cmd/internal/obj/riscv: improve handling of float point moves
Translate moves from an integer register to a floating point register, or
from a floating point register to an integer register, to the appropriate
move instruction (i.e. FMVXW/FMVWX/FMVXD/FMVDX).

Add support for MOVF with a constant - we previously added support for MOVD
but not for MOVF. Add special handling for 0.0, which we can translate to
a move from the zero register to a floating point register (leveraging the
above mentioned change).

Change-Id: If8df2f5610e69b4ec0af85efb884951024685f5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/703216
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Mark Freeman <markfreeman@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
2025-09-16 08:43:10 -07:00
wangboyao
6b8d507508 cmd/internal/obj/riscv: implement vector segment load/store instructions
https://github.com/riscv/riscv-opcodes/pull/361. After this pr was
merged, riscv-opcode can generate RVV segment load/store instructions
for Go. Implement vector segment load/store instuctions.

Change-Id: I154bb75be70c0a45e2279a75c67f68b5bb57c36e
Reviewed-on: https://go-review.googlesource.com/c/go/+/691695
Reviewed-by: Mark Freeman <markfreeman@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-09-15 18:57:04 -07:00
Mark Ryan
dd8276657f cmd/asm, cmd/internal/obj: add riscv64 generic CSR ops
Support is added for the generic RISC-V CSR operations; CSRRC, CSRRCI,
CSRRS, CSRRSI, CSRRW, CSRRWI.  These instructions require special
handling as their second operand is a symbolic CSR register name and
not an immediate value or a register.  CSR names are implemented as
special operands.

RISC-V CSRs are not currently saved and restored when a go routine is
asynchronously pre-empted so it is only safe to use these instructions
in hand written assembler.  Note that CSRRS was already partially
supported by the assembler so this restriction predates this commit.
We mention it here as this commit makes CSRRS much easier to use.

Change-Id: I9ff8d804328b418a879d463e7d9cc31f489c7a00
Reviewed-on: https://go-review.googlesource.com/c/go/+/630519
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
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Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
2025-09-12 01:12:45 -07:00
Meng Zhuo
b9a4a09b0f runtime: remove duff support for riscv64
Change-Id: I987d9f49fbd2650eef4224f72271bf752c54d39c
Reviewed-on: https://go-review.googlesource.com/c/go/+/700538
Reviewed-by: Mark Freeman <markfreeman@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
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Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
2025-09-09 19:42:25 -07:00
qiulaidongfeng
4ee0df8c46 cmd: remove dead code
Fixes #74076

Change-Id: Icc67b3d4e342f329584433bd1250c56ae8f5a73d
Reviewed-on: https://go-review.googlesource.com/c/go/+/690635
Reviewed-by: Alan Donovan <adonovan@google.com>
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2025-08-05 10:31:25 -07:00
Keith Randall
6f6c6c5782 cmd/internal/obj: rip out argp adjustment for wrapper frames
The previous CL made this adjustment unnecessary. The argp field
is no longer used by the runtime.

Change-Id: I3491eeef4103c6653ec345d604c0acd290af9e8f
Reviewed-on: https://go-review.googlesource.com/c/go/+/685356
Reviewed-by: Michael Knyszek <mknyszek@google.com>
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Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2025-07-24 16:24:50 -07:00
Mark Ryan
0d7dc6842b cmd/internal/obj/riscv: fix vector integer multiply add
The RISC-V integer vector multiply add instructions are not encoded
correctly; the first and second arguments are swapped. For example,
the instruction

VMACCVV V1, V2, V3

encodes to

b620a1d7 or vmacc.vv v3,v1,v2

and not

b61121d7 or vmacc.vv v3,v2,v1

as expected.

This is inconsistent with the argument ordering we use for 3
argument vector instructions, in which the argument order, as given
in the RISC-V specifications, is reversed, and also with the vector
FMA instructions which have the same argument ordering as the vector
integer multiply add instructions in the "The RISC-V Instruction Set
Manual Volume I". For example, in the ISA manual we have the
following instruction definitions

; Integer multiply-add, overwrite addend
vmacc.vv vd, vs1, vs2, vm    # vd[i] = +(vs1[i] * vs2[i]) + vd[i]

; FP multiply-accumulate, overwrites addend
vfmacc.vv vd, vs1, vs2, vm    # vd[i] = +(vs1[i] * vs2[i]) + vd[i]

It's reasonable to expect that the Go assembler would use the same
argument ordering for both of these instructions. It currently does
not.

