Closed Bug 1574002 Opened 6 years ago Closed 6 years ago

Add method to programmatically view disassembly of Wasm exported function

Tracking

()

Status:

RESOLVED FIXED

Milestone:

mozilla70

Tracking Flags:

Tracking

Status

firefox70

---

fixed

People

(Reporter: rhunt, Assigned: rhunt)

Details

Attachments

(4 files)

Bug 1574002 - Add jit::Disassemble as a wrapper around existing in-tree disassemblers. r?lth 6 years ago Ryan Hunt [:rhunt] 47 bytes, text/x-phabricator-request		Details \| Review
Bug 1574002 - Build Zydis even when not using Cranelift. r?lth 6 years ago Ryan Hunt [:rhunt] 47 bytes, text/x-phabricator-request		Details \| Review
Bug 1574002 - Use jit::Disassemble for Cranelift JitSpew. r?lth 6 years ago Ryan Hunt [:rhunt] 47 bytes, text/x-phabricator-request		Details \| Review
Bug 1574002 - Add `wasmDis(func)` testing function for viewing disassembly of Wasm exported function. r?lth 6 years ago Ryan Hunt [:rhunt] 47 bytes, text/x-phabricator-request		Details \| Review

Ryan Hunt [:rhunt]

Assignee

Description

•

6 years ago

Through debugging Wasm codegen I've used IONFLAGS=codegen to view the generated assembly. It's really noisy though, and it seemed useful to be able to wasmDis(wasmFunc) so I wrote a patch to be able to do this.

I'm unsure whether this is useful for other people, so this bug is just to solicit opinions.

Example: (IONFLAGS is filtered)

