x/arch's Plan 9 renderer decodes thirty-odd scalar loong64 operations
perfectly but prints them as "Unknown OP args", and names the
sign-extension pair EXT.W.B/EXT.W.H "?". The supplementary naming
pass re-renders them with the toolchain's own spellings: the families
whose operand order x/arch already prints the Plan 9 way trade only
the mnemonic, and the pointer loads and stores, the acquire loads,
the release stores, PRELD and ALSL are rebuilt from the decoded
arguments with the toolchain's operand order and its raw displacement
reading. ADDU16I.D, a macro helper the assembler never takes as
input, keeps the decoder's Unknown render.
The loong64 parity fixture grows from 73 to 385 rows, pinning every
unique four-byte corpus word the decoder accepts, and the LL/SC
displacement divergence in the encoder is documented for asm.
Assisted-by: GLM 5.3
arm64asm rejects three exception-space words the toolchain's corpus
assembles: the hypervisor call HVC, the secure monitor call SMC and
the speculation barrier SB. The supplementary naming table reads
the raw word in the error branch and renders the corpus spellings;
the corpus rows are pinned in the parity fixture and the boundary
test holds the unallocated neighbours on the placeholder.
Assisted-by: GLM 5.3
The names naming_amd64.go and naming_amd64_test.go carried the _amd64
filename suffix, which the go tool reads as an implicit GOARCH=amd64
build constraint: the tables disappeared from every non-amd64 build
and the package failed to compile for arm64, riscv64 and loong64, the
other three architectures the tool assembles. Renaming to
amd64_naming.go removes the constraint; the module builds again for
all four GOARCH values.
Assisted-by: GLM 5.3
The toolchain's assembler corpus carries 195 amd64 encodings the
x/arch decoder rejects or degenerates: the BMI1/BMI2 VEX families
(ANDN, BEXTR, BLSI, BLSMSK, BLSR, BZHI, MULX, PDEP, PEXT, RORX,
SARX, SHLX, SHRX), the 0F 01 quartet CLAC, STAC, RDPKRU and WRPKRU,
the bare and REX-only RDSEED forms, and UD1. The supplementary
naming table decodes the VEX prefix and the ModR/M shape and renders
the toolchain's own spellings; every corpus row is pinned in the
unlisted fixture and round-trips byte for byte through the encoder,
and the boundary test pins the prefix shapes no family carries.
Assisted-by: GLM 5.3
The operand-width reconciliation closes the byte-register fixture lines
byte for byte: XADDL, XCHGL, CMPXCHGL and CRC32 with byte registers, the
ALU and TEST immediates against AL and DL, and the unlisted accumulator
short forms. MOVL $0x7, DL stays mapped for the legal-encoding choice
alone: the toolchain's own table says "c6c207 or b207", go tool asm emits
b207, and the fixed-point invariant holds with it.
Assisted-by: GLM 5.3
Table-driven rows for the renderer's spellings (the L suffix or none with
a byte register encodes the byte form, every register joining at its low
byte), the refusals (W, Q and the MOVD alias take no byte register) and a
differential kernel of the B-suffixed spellings assembled through both
gasm and go tool asm, byte for byte.
Assisted-by: GLM 5.3
The suffixed scalar families derived the operand width from the mnemonic
alone, so a byte-spelled register under the L spelling or no suffix at all
encoded the widened form: XADDL DL, DL emitted 0F C1 where the byte form is
0F C0, CMPL AL, $7 emitted the 32-bit immediate form where the AL form is
3C 07, and CRC32 DL, R11 widened past the F0 byte opcode. operandWidth now
reconciles the suffix with the operands: a byte register (AL, DL, R8B, ...)
forces the 8-bit form, which is the text the toolchain's own disassembly
prints for those encodings, while the W and Q spellings never ride a byte
register and are refused as go tool asm refuses them (MOVQ AL, AX). The
shift count and the two- and three-operand IMUL forms stay out of the
reconciliation, and the byte accumulator short forms now belong to the AL
spelling alone, matching the toolchain's division (ADDB $3, AX is
80 c0 03, TESTB $7, AX is f6 c0 07).
Assisted-by: GLM 5.3
The launch-failure audit raced the clock: it asserted the dead debuggee
surfaced within 1.5 seconds, a bound the loaded machine behind a ten-way
test storm regularly starved past even though the poll detects the dead
notice within milliseconds of its appearance. The audit now proves the
property itself: a stub debuggee that starts in single-digit milliseconds
marks itself dead, so the notice is always inside the poll's budget and
the error must come from the dead-file watch, while the real binary is
checked without any wall-clock bound. A companion audit drives Kill
through a parked, a doubly killed and a run-to-exit session, the states
whose cleanup used to hang the package, under a watchdog.
Assisted-by: GLM 5.3
The Go runtime can migrate the debuggee's target-mode goroutine off the
process leader before PTRACE_TRACEME, which left the trace relation on a
thread the session never addressed: its stops starved the waits on the
leader, and a kill sequence that resumed nothing and then blocked in
Wait4 hung the whole package. The debuggee now reports the traced thread
in the launch handshake and parks with a thread-directed stop, every
ptrace request and wait addresses that thread, a SIGURG arriving on a
single-step resumes it as a single-step again instead of letting the
tracee run uncontrolled, a resume rejected with ESRCH lifts a group-stop
with SIGCONT and retries once, and Kill resumes, kills and reaps through
non-blocking waits so it returns for a tracee in any state.