We fix the issue by switching the argument ordering for the vector
integer multiply add instructions to match those of the vector FMA
instructions.

Change-Id: Ib98e9999617f991969e5c831734b3bb3324439f6
Reviewed-on: https://go-review.googlesource.com/c/go/+/670335
Reviewed-by: Carlos Amedee <carlos@golang.org>
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2025-05-21 07:19:19 -07:00
Mark Ryan
d000963d04 cmd/internal/obj/riscv: reject invalid vadc/vsbc encodings
The RISC-V Instruction Set Manual Volume states that "for vadc and
vsbc, the instruction encoding is reserved if the destination vector
register is v0". The assembler currently allows instructions like

VADCVVM	V1, V2, V0, V0

to be assembled. It's not clear what the behaviour of such
instructions will be on target hardware so it's best to disallow
them.

For reference, binutils (2.44-3.fc42) allows the instruction

vadc.vvm v0, v4, v8, v0

to be assembled and the instruction actually executes on a Banana PI
F3 without crashing. However, clang (20.1.2) refuses to assemble the
instruction, producing the following error.

error: the destination vector register group cannot be V0
        vadc.vvm v0, v4, v8, v0
                 ^
Change-Id: Ia913cbd864ae8dbcf9227f69b963c93a99481cff
Reviewed-on: https://go-review.googlesource.com/c/go/+/669315
Reviewed-by: Carlos Amedee <carlos@golang.org>
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2025-05-08 01:53:43 -07:00
Keith Randall
fa2bb342d7 Revert "cmd/compile: allow all of the preamble to be preemptible"
This reverts commits

3f3782feed (CL 648518)
b386b62852 (CL 668475)

Fixes #73542

Change-Id: I218851c5c0b62700281feb0b3f82b6b9b97b910d
Reviewed-on: https://go-review.googlesource.com/c/go/+/670055
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
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2025-05-05 13:08:27 -07:00
Joel Sing
1cc624fd62 cmd/internal/obj/riscv: add support for vector permutation instructions
Add support for vector permutation instructions to the RISC-V assembler.
This includes integer scalar move, floating point scalar move, slide up
and slide down, register gather, compression and whole vector register
move instructions.

Change-Id: I1da9f393091504fd81714006355725b8b9ecadea
Reviewed-on: https://go-review.googlesource.com/c/go/+/646780
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Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
2025-05-02 04:24:52 -07:00
Joel Sing
936ecc3e24 cmd/internal/obj/riscv: add support for vector mask instructions
Add support for vector mask instructions to the RISC-V assembler.
These allow manipulation of vector masks and include mask register
logical instructions, population count and find-first bit set
instructions.

Change-Id: I3ab3aa0f918338aee9b37ac5a2b2fdc407875072
Reviewed-on: https://go-review.googlesource.com/c/go/+/646779
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
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Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
2025-05-02 04:24:40 -07:00
Joel Sing
2e60916f6e cmd/internal/obj/riscv: add support for vector reduction instructions
Add support for vector reduction instructions to the RISC-V assembler,
including single-width integer reduction, widening integer reduction,
single-width floating-point reduction and widening floating-point
reduction.

Change-Id: I8f17bef11389f3a017e0430275023fc5d75936e3
Reviewed-on: https://go-review.googlesource.com/c/go/+/646778
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
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Reviewed-by: Carlos Amedee <carlos@golang.org>
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2025-05-02 04:24:27 -07:00
Joel Sing
5a342266e6 cmd/internal/obj/riscv: add support for vector floating-point instructions
Add support for vector floating-point instructions to the RISC-V
assembler. This includes single-width and widening addition and
subtraction, multiplication and division, fused multiply-addition,
comparison, min/max, sign-injection, classification and type
conversion instructions.