js> let fib = wasmRun('fib.wat').instance.exports.fib;
[Codegen] # ========================================
[Codegen] # Emitting wasm baseline code
[Codegen] # beginFunction: start of function prologue for index 1
[Codegen] [6] 71008d5f        cmp     w10, #0x23 (35)
[Codegen] [6] 54000000        b.eq    -> 1000f
[Codegen] [6] d45bd600        hlt     #0xdeb0
[Codegen] [6]           1000:
[Codegen] [6] d10083ff        sub     sp, sp, #0x20 (32)
[Codegen] [6] f9000ffe        str     x30, [sp, #24]
[Codegen] [6] f90007f7        str     x23, [sp, #8]
[Codegen] [6] f90003fd        str     x29, [sp]
[Codegen] [6] 910003fd        mov     x29, sp
[Codegen] [6] d2800010        mov     x16, #0x0
[Codegen] [6] f2a00010        movk    x16, #0x0, lsl #16
[Codegen] [6] cb3063e8        sub     x8, sp, x16
[Codegen] [6] f94016f0        ldr     x16, [x23, #40]
[Codegen] [6] eb08021f        cmp     x16, x8
[Codegen] [6] 54000003        b.lo    -> 1001f
[Codegen] [6] d45bd600        hlt     #0xdeb0
[Codegen] [6]           1001:
[Codegen] [6] d10143ff        sub     sp, sp, #0x50 (80)
[Codegen] [6] b9004fe0        str     w0, [sp, #76]
[Codegen] # beginFunction: enter body with masm.framePushed = 80
[Codegen] [6] b9404fe0        ldr     w0, [sp, #76]
[Codegen] [6] 7100041f        cmp     w0, #0x1 (1)
[Codegen] [6] 54000008        b.hi    -> 1002f
[Codegen] [6] 52800020        mov     w0, #0x1
[Codegen] [6] 14000000        b       -> 1003f
[Codegen] [6]           1002:
[Codegen] [6] b9404fe0        ldr     w0, [sp, #76]
[Codegen] [6] 51000400        sub     w0, w0, #0x1 (1)
[Codegen] [6] f9001fe0        str     x0, [sp, #56]
[Codegen] [6] b9403be0        ldr     w0, [sp, #56]
[Codegen] [6] f9402ff7        ldr     x23, [sp, #88]
[Codegen] [6] 94000000        bl      #+0x0 (addr 0x11631f0b8)-> (link-time target)
[Codegen] [6] b9404fe1        ldr     w1, [sp, #76]
[Codegen] [6] 51000821        sub     w1, w1, #0x2 (2)
[Codegen] [6] f9001fe0        str     x0, [sp, #56]
[Codegen] [6] f9001be1        str     x1, [sp, #48]
[Codegen] [6] b94033e0        ldr     w0, [sp, #48]
[Codegen] [6] f9402ff7        ldr     x23, [sp, #88]
[Codegen] [6] 94000000        bl      #+0x0 (addr 0x11631f0d4)-> (link-time target)
[Codegen] [6] f9401fe1        ldr     x1, [sp, #56]
[Codegen] [6] 0b000021        add     w1, w1, w0
[Codegen] [6] 2a0103e0        mov     w0, w1
[Codegen] [6] 17ffffef        b       -> 1003f
[Codegen] # endFunction: start of function epilogue
[Codegen] [6] d4200000        brk     #0x0
[Codegen] [6]           1003:
[Codegen] [6] 910143ff        add     sp, sp, #0x50 (80)
[Codegen] [6] f94003fd        ldr     x29, [sp]
[Codegen] [6] f94007f7        ldr     x23, [sp, #8]
[Codegen] [6] f9400ffe        ldr     x30, [sp, #24]
[Codegen] [6] 910083ff        add     sp, sp, #0x20 (32)
[Codegen] [6] d65f03c0        ret
[Codegen] # endFunction: end of function epilogue
[Codegen] # endFunction: start of OOL code
[Codegen] # endFunction: end of OOL code for index 1
8
js> wasmDis(fib)
0x27d6e95c3090  71008d5f  cmp     w10, #0x23 (35)
0x27d6e95c3094  540000e0  b.eq    #+0x1c (addr 0x27d6e95c30b0)
0x27d6e95c3098  d45bd600  hlt     #0xdeb0
0x27d6e95c309c  14000003  b       #+0xc (addr 0x27d6e95c30a8)
0x27d6e95c30a0  ffff0001  unallocated (Unallocated)
0x27d6e95c30a4  14000003  b       #+0xc (addr 0x27d6e95c30b0)
0x27d6e95c30a8  d503201f  nop
0x27d6e95c30ac  d503201f  nop
0x27d6e95c30b0  d10083ff  sub     sp, sp, #0x20 (32)
0x27d6e95c30b4  f9000ffe  str     x30, [sp, #24]
0x27d6e95c30b8  f90007f7  str     x23, [sp, #8]
0x27d6e95c30bc  f90003fd  str     x29, [sp]
0x27d6e95c30c0  910003fd  mov     x29, sp
0x27d6e95c30c4  d2800a10  mov     x16, #0x50
0x27d6e95c30c8  f2a00010  movk    x16, #0x0, lsl #16
0x27d6e95c30cc  cb3063e8  sub     x8, sp, x16
0x27d6e95c30d0  f94016f0  ldr     x16, [x23, #40]
0x27d6e95c30d4  eb08021f  cmp     x16, x8
0x27d6e95c30d8  54000043  b.lo    #+0x8 (addr 0x27d6e95c30e0)
0x27d6e95c30dc  d45bd600  hlt     #0xdeb0
0x27d6e95c30e0  d10143ff  sub     sp, sp, #0x50 (80)
0x27d6e95c30e4  b9004fe0  str     w0, [sp, #76]
0x27d6e95c30e8  b9404fe0  ldr     w0, [sp, #76]
0x27d6e95c30ec  7100041f  cmp     w0, #0x1 (1)
0x27d6e95c30f0  54000068  b.hi    #+0xc (addr 0x27d6e95c30fc)
0x27d6e95c30f4  52800020  mov     w0, #0x1
0x27d6e95c30f8  14000013  b       #+0x4c (addr 0x27d6e95c3144)
0x27d6e95c30fc  b9404fe0  ldr     w0, [sp, #76]
0x27d6e95c3100  51000400  sub     w0, w0, #0x1 (1)
0x27d6e95c3104  f9001fe0  str     x0, [sp, #56]
0x27d6e95c3108  b9403be0  ldr     w0, [sp, #56]
0x27d6e95c310c  f9402ff7  ldr     x23, [sp, #88]
0x27d6e95c3110  97ffffe8  bl      #-0x60 (addr 0x27d6e95c30b0)
0x27d6e95c3114  b9404fe1  ldr     w1, [sp, #76]
0x27d6e95c3118  51000821  sub     w1, w1, #0x2 (2)
0x27d6e95c311c  f9001fe0  str     x0, [sp, #56]
0x27d6e95c3120  f9001be1  str     x1, [sp, #48]
0x27d6e95c3124  b94033e0  ldr     w0, [sp, #48]
0x27d6e95c3128  f9402ff7  ldr     x23, [sp, #88]
0x27d6e95c312c  97ffffe1  bl      #-0x7c (addr 0x27d6e95c30b0)
0x27d6e95c3130  f9401fe1  ldr     x1, [sp, #56]
0x27d6e95c3134  0b000021  add     w1, w1, w0
0x27d6e95c3138  2a0103e0  mov     w0, w1
0x27d6e95c313c  14000002  b       #+0x8 (addr 0x27d6e95c3144)
0x27d6e95c3140  d4200000  brk     #0x0
0x27d6e95c3144  910143ff  add     sp, sp, #0x50 (80)
0x27d6e95c3148  f94003fd  ldr     x29, [sp]
0x27d6e95c314c  f94007f7  ldr     x23, [sp, #8]
0x27d6e95c3150  f9400ffe  ldr     x30, [sp, #24]
0x27d6e95c3154  910083ff  add     sp, sp, #0x20 (32)
0x27d6e95c3158  d65f03c0  ret

Ryan Hunt [:rhunt]

Assignee

Comment 1

•

6 years ago

Attached file Bug 1574002 - Add jit::Disassemble as a wrapper around existing in-tree disassemblers. r?lth — Details

Lars T Hansen [:lth]

Comment 2

•

6 years ago

Seems useful to me. Too bad about the disappearing labels, but I guess the addresses work out OK.

Ryan Hunt [:rhunt]

Assignee

Comment 3

•

6 years ago

Okay. The only controversial change might be building Zydis even if Cranelift isn't enabled so that this works on x86/x64. But if it's still behind a #ifdef JS_JITSPEW that might not affect too many people?

Either way, I'll polish up the patch a bit and put it up for review.

Ryan Hunt [:rhunt]

Assignee

Comment 4

•

6 years ago

https://treeherder.mozilla.org/#/jobs?repo=try&revision=54e5151e89a946cce6b36aeb2d1f7f1c4dcee099

Ryan Hunt [:rhunt]

Assignee

Comment 5

•

6 years ago

Attached file Bug 1574002 - Build Zydis even when not using Cranelift. r?lth — Details

The #ifdef(JS_JITSPEW) restriction is still kept.

Phabricator Automation

Updated

•

6 years ago

Attachment #9085622 - Attachment description: Bug 1574002 - Wasm: Add jit::Disassemble and use it for wasmDis function. → Bug 1574002 - Add jit::Disassemble as a wrapper around existing in-tree disassemblers. r?lth

Ryan Hunt [:rhunt]

Assignee

Comment 6

•

6 years ago

Attached file Bug 1574002 - Use jit::Disassemble for Cranelift JitSpew. r?lth — Details

Depends on D42052

Ryan Hunt [:rhunt]

Assignee

Comment 7

•

6 years ago

Attached file Bug 1574002 - Add `wasmDis(func)` testing function for viewing disassembly of Wasm exported function. r?lth — Details

Depends on D42223

Lars T Hansen [:lth]

Updated

•

6 years ago

Priority: -- → P3

Lars T Hansen [:lth]

Comment 8

•

6 years ago

Yeah, behind the JS_JITSPEW flag should be just fine.

