515551 - FIX_FPU should depend on __i386__ not __i486__

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Graydon Hoare :graydon]

Attachment: Enable FIX_FPU instruction sequence anywhere we have __GNUC__ and __i386__

I figured that any __GNUC__ compiler generating x87 instructions would define __i486__ -- mine all do -- but I guess I was wrong.

If accepted, this patch will fault with an invalid instruction if you try to initialize spidermonkey -- note, spidermonkey itself, not just tracemonkey -- on an x87-less x86 machine. If you can still find one of those, buried in cobwebs. Otherwise it just extends the FIX_FPU clobber to work in cases with surprising compiler definitions.

Comment 1

[Brendan Eich [:brendan]]

Comment on attachment 399651 [details] [diff] [review]
Enable FIX_FPU instruction sequence anywhere we have __GNUC__ and __i386__

I'm clearly not adding much value here, but r=me.

/be

Comment 2

[Graydon Hoare :graydon]

I thought you might care that there's a possibly-new cpu/arch combo that might not start up spidermonkey. If not, I'll carry on.

Comment 3

[Graydon Hoare :graydon]

http://hg.mozilla.org/tracemonkey/rev/6599bfa8ea11

Comment 4

[Blake Kaplan (:mrbkap) (inactive)]

http://hg.mozilla.org/mozilla-central/rev/6599bfa8ea11

Comment 5

[Robert Sayre]

http://hg.mozilla.org/releases/mozilla-1.9.2/rev/2780062a0ce3