Change-Id: I8bceb1c5d7eead0561ba5407ace00805a6144f51
Reviewed-on: https://go-review.googlesource.com/c/go/+/646777
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
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Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
2025-05-01 05:55:31 -07:00
Keith Randall
3f3782feed cmd/compile: allow all of the preamble to be preemptible
We currently make some parts of the preamble unpreemptible because
it confuses morestack. See comments in the code.

Instead, have morestack handle those weird cases so we can
remove unpreemptible marks from most places.

This CL makes user functions preemptible everywhere if they have no
write barriers (at least, on x86). In cmd/go the fraction of functions
that need preemptible markings drops from 82% to 36%. Makes the cmd/go
binary 0.3% smaller.

Update #35470

Change-Id: Ic83d5eabfd0f6d239a92e65684bcce7e67ff30bb
Reviewed-on: https://go-review.googlesource.com/c/go/+/648518
Auto-Submit: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2025-04-25 12:21:48 -07:00
Joel Sing
4c1b8ca98c cmd/internal/obj/riscv: add support for vector fixed-point arithmetic instructions
Add support for vector fixed-point arithmetic instructions to the
RISC-V assembler. This includes single width saturating addition
and subtraction, averaging addition and subtraction and scaling
shift instructions.

Change-Id: I9aa27e9565ad016ba5bb2b479e1ba70db24e4ff5
Reviewed-on: https://go-review.googlesource.com/c/go/+/646776
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-04-01 05:31:22 -07:00
Joel Sing
535e0daefd cmd/internal/obj/riscv: add support for vector integer arithmetic instructions
Add support for vector integer arithmetic instructions to the RISC-V
assembler. This includes vector addition, subtraction, integer
extension, add-with-carry, subtract-with-borrow, bitwise logical
operations, comparison, min/max, integer division and multiplication
instructions.

Change-Id: I8c191ef8e31291e13743732903e4f12356133a46
Reviewed-on: https://go-review.googlesource.com/c/go/+/646775
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
2025-03-29 05:54:51 -07:00
Joel Sing
d88f93f720 cmd/internal/obj/riscv,internal/bytealg: synthesize MIN/MAX/MINU/MAXU instructions
Provide a synthesized version of the MIN/MAX/MINU/MAXU instructions
if they're not natively available. This allows these instructions to
be used in assembly unconditionally.

Use MIN in internal/bytealg.compare.

Cq-Include-Trybots: luci.golang.try:gotip-linux-riscv64
Change-Id: I8a5a3a59f0a9205e136fc3d673b23eaf3ca469f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/653295
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
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2025-03-27 05:52:28 -07:00
Joel Sing
d37624881f cmd/internal/obj/riscv: improve constant construction
Attempt to construct large constants that have a consecutive sequence
of ones from a small negative constant, with a logical right and/or
left shift. This allows for a large range of mask like constants to be
constructed with only two or three instructions, avoiding the need to
load from memory.

Change-Id: I35a77fecdd2df0ed3f33b772d518f85119d4ff66
Reviewed-on: https://go-review.googlesource.com/c/go/+/652778
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Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
2025-03-27 04:26:47 -07:00
Joel Sing
af133d86e4 cmd/internal/obj/riscv: factor out shift constant code
Move the code that tests to see if a constant can be represented by a
32 bit signed integer and a logical left shift. This reduces duplication
and increases readability. Also add test coverage now that this is an
independent function.

Change-Id: Id25395b1380b00cf5b69ca201b7715ef84f7ade6
Reviewed-on: https://go-review.googlesource.com/c/go/+/652777
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2025-03-21 17:40:34 -07:00
Mark Ryan
c386ed107e cmd/internal/obj/riscv: fix the encoding for REV8 and ORCB
The instructions are currently encoded and validated using an
iIIEncoding which is incorrect as these instructions do not
take an immediate operand.  Encode them instead using an
rIIEncoding as is done for the other two register argument bitmanip
instructions.

Change-Id: Ia4d9c6f6ebd2dfc381935ebc11afa8fc3664232b
Reviewed-on: https://go-review.googlesource.com/c/go/+/637317
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
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2025-03-20 21:24:28 -07:00
Mark Ryan
1aee4f3464 cmd/internal/obj/riscv: prevent panics on bad branches
Syntactically incorrect branches, such as

BEQ	X5, X6, $1
BEQ	X5, X6, 31(X10)

cause the assembler to panic, which they shouldn't really do.  It's
better for the user to see a normal error, as reported for other
syntax errors in riscv64 assembly.  The panics also prevent us
from writing negative tests for these sorts of errors.