Pulsebot

Comment 9

•

6 years ago

Pushed by rhunt@eqrion.net: https://hg.mozilla.org/integration/autoland/rev/7e315ddebb02 Build Zydis even when not using Cranelift. r=lth https://hg.mozilla.org/integration/autoland/rev/9f6b91a72f1f Add jit::Disassemble as a wrapper around existing in-tree disassemblers. r=lth https://hg.mozilla.org/integration/autoland/rev/3807af5c121a Use jit::Disassemble for Cranelift JitSpew. r=lth https://hg.mozilla.org/integration/autoland/rev/ac0c1beee54f Add `wasmDis(func)` testing function for viewing disassembly of Wasm exported function. r=lth

Arthur Iakab [arthur_iakab]

Comment 10

•

6 years ago

Backed out 4 changesets (bug 1574002) for causing spidermonkey bustage on Disassemble.h CLOSED TREE

Backout revision https://hg.mozilla.org/integration/autoland/rev/9c344fdaa44483e5ca18d343ac5fb4af7c0e0127

Failed push https://treeherder.mozilla.org/#/jobs?repo=autoland&selectedJob=262320183&revision=ac0c1beee54f49efc49237a994acc7c63bf6fb7f&searchStr=linux%2Cx64%2Cdebug%2Cspidermonkey%2Cbuilds%2Cspidermonkey-sm-nonunified-linux64%2Fdebug%2Csm%28nu%29

Failure log https://treeherder.mozilla.org/logviewer.html#?job_id=262320183&repo=autoland

Ryan can you please take a look?

Flags: needinfo?(rhunt)

Pulsebot

Comment 11

•

6 years ago

Pushed by rhunt@eqrion.net: https://hg.mozilla.org/integration/autoland/rev/7ed2f4ec0cc2 Build Zydis even when not using Cranelift. r=lth https://hg.mozilla.org/integration/autoland/rev/6d1f82ea2d92 Add jit::Disassemble as a wrapper around existing in-tree disassemblers. r=lth https://hg.mozilla.org/integration/autoland/rev/b4ca080d3c7b Use jit::Disassemble for Cranelift JitSpew. r=lth https://hg.mozilla.org/integration/autoland/rev/3eb184cc45d5 Add `wasmDis(func)` testing function for viewing disassembly of Wasm exported function. r=lth

Ryan Hunt [:rhunt]

Assignee

Comment 12

•

6 years ago

Non-unified bustage, should be fixed.

Flags: needinfo?(rhunt)

Alexandru Michis [:malexandru]

Comment 13

•

6 years ago

bugherder

https://hg.mozilla.org/mozilla-central/rev/7ed2f4ec0cc2
https://hg.mozilla.org/mozilla-central/rev/6d1f82ea2d92
https://hg.mozilla.org/mozilla-central/rev/b4ca080d3c7b
https://hg.mozilla.org/mozilla-central/rev/3eb184cc45d5

Status: NEW → RESOLVED

Closed: 6 years ago

status-firefox70: --- → fixed

Resolution: --- → FIXED

Target Milestone: --- → mozilla70

BugBot [:suhaib / :marco/ :calixte]

Updated

•

6 years ago

Assignee: nobody → rhunt

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Bugzilla

Add method to programmatically view disassembly of Wasm exported function

Categories

(Core :: JavaScript: WebAssembly, enhancement, P3)

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()

People

(Reporter: rhunt, Assigned: rhunt)

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(public)

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Attachments

(4 files)

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Comment 1

Comment 2

Comment 3

Comment 4

Comment 5

Updated

Comment 6

Comment 7

Updated

Comment 8

Comment 9

Comment 10

Comment 11

Comment 12

Comment 13

Updated

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