2021630 - [riscv64] Hide disassembler and debug output behind JS_DISASM_RISCV64

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, task)

Description

[Rong Bao [:csmantle]]

JS_DISASM_ARM and JS_DISASM_ARM64 removes the disassembler for ARM and ARM64 when it's not needed (e.g. in a release build) [^1]. We should also do the same to RV64, as the facility is present but not used anywhere [^2].

Comment 1

[Rong Bao [:csmantle]]

Attachment: Bug 2021630 - [riscv64] Hide calls to disassembleInstr in non-Simulator code behind JS_DISASM_RISCV64. r=jandem

Comment 2

[Rong Bao [:csmantle]]

Attachment: Bug 2021630 - [riscv64] Part 2: (Drive-by) Rename functions to match existing convention. r=jandem

• Assembler::instr_at_put -> Assembler::putInstrAt
• Assembler::is_near -> Assembler::isNear

Comment 3

[Rong Bao [:csmantle]]

Attachment: Bug 2021630 - [riscv64] Part 3: (Drive-by) Remove definitely unused #include stmts. r=jandem

Comment 4

[Rong Bao [:csmantle]]

Comment on attachment 9550724 [details]
Bug 2021630 - [riscv64] Part 3: (Drive-by) Remove definitely unused #include stmts. r=jandem

This should go into a dedicated stack for RV64-specific cleanup.

Comment 5

[Rong Bao [:csmantle]]

Some ARES6 perf results:

After

Running... Air ( 1  to go)
firstIteration:     498.21 +- 3.80 ms
averageWorstCase:   186.61 +- 1.39 ms
steadyState:        82.35 +- 1.28 ms
summary:            331.78 +- 2.31 ms


Running... Basic ( 1  to go)
firstIteration:     260.83 +- 7.24 ms
averageWorstCase:   138.39 +- 3.39 ms
steadyState:        122.80 +- 4.53 ms
summary:            331.78 +- 2.31 ms


Running... Babylon ( 1  to go)
firstIteration:     480.13 +- 14.84 ms
averageWorstCase:   205.47 +- 14.40 ms
steadyState:        146.61 +- 1.00 ms
summary:            331.78 +- 2.31 ms


Running... ML ( 1  to go)
firstIteration:     1645.06 +- 33.76 ms
averageWorstCase:   1477.98 +- 37.87 ms
steadyState:        1466.82 +- 33.10 ms
summary:            331.22 +- 2.26 ms
Success! Benchmark is now finished.

Before

Running... Air ( 1  to go)
firstIteration:     505.21 +- 10.86 ms
averageWorstCase:   187.75 +- 1.33 ms
steadyState:        81.61 +- 0.69 ms
summary:            333.05 +- 3.96 ms


Running... Basic ( 1  to go)
firstIteration:     261.87 +- 13.61 ms
averageWorstCase:   136.59 +- 5.82 ms
steadyState:        117.97 +- 4.42 ms
summary:            333.05 +- 3.96 ms


Running... Babylon ( 1  to go)
firstIteration:     500.13 +- 17.90 ms
averageWorstCase:   204.70 +- 8.58 ms
steadyState:        148.39 +- 2.45 ms
summary:            333.05 +- 3.96 ms


Running... ML ( 1  to go)
firstIteration:     1675.23 +- 35.80 ms
averageWorstCase:   1509.35 +- 36.54 ms
steadyState:        1490.10 +- 34.28 ms
summary:            333.05 +- 2.99 ms
Success! Benchmark is now finished.

Env

Platform: SpacemiT M1

Base commit:

commit 46fa95cd7f10222996ec267947ab94c5107b1475
Merge: 12d718e2a70 f027136b53e
Author: Lando <[e-mail]>
Date:   Thu Mar 5 21:48:37 2026 +0000

    Merge autoland to mozilla-central

Related mozconfig flags:

ac_add_options --disable-debug
ac_add_options --enable-debug-symbols
ac_add_options --enable-optimize
ac_add_options --disable-jitdump
ac_add_options --disable-jitspew

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/e1a76609dda9
https://hg.mozilla.org/integration/autoland/rev/3c1947c997b9
[riscv64] Hide calls to disassembleInstr in non-Simulator code behind JS_DISASM_RISCV64. r=jandem

Comment 7

[Serban Stanca [:SerbanS]]

https://hg.mozilla.org/mozilla-central/rev/3c1947c997b9

Comment 8

[Serban Stanca [:SerbanS]]

https://hg.mozilla.org/mozilla-central/rev/3c1947c997b9