Here we fix the issue by ensuring we generate a normal error instead
of panicking when the user provides an invalid branch target.  We
also add a couple of negative tests.

Change-Id: I1da568999a75097484b61a01d418f5d4be3e04fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/637316
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
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Reviewed-by: David Chase <drchase@google.com>
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2025-03-19 07:00:36 -07:00
Mark Ryan
24b395119b cmd/internal/obj/riscv: prevent duplicate error reports
The riscv64 Go assembler can output certain errors, ones produced by
instructionsForProg, multiple times.  These errors are guaranteed to
be output at least twice and can appear three or more times if a
rescan is needed to recompute branch addresses.  For example, the
syntactically incorrect instruction

MOV	(X10), $1

will generate at least two identical errors

asm: 86076 (asm.s:21524)	MOV	(X10), $1: unsupported MOV
asm: 86076 (asm.s:21524)	MOV	(X10), $1: unsupported MOV
asm: assembly failed

In addition to confusing the user, these duplicate errors make it
difficult to write negative tests for certain types of instructions,
e.g., branches, whose duplicate errors are not always identical,
and so not ignored by endtoend_test.go.

We fix the issue by returning from preprocess if any errors have been
generated by the time we reach the end of the rescan loop. One
implication of this change is that validation errors will no longer
be reported if an error is generated earlier in the preprocess stage.
Negative test cases for validation errors are therefore moved to
their own file as the existing riscv64error.s file contains errors
generated by instructionsForProg that will now suppress the
validation errors.

Change-Id: Iffacdbefce28f44970dd5dda44990b822b8a23d4
Reviewed-on: https://go-review.googlesource.com/c/go/+/637315
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2025-03-18 18:36:01 -07:00
Joel Sing
37e9c5eaba cmd/internal/obj/riscv: implement vector load/store instructions
Implement vector unit stride, vector strided, vector indexed and
vector whole register load and store instructions.

The vector unit stride instructions take an optional vector mask
register, which if specified must be register V0. If only two
operands are given, the instruction is encoded as unmasked.

The vector strided and vector indexed instructions also take an
optional vector mask register, which if specified must be register
V0. If only three operands are given, the instruction is encoded as
unmasked.

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Change-Id: I35e43bb8f1cf6ae8826fbeec384b95ac945da50f
Reviewed-on: https://go-review.googlesource.com/c/go/+/631937
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Pengcheng Wang <wangpengcheng.pp@bytedance.com>
2025-02-27 03:47:20 -08:00
Meng Zhuo
cdc9560794 all: implement plugin build mode for riscv64
Change-Id: I8d7bbeebbf4a46f2fd8d630b1edbaf79b8ffccc5
Reviewed-on: https://go-review.googlesource.com/c/go/+/420114
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
TryBot-Bypass: Joel Sing <joel@sing.id.au>
2025-02-19 17:54:34 -08:00
Joel Sing
d7c242a19a cmd/internal/obj/riscv: support MOVD with floating point constants
Currently, we only support loading of values from memory (or other
registers). Add floating point constant support to MOVD. This is
implemented by storing the floating point constant to a symbol,
which is then loaded into the floating point register.

Change-Id: I6db242d27f606f0d5d084a3ab93538698d3a4f8c
Reviewed-on: https://go-review.googlesource.com/c/go/+/631876
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-02-14 19:41:30 -08:00
Joel Sing
c8545439b5 cmd/asm,cmd/internal/obj/riscv: implement vector configuration setting instructions
Implement vector configuration setting instructions (VSETVLI,
VSETIVLI, VSETL).  These allow the vector length (vl) and vector
type (vtype) CSRs to be configured via a single instruction.
Unfortunately each instruction has its own dedicated encoding.

In the case of VSETVLI/VSETIVLI, the vector type is specified via
a series of special operands, which specify the selected element
width (E8, E16, E32, E64), the vector register group multiplier
(M1, M2, M4, M8, MF2, MF4, MF8), the vector tail policy (TU, TA)
and vector mask policy (MU, MA). Note that the order of these
special operands matches non-Go assemblers.

