code *nteh_unwind(regm_t retregs,unsigned index)
{
code cs;
regm_t desregs;
int reg;
int local_unwind;
// Shouldn't this always be CX?
#if SCPP
reg = AX;
#else
reg = CX;
#endif
#if MARS
local_unwind = RTLSYM_D_LOCAL_UNWIND2;
#else
local_unwind = RTLSYM_LOCAL_UNWIND2;
#endif
desregs = (~getRtlsym(local_unwind)->Sregsaved & (ALLREGS)) | mask[reg];
code *cs1;
code *cs2;
gensaverestore(retregs & desregs,&cs1,&cs2);
CodeBuilder cdb(getregs(desregs));
cs.Iop = 0x8D;
cs.Irm = modregrm(2,reg,BPRM);
cs.Iflags = 0;
cs.Irex = 0;
cs.IFL1 = FLconst;
// EBP offset of __context.prev
cs.IEV1.Vint = nteh_EBPoffset_prev();
cdb.gen(&cs); // LEA ECX,contextsym
cdb.genc2(0x68,0,index); // PUSH index
cdb.gen1(0x50 + reg); // PUSH ECX
#if MARS
//cdb.gencs(0xB8+AX,0,FLextern,nteh_scopetable()); // MOV EAX,&scope_table
cdb.gencs(0x68,0,FLextern,nteh_scopetable()); // PUSH &scope_table
cdb.gencs(0xE8,0,FLfunc,getRtlsym(local_unwind)); // CALL __d_local_unwind2()
cdb.append(cod3_stackadj(NULL, -12));
#else
cdb.gencs(0xE8,0,FLfunc,getRtlsym(local_unwind)); // CALL __local_unwind2()
cdb.append(cod3_stackadj(NULL, -8));
#endif
CodeBuilder cdb1(cs1);
CodeBuilder cdb2(cs2);
cdb1.append(cdb, cdb2);
return cdb1.finish();
}
code *nteh_unwind(regm_t retregs,unsigned index)
{ code *c;
code cs;
code *cs1;
code *cs2;
regm_t desregs;
int reg;
int local_unwind;
// Shouldn't this always be CX?
#if SCPP
reg = AX;
#else
reg = CX;
#endif
#if MARS
local_unwind = RTLSYM_D_LOCAL_UNWIND2;
#else
local_unwind = RTLSYM_LOCAL_UNWIND2;
#endif
desregs = (~getRtlsym(local_unwind)->Sregsaved & (ALLREGS)) | mask[reg];
gensaverestore(retregs & desregs,&cs1,&cs2);
c = getregs(desregs);
cs.Iop = 0x8D;
cs.Irm = modregrm(2,reg,BPRM);
cs.Iflags = 0;
cs.Irex = 0;
cs.IFL1 = FLconst;
// EBP offset of __context.prev
cs.IEV1.Vint = nteh_EBPoffset_prev();
c = gen(c,&cs); // LEA ECX,contextsym
genc2(c,0x68,0,index); // PUSH index
gen1(c,0x50 + reg); // PUSH ECX
#if MARS
//gencs(c,0xB8+AX,0,FLextern,nteh_scopetable()); // MOV EAX,&scope_table
gencs(c,0x68,0,FLextern,nteh_scopetable()); // PUSH &scope_table
gencs(c,0xE8,0,FLfunc,getRtlsym(local_unwind)); // CALL __d_local_unwind2()
cod3_stackadj(c, -12);
#else
gencs(c,0xE8,0,FLfunc,getRtlsym(local_unwind)); // CALL __local_unwind2()
cod3_stackadj(c, -8);
#endif
c = cat4(cs1,c,cs2,NULL);
return c;
}
code *linux_unwind(regm_t retregs,unsigned index)
{
int i;
regm_t desregs;
int reg;
int local_unwind;
// Shouldn't this always be CX?
#if SCPP
reg = AX;
#else
reg = CX;
#endif
#if MARS
local_unwind = RTLSYM_D_LOCAL_UNWIND2;
#else
local_unwind = RTLSYM_LOCAL_UNWIND2;
#endif
desregs = (~getRtlsym(local_unwind)->Sregsaved & (ALLREGS)) | mask[reg];
code *cs1;
code *cs2;
gensaverestore(retregs & desregs,&cs1,&cs2);
CodeBuilder cdb(getregs(desregs));
cdb.genc2(0x68,0,index); // PUSH index
#if MARS
// cdb.gencs(0x68,0,FLextern,nteh_scopetable()); // PUSH &scope_table
cdb.gencs(0xE8,0,FLfunc,getRtlsym(local_unwind)); // CALL __d_local_unwind2()
cdb.append(cod3_stackadj(NULL, -4));
#else
cdb.gencs(0xE8,0,FLfunc,getRtlsym(local_unwind)); // CALL __local_unwind2()
cdb.append(cod3_stackadj(NULL, -8));
#endif
CodeBuilder cdb1(cs1);
CodeBuilder cdb2(cs2);
cdb1.append(cdb, cdb2);
return cdb1.finish();
}
code *linux_unwind(regm_t retregs,unsigned index)
{ code *c;
code *cs1;
code *cs2;
int i;
regm_t desregs;
int reg;
int local_unwind;
// Shouldn't this always be CX?
#if SCPP
reg = AX;
#else
reg = CX;
#endif
#if MARS
local_unwind = RTLSYM_D_LOCAL_UