On Wed, Mar 28, 2012 at 5:43 AM, Igor Stasenko <siguctua@gmail.com> wrote:

or perhaps not..
i am trying to build the cog cocoa VMs using configs made by Esteban..

CogCocoaIOSConfig new
" generateForDebug;"
generateForRelease;
addExternalPlugins: #( FT2Plugin );
addInternalPlugins: #( UnixOSProcessPlugin );
generateSources; generate.

it is not a functional bug.. because if i use #generateForDebug,
everything works fine (but slow ;)
but if i do #genearateForRelease, VM crashes with following:

Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x5eedca7a

0x5eedca7a = 5EEDCA5E + a little, one orf my bad hex puns. This is early in initialization in Cogit>compileClosedPICPrototype. 5EEDCA5E is used as a branch target in the PIC prototype. The concretize methods need to know whether a jump target is pointing to a fixup or is some real address to jump to. Look at the code generated for Cogit>addressIsInInstructions: in the various concretize methods for jumps. Looks like the optimizer is decidging that addressIsInInstructions: is always true.

e.g. what if you redefine Cogit>addressIsInInstructions: so that instead of

^self cCode: 'address >= (void *)&abstractOpcodes[0] && address < (void *)&abstractOpcodes[opcodeIndex]'

we use

^self cCode: '(unsigned long)(address) >= (unsigned long)&abstractOpcodes[0] && address < (unsigned long)&abstractOpcodes[opcodeIndex]'

HTH

Eliot

0x0000dfb6 in concretizeAt ()
(gdb) bt
#0 0x0000dfb6 in concretizeAt ()
#1 0x00014996 in generateInstructionsAt ()
#2 0x000000c9 in ?? ()

i am not sure how to squeeze more info about this crash point..
because stack trace is cut by gdb,
which /.another rant here./ stupidly stops scanning stack frames once
it discovers a frame which code is outside of memory covered by debug
information..

Ah.. yes.. and addition info.. the difference between generateForDebug
and generateForRelease

compilerFlagsRelease
^#(
"'-fobjc-direct-dispatch'"
'-msse3'
"'-msse4.1'"
"'-msse4.2'"
"'-mdynamic-no-pic'"
"'-fwritable-strings'"
'-Os'
'-fvisibility=hidden'
'-funroll-loops'
"'-fno-asm'"
'-fasm-blocks'
'-finline-functions'
'-mfpmath=sse'
'-fomit-frame-pointer'
'-march=pentium-m'
'-mtune=prescott'
'-falign-functions=16'
'-fno-gcse'
'-fno-cse-follow-jumps'
'-std=gnu99'
'-DBUILD_FOR_OSX'
'-DUSE_INLINE_MEMORY_ACCESSORS'
'-DLSB_FIRST'
'-DUSE_INLINE_MEMORY_ACCESSORS'
'-DHAVE_SYS_TIME_H'
'-DHAVE_NANOSLEEP'
'-DICC_DEBUG=0'
'-DICC_OPTLEVEL="speedHLO"'
'-DICC_OPT_IPO_FOR_SINGLE_FILE_COMPILATION=1'
'-DICC_OPT_PARALLEL=0'
'-DICC_OPT_PREFETCH_INSERTION=1'
'-DICC_OPT_PROVIDE_FRAME_PTR=0'
'-DICC_OPT_USE_ARCH_IA32="SSE42"')

compilerFlagsDebug
^#(
'-g3'
'-O0'
'-DDEBUGVM=1')

--
Best regards,
Igor Stasenko.