Partially based on work by Pengcheng Wang <wangpengcheng.pp@bytedance.com>.

Cq-Include-Trybots: luci.golang.try:gotip-linux-riscv64
Change-Id: I431f59c1e048a3e84754f0643a963da473a741fe
Reviewed-on: https://go-review.googlesource.com/c/go/+/631936
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2025-02-14 07:13:11 -08:00
Meng Zhuo
371ee1469c cmd/link,cmd/internal: add R_GOT_PCREL_ITYPE_RELOC for riscv64
This CL adds new relocation type for riscv64: R_GOT_PCREL_ITYPE_RELOC
which generate an AUIPC + I-type pair with relocation type of GOT_HI20
and PCREL_LO12_I.
According to RISCV elf psabi doc, medium position independent code
model, the GNU as example is:

```
		# Calculate address of non-local symbol
.Ltmp3: aupipc	a0, %got_pcrel_hi(symbol)
	ld	a0, %pcrel_lo(.Ltmp3)(a0)
```

Change-Id: I719dd05e009ca2d9291f0689b346c059f9c56918
Reviewed-on: https://go-review.googlesource.com/c/go/+/612635
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-02-13 19:04:13 -08:00
Joel Sing
7a2f757c52 cmd/internal/obj/riscv: update references to RISC-V specification
Update references to version 20240411 of the RISC-V specifications.
Reorder and regroup instructions to maintain ordering. Also be
consistent with formatting.

The instruction encodings table was seemingly missed in CL 616115.

Change-Id: I47b7c8538383ff3b0503ba59db570c3d4f0d5653
Reviewed-on: https://go-review.googlesource.com/c/go/+/631935
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Pengcheng Wang <wangpengcheng.pp@bytedance.com>
2025-02-07 02:19:17 -08:00
Joel Sing
dc8ceb63a8 cmd/internal/obj/riscv: rework instruction encoding information
Currently, instruction encoding is a slice of encoding types, which
is indexed by a masked version of the riscv64 opcode. Additional
information about some instructions (for example, if an instruction
has a ternary form and if there is an immediate form for an instruction)
is manually specified in other parts of the assembler code.

Rework the instruction encoding information so that we use a table
driven form, providing additional data for each instruction where
relevant. This means that we can simplify other parts of the code
by simply looking up the instruction data and reusing minimal logic.

Change-Id: I7b3b6c61a4868647edf28bd7dbae2150e043ae00
Cq-Include-Trybots: luci.golang.try:gotip-linux-riscv64
Reviewed-on: https://go-review.googlesource.com/c/go/+/622535
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2024-11-21 22:31:25 +00:00
Russ Cox
5b20eec8a0 cmd/internal/obj: replace obj.Addrel func with LSym.AddRel method
The old API was to do

	r := obj.AddRel(sym)
	r.Type = this
	r.Off = that
	etc

The new API is:

	sym.AddRel(ctxt, obj.Reloc{Type: this: Off: that, etc})

This new API is more idiomatic and avoids ever having relocations
that are only partially constructed. Most importantly, it sets up
for sym.AddRel being able to check relocation validity in the future.
(Passing ctxt is for use in validity checking.)

Passes golang.org/x/tools/cmd/toolstash/buildall.

Change-Id: I042ea76e61bb3bf6402f98ca11291a13f4799972
Reviewed-on: https://go-review.googlesource.com/c/go/+/625616
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2024-11-07 12:17:10 +00:00
Joel Sing
89d7f03172 cmd/internal/obj/riscv: update RISC-V instruction table
Regenerate RISC-V instruction table from the riscv-opcodes repository,
due to various changes and shuffling upstream.

This has been changed to remove pseudo-instructions, since Go only
needs the instruction encodings and including the pseudo-instructions
is creating unnecessary complications (for example, the inclusion
of ANOP and ARET, as well as strangely named aliases such as
AJALPSEUDO/AJALRPSEUDO). Remove pseudo-instructions that are not
currently supported by the assembler and add specific handling for
RDCYCLE, RDTIME and RDINSTRET, which were previously implemented
via the instruction encodings.