Assisted-by: GLM 5.3
The CASALH entry carried the CASB/CASH opcode pattern where the acquire
forms take the full fixed field, so the word differed from the
toolchain's in one opcode bit. Pinned against the oracle word.
Assisted-by: GLM 5.3 Flash
Offsets beyond the split bands ride a per-function literal pool the way
the toolchain lays one out: a PC-relative literal load into REGTMP, then
the register-offset access (the pair family adds the base addition), the
pooled words appended after the last instruction behind the UNDEF guard,
deduplicated by value with the sign- and width-aware load selection.
The same differential pass against the corpus exposed three wrong-code
bugs and fixes them: the logical-immediate period marker rode the wrong
position for every element below 64 bits, so the 32-bit forms encoded a
different constant than written; the plain register operand of an
ADD/SUB against SP took the shifted-register form where the toolchain
uses the extended one with the identity extend, silently truncating
through UXTB; and the AUTIA1716 and AUTIB1716 hint constants were the
PACIA and PACIB encodings. An offset sweep across every band boundary
now pins all three against the live oracle.
Assisted-by: GLM 5.3 Flash
Offsets the single-instruction forms cannot carry lower the way the
toolchain lowers them: ADD or SUB moves the whole distance into REGTMP
within the ±4095 band, and the 24-bit band above it splits into an ADD of
the high half and an access of the low half, with the pair family taking
the two-ADD sequence. The split band follows loadStoreClass per width,
byte accesses taking the full 24 bits and the Q width the widest, so an
offset the toolchain pools is never split instead.
Assisted-by: GLM 5.3 Flash
The pair encoder derived the imm7 divisor from the width suffix alone, so
the 128-bit FP pairs divided their offsets by eight and encoded twice the
distance. The Q spellings scale by sixteen like every other 128-bit
access; the differential kernel carries them now.
Assisted-by: GLM 5.3 Flash
FMOVQ routes through the MOV load/store machinery in the plain, post-index,
pre-index and static-symbol forms. The Q width carries its size in the opc
field, so the store spelling is opc=10 and the access scales by sixteen;
both come from helpers now instead of the size exponent. The static-symbol
form takes the toolchain's twelve-byte ADRP + ADD + access fallback with the
R_ADDRARM64 pair. The register-to-register and immediate forms stay
rejected, matching the toolchain's own table.
Assisted-by: GLM 5.3 Flash
The hint NOP opcode 0F 1C /r with a memory operand is CLDEMOTE, a
memory-only instruction the toolchain's own table carries; the decoder
rejects the encoding instead of naming it. The rejected-encoding side
of the supplementary table names it from the bytes, and the corpus row
0f1c03 pins the text in the unlisted fixture, round trip byte exact.
Assisted-by: GLM 5.3 Flash
x/arch reports the ADCX, ADOX, RDSEED, RDPID, TPAUSE, UMONITOR, UMWAIT
and ENDBR families with no error but the degenerate zero instruction,
which GoSyntax renders as Op(0) under its prefix decoration and with a
length of one. A supplementary naming table keyed by the opcode
pattern restores the toolchain's own spellings and lengths; the parity
fixtures pin all 41 corpus rows (ENDBR32 alone, which the toolchain
cannot spell, pins as bytes and text in the focused naming test).
Assisted-by: GLM 5.3 Flash
The two bank-crossing quadword moves take the mandatory prefix by
direction: the toolchain renders F3 0F D6 as MOVQ2DQ with the MMX
source and F2 0F D6 as MOVDQ2Q with the XMM source, and the encoder
emitted F2 for both, so MOVQ2DQ encoded MOVDQ2Q.
Assisted-by: GLM 5.3 Flash
The toolchain writes the source immediate straight into imm[31:12]
(riscv64.s: AUIPC 24287, X10 encodes 7ffff517), and rejects values
beyond the signed 20-bit span; the encoder divided by 4096 instead and
truncated silently, so the high bits of every large AUIPC and LUI were
lost.
Assisted-by: GLM 5.3 Flash
The toolchain's disassembler prints the segment-prefixed disp32
absolute as FS:0, but the bare-name branch read the segment register
alone and dropped the offset, so MOVQ FS:0, DX silently encoded a
register move. The colon-offset form now lowers to the same
segment-absolute operand the 0(FS) spelling takes.
Assisted-by: GLM 5.3 Flash
The renderer spells a conditional move CMOV plus the condition alone
(CMOVLE, CMOVG), the width carried by the operand registers, so
CMOVLE parsed as the size L and the condition E and encoded CMOVE.
A suffix that is itself a condition name now reads as that condition
with the width from the destination register, and the Plan 9
size-prefixed spellings keep their parse.
Assisted-by: GLM 5.3 Flash
petrbalvin