Closed Bug 607864 Opened 15 years ago Closed 15 years ago

TM: systematically annotate bytecode boundaries in LIR dumps

Categories

(Core :: JavaScript Engine, defect)

Product:
Core
Component:
JavaScript Engine
Platform:
x86
macOS
Type:
defect
Priority:
Not set
Severity:
normal

Tracking

()

Status:
RESOLVED FIXED

People

(Reporter: n.nethercote, Assigned: n.nethercote)

Details

(Whiteboard: fixed-in-tracemonkey)

Attachments

(1 file)

patch (against TM 56425:6b9f7d6cd601)
3.25 KB, patch
dmandelin
: review+
Details | Diff | Splinter Review
Bug 607244 added the LIR_comment bytecode, and applied it in a handful of places in TM. This patch applies it in a much more systematic fashion -- one per bytecode. Here's an example of the TMFLAGS=recorder output. Since bug 607555 fixed the bytecode/LIR interleaving the extra comments are redundant: 00094: 155 getlocal 1 ------------------------------ # JSOP_GETLOCAL $stack6 = ldi.sp sp[-32] sti.sp sp[0] = $stack6 00097: 155 getlocal 3 ------------------------------ # JSOP_GETLOCAL sti.sp sp[8] = ldi2 00100: 155 getarg 0 ------------------------------ # JSOP_GETARG sti.sp sp[16] = $stack2 00103: 155 int8 2 ------------------------------ # JSOP_INT8 sti.sp sp[24] = immi1/*2*/ 00105: 155 getlocal 3 ------------------------------ # JSOP_GETLOCAL sti.sp sp[32] = ldi2 00108: 155 mul ------------------------------ # JSOP_MUL About to try emitting guard_xov code for SideExit=0x8e79044 exitType=OVERFLOW sti.sp sp[24] = mulxovi1 00109: 155 one ------------------------------ # JSOP_ONE immd2 = immd 1 immi3 = immi 1 sti.sp sp[32] = immi3/*1*/ 00110: 155 add ------------------------------ # JSOP_ADD About to try emitting guard_xov code for SideExit=0x8e79094 exitType=OVERFLOW addxovi1 = addxovi mulxovi1, immi3/*1*/ -> pc=0x8e43b0a imacpc=(nil) sp+40 rp+0 (GuardID=010) i2d2 = i2d addxovi1 sti.sp sp[24] = addxovi1 00111: 155 getelem ------------------------------ # JSOP_GETELEM capacity3 = ldi.objcapacity $stack2[32] ltui4 = ltui addxovi1, capacity3 xf6: xf ltui4 -> pc=0x8e43b0b imacpc=(nil) sp+32 rp+0 (GuardID=012) lshi3 = lshi addxovi1, immi2/*3*/ slots3 = ldi.objslots $stack2[36] addi3 = addi slots3, lshi3 ldi7 = ldi.slots addi3[4] ltui5 = ltui ldi7, JSVAL_TAG_CLEAR/*0xffff0000*/ xf7: xf ltui5 -> pc=0x8e43b0b imacpc=(nil) sp+32 rp+0 (GuardID=013) ldd2 = ldd.slots addi3[0] std.sp sp[16] = ldd2 However, the new comments are much more useful in the TMFLAGS=afterdce dumps: ------------------------------ # JSOP_GETLOCAL $stack6 = ldi.sp sp[-32] sti.sp sp[0] = $stack6 ------------------------------ # JSOP_GETLOCAL sti.sp sp[8] = ldi2 ------------------------------ # JSOP_GETARG sti.sp sp[16] = $stack2 ------------------------------ # JSOP_INT8 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL sti.sp sp[24] = mulxovi1 ------------------------------ # JSOP_ONE immi3 = immi 1 sti.sp sp[32] = immi3/*1*/ ------------------------------ # JSOP_ADD addxovi1 = addxovi mulxovi1, immi3/*1*/ -> pc=0x8e43b0a imacpc=(nil) sp+40 rp+0 (GuardID=010) sti.sp sp[24] = addxovi1 ------------------------------ # JSOP_GETELEM capacity3 = ldi.objcapacity $stack2[32] ltui4 = ltui addxovi1, capacity3 xf6: xf ltui4 -> pc=0x8e43b0b imacpc=(nil) sp+32 rp+0 (GuardID=012) lshi3 = lshi addxovi1, immi2/*3*/ slots3 = ldi.objslots $stack2[36] addi3 = addi slots3, lshi3 ldi7 = ldi.slots addi3[4] ltui5 = ltui ldi7, JSVAL_TAG_CLEAR/*0xffff0000*/ xf7: xf ltui5 -> pc=0x8e43b0b imacpc=(nil) sp+32 rp+0 (GuardID=013) ldd2 = ldd.slots addi3[0] std.sp sp[16] = ldd2 It makes the 'afterdce' dumps as easy to read as the 'recorder' ones, which I think is definitely worth doing even if adds some redundant info in the 'recorder' ones. It's particularly helpful when bytecodes end up having no LIR due to StackFilter and dead-code-elimination. I'll stop fiddling with LIR dumps after this bug, I promise :)
Attachment #486549 - Flags: review?(dmandelin)
I was just looking at some Kraken LIR dumps, this is *really* nice. It particularly gives you a good idea how good the LIR is. For example, in imaging-darkroom, lots of bytecodes end up translated to a single LIR instruction, which shows that things are working really well.
Brendan asked for an example. Here is a portion from the hottest loop of imaging-darkroom-data.js, line 77, which contains a lot of double arithmetic: ------------------------------ # JSOP_DOUBLE immd5 = immd 0.299 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL muld4 = muld muld1, immd5/*0.299*/ ------------------------------ # JSOP_DOUBLE immd6 = immd 0.587 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL muld5 = muld muld2, immd6/*0.587*/ ------------------------------ # JSOP_ADD addd1 = addd muld4, muld5 ------------------------------ # JSOP_DOUBLE immd7 = immd 0.114 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL muld6 = muld muld3, immd7/*0.114*/ ------------------------------ # JSOP_ADD addd2 = addd addd1, muld6 ------------------------------ # JSOP_SETLOCAL std.sp sp[-24] = addd2 ------------------------------ # JSOP_DOUBLE immd8 = immd 0.596 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL muld7 = muld muld1, immd8/*0.596*/ ------------------------------ # JSOP_DOUBLE immd9 = immd 0.275 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL muld8 = muld muld2, immd9/*0.275*/ ------------------------------ # JSOP_SUB subd1 = subd muld7, muld8 ------------------------------ # JSOP_DOUBLE immd10 = immd 0.321 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL muld9 = muld muld3, immd10/*0.321*/ ------------------------------ # JSOP_SUB subd2 = subd subd1, muld9 ------------------------------ # JSOP_SETLOCAL ------------------------------ # JSOP_DOUBLE immd11 = immd 0.212 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL muld10 = muld muld1, immd11/*0.212*/ ------------------------------ # JSOP_DOUBLE immd12 = immd 0.523 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_MUL muld11 = muld muld2, immd12/*0.523*/ ------------------------------ # JSOP_SUB subd3 = subd muld10, muld11
Another example for Brendan, where many JSOPs turn into a single LIR instruction: ------------------------------ # JSOP_INT8 ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_ADD ------------------------------ # JSOP_GETGNAME ------------------------------ # JSOP_MUL ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_GETLOCAL ------------------------------ # JSOP_ADD ------------------------------ # JSOP_ADD ------------------------------ # JSOP_MUL sti.sp sp[16] = mulxovi2 This is thanks to CSE -- the same expression was computed earlier.
Comment on attachment 486549 [details] [diff] [review] patch (against TM 56425:6b9f7d6cd601) It's about time x became op.
Attachment #486549 - Flags: review?(dmandelin) → review+
http://hg.mozilla.org/tracemonkey/rev/e29367700eec
Whiteboard: fixed-in-tracemonkey
http://hg.mozilla.org/mozilla-central/rev/e29367700eec
Status: ASSIGNED → RESOLVED
Closed: 15 years ago
Resolution: --- → FIXED
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