Change-Id: I78be4506ba6b627eba1f321406081a63bab5b2e6
Cq-Include-Trybots: luci.golang.try:gotip-linux-riscv64
Reviewed-on: https://go-review.googlesource.com/c/go/+/616116
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2024-10-30 13:30:43 +00:00
Lin Runze
b45c7f1661 cmd/internal/obj: add prologue_end DWARF stmt for riscv64
This patch adds prologue_end statement to the DWARF info for riscv64,
which delve debugger uses for skip stacksplit prologue.

Change-Id: I4e5d9c26202385f65b3118b16f53f66de9d327f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/620295
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2024-10-25 13:46:59 +00:00
Joel Sing
4646556ba4 cmd/internal/obj,cmd/asm: add vector registers to riscv64 assembler
This adds V0 through V31 as vector registers, which are available on CPUs
that support the V extension.

Change-Id: Ibffee3f9a2cf1d062638715b3744431d72d451ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/595404
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: 鹏程汪 <wangpengcheng.pp@bytedance.com>
2024-10-24 12:32:56 +00:00
Mark Ryan
6a730e1ef0 cmd/internal/obj/riscv: rename the iIEncoding
We rename it to iIIEncoding to reflect the fact that instructions
that use this encoding take two integer registers.  This change
will allow us to add a new encoding for I-type instructions that
take a single integer register.  This new encoding will be used for
instructions that modify CSRs.

Change-Id: Ic507d0020e18f6aa72353f4d3ffcd0e868261e7a
Reviewed-on: https://go-review.googlesource.com/c/go/+/614355
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: David Chase <drchase@google.com>
2024-09-27 00:32:20 +00:00
Joel Sing
0ee5d20b1f cmd/compile,cmd/internal/obj/riscv: always provide ANDN, ORN and XNOR for riscv64
The ANDN, ORN and XNOR RISC-V Zbb extension instructions are easily
synthesised. Make them always available by adding support to the
riscv64 assembler so that we either emit two instruction sequences,
or a single instruction, when permitted by the GORISCV64 profile.
This means that these instructions can be used unconditionally,
simplifying compiler rewrite rules, codegen tests and manually
written assembly.

Around 180 instructions are removed from the Go binary on riscv64
when built with rva22u64.

Change-Id: Ib2d90f2593a306530dc0ed08a981acde4d01be20
Reviewed-on: https://go-review.googlesource.com/c/go/+/611895
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Tim King <taking@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2024-09-12 15:03:44 +00:00
Joel Sing
20f052c83c cmd/internal/obj/riscv: check immediate for rotation instructions
Ensure that the immediate for a RORI or RORIW instruction are within range,
adding test coverage. Also use a consistent "immediate out of range" error
for both rotations and shifts.

Change-Id: Id687d7c6e028786f607e9519bbb64dab62b6cf3d
Reviewed-on: https://go-review.googlesource.com/c/go/+/572735
Reviewed-by: M Zhuo <mengzhuo1203@gmail.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2024-04-07 03:32:27 +00:00
Joel Sing
3659b8756a cmd/internal/obj/riscv: use native rotation instructions for rva22u64
When rva22u64 is available, we can now use the native rotation instructions
from the Zbb extension. Use these instead of synthesising rotation
instructions.

This provides a significant performance gain for SHA-512, the following
benchmarked on a StarFive VisionFive 2:

                    │ sha512.rva20u64 │            sha512.rva22u64            │
                    │       B/s       │      B/s       vs base                │
Hash8Bytes/New-4         859.4Ki ± 0%   1337.9Ki ± 0%  +55.68% (p=0.000 n=10)
Hash8Bytes/Sum384-4      888.7Ki ± 1%   1308.6Ki ± 1%  +47.25% (p=0.000 n=10)
Hash8Bytes/Sum512-4      869.1Ki ± 0%   1269.5Ki ± 1%  +46.07% (p=0.000 n=10)
Hash1K/New-4             19.83Mi ± 0%    29.03Mi ± 0%  +46.38% (p=0.000 n=10)
Hash1K/Sum384-4          20.00Mi ± 0%    28.86Mi ± 0%  +44.30% (p=0.000 n=10)
Hash1K/Sum512-4          19.93Mi ± 0%    28.72Mi ± 0%  +44.11% (p=0.000 n=10)
Hash8K/New-4             23.85Mi ± 0%    34.12Mi ± 0%  +43.09% (p=0.000 n=10)
Hash8K/Sum384-4          23.88Mi ± 0%    34.09Mi ± 0%  +42.77% (p=0.000 n=10)
Hash8K/Sum512-4          23.87Mi ± 0%    34.07Mi ± 0%  +42.71% (p=0.000 n=10)
geomean                  7.399Mi         10.78Mi       +45.77%

Change-Id: I9dca8e3f311eea101684c806cb998872dc697288
Reviewed-on: https://go-review.googlesource.com/c/go/+/572716
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: M Zhuo <mengzhuo1203@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Auto-Submit: Emmanuel Odeke <emmanuel@orijtech.com>
2024-03-26 02:22:30 +00:00
Joel Sing
a6ecdf29e3 cmd/internal/obj/riscv: improve register MOVB/MOVH/MOVBU/MOVHU for rva22u64
When GORISCV64 enables rva22u64, use SEXTB for MOVB, SEXTH for MOVH, ZEXTH
for MOVHU and ADDUW for MOVWU. These are single instruction alternatives
to the two instruction shift sequences that are needed otherwise.

Change-Id: Iea5e394f57e238ae8771400a87287c1ee507d44c
Reviewed-on: https://go-review.googlesource.com/c/go/+/572736
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: M Zhuo <mengzhuo1203@gmail.com>
2024-03-22 04:42:21 +00:00
Wang Yaduo
db423dde85 cmd/internal/obj: support Zba, Zbb, Zbs extensions in riscv64 assembler
Add assembler support for Zba, Zbb, Zbs extensions, which are
mandatory in the rva22u64 profile. These can be used to accelerate
address computation and bit manipulation.

Change-Id: Ie90fe6b76b1382cf69984a0e71a72d3cba0e750a
Reviewed-on: https://go-review.googlesource.com/c/go/+/559655
Reviewed-by: M Zhuo <mengzhuo1203@gmail.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2024-03-20 14:19:33 +00:00
Joel Sing
997636760e cmd/compile,cmd/internal/obj: provide rotation pseudo-instructions for riscv64
Provide and use rotation pseudo-instructions for riscv64. The RISC-V bitmanip
extension adds support for hardware rotation instructions in the form of ROL,
ROLW, ROR, RORI, RORIW and RORW. These are easily implemented in the assembler
as pseudo-instructions for CPUs that do not support the bitmanip extension.

This approach provides a number of advantages, including reducing the rewrite
rules needed in the compiler, simplifying codegen tests and most importantly,
allowing these instructions to be used in assembly (for example, riscv64
optimised versions of SHA-256 and SHA-512). When bitmanip support is added,
these instruction sequences can simply be replaced with a single instruction
if permitted by the GORISCV64 profile.

Change-Id: Ia23402e1a82f211ac760690deb063386056ae1fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/565015
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: M Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
2024-03-07 14:57:07 +00:00
Meng Zhuo
3580c212c2 cmd/asm, cmd/internal/obj: enable rounding mode suffix for riscv64
This CL adds rounding modes for riscv64 floating point conversion
instructions by suffix with 5 modes: RNE, RTZ, RDN, RUP and RMM.

For example, for round to nearest (RNE), we can use `FCVTLD.RNE`
According to RISCV manual 8.7 and 9.5, we changed these
conversion instructions:

FCVTWS
FCVTLS
FCVTWUS
FCVTLUS
FCVTWD
FCVTLD
FCVTWUD
FCVTLUD

Note: Round towards zero (RTZ) by default for all these instructions above.

Change-Id: I491e522e14d721e24aa7f528ee0c4640c54c5808
Reviewed-on: https://go-review.googlesource.com/c/go/+/504736
Reviewed-by: Joel Sing <joel@sing.id.au>
Run-TryBot: M Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2024-02-21 14:34:57 +00:00
Meng Zhuo
9840d38cdb cmd/internal/obj/riscv: add support of PCALIGN directive
Add support for PCALIGN directive on riscv.
This directive can be used within Go asm to align instruction
by padding NOP directives.

This patch also adds a test to verify the correctness of the PCALIGN
directive.

Original credit by Cooper Qu (Alibaba)
https://gitee.com/xuantie_riscv/xuantie-patch

Change-Id: I8b6524a2bf81a1baf7c9d04b7da2db6c1a7b428f
Reviewed-on: https://go-review.googlesource.com/c/go/+/541740
Run-TryBot: M Zhuo <mzh@golangcn.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Wang Yaduo <wangyaduo@linux.alibaba.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2023-11-22 01:50:18 +00:00
Joel Sing
e816eb5014 cmd/internal/obj/riscv: improve handling of invalid assembly
Currently, instruction validation failure will result in a panic during
encoding. Furthermore, the errors generated do not include the PC or
file/line information that is normally present.

Fix this by:

- Tracking and printing the *obj.Prog associated with the instruction,
  including the assembly instruction/opcode if it differs. This provides
  the standard PC and file/line prefix, which is also expected by assembly
  error end-to-end tests.

- Not proceeding with assembly if errors exist - with the current design,
  errors are identified during validation, which is run via preprocess.
  Attempts to encode invalid instructions will intentionally panic.

Add some additional riscv64 encoding errors, now that we can actually do so.

Change-Id: I64a7b83680c4d12aebdc96c67f9df625b5ef90d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/523459
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: M Zhuo <mzh@golangcn.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: M Zhuo <mzh@golangcn.org>
2023-11-09 13:39:57 +00:00
Joel Sing
dc74a3dd4f cmd/internal/obj/riscv: support subtraction with a constant
Allow SUB and SUBW to be specified with a constant, which are mapped
to ADDI and ADDIW with negated values.

Change-Id: I7dc55692febc81ea87393b0a3a7d23a43c30313b
Reviewed-on: https://go-review.googlesource.com/c/go/+/538915
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: M Zhuo <mzh@golangcn.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Wang Yaduo <wangyaduo@linux.alibaba.com>
Reviewed-by: Mauri de Souza Meneguzzo <mauri870@gmail.com>
2023-11-07 10:37:24 +00:00
Wang Yaduo
d33548d178 cmd/internal/obj/riscv: fix the offset of JALR transformed from JAL
Currently, the offset of JALR is zero all the time, which is transformed
from JAL with over ±1MB offset. This causes the segment fault for the
wrong address.

Change-Id: I4dcb3eb13bd1ea71e9eb27f07c03ffec376608ab
Reviewed-on: https://go-review.googlesource.com/c/go/+/538135
Run-TryBot: M Zhuo <mzh@golangcn.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: M Zhuo <mzh@golangcn.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2023-11-07 01:22:04 +00:00
Joel Sing
bda5e6c3d0 cmd/internal/obj/riscv,cmd/link: rework riscv64 call relocations
The riscv64 assembler and linker generate three types of calls.
Most calls are made via a single JAL instruction, however this is
limited to +/-1MB of text. In the case where a call target is
unreachable (or unknown), the JAL targets an AUIPC+JALR trampoline.
All other cases use AUIPC+JALR pairs, including the case where a
single function exceeds 1MB in text size, potentially making it
impossible to reach trampolines.

Currently, the single instruction JAL call is marked with R_RISCV_CALL
and the two instruction AUIPC+JALR call is marked with
R_RISCV_PCREL_ITYPE, which is also used for memory load instructions.
This means that we have no way to identify that the latter is a call.

Switch to using R_RISCV_CALL to mark the AUIPC+JALR pair (aligning
somewhat with the elf.R_RISCV_CALL, which is deprecated in favour of
elf.R_RISCV_CALL_PLT). Add R_RISCV_JAL and use this to mark the single
instruction JAL direct calls. This is clearer and allows us to map
elf.R_RISCV_CALL_PLT to Go's R_RISCV_CALL.

Add all three types to IsDirectCall, so that direct calls are correctly
identified when a function exceeds 1MB of text.

Fixes #62465

Change-Id: Id3eea09688a2b7d6e481eae9ed0aa0d1f9a3a48f
Reviewed-on: https://go-review.googlesource.com/c/go/+/520095
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Than McIntosh <thanm@google.com>
2023-09-19 18:10:13 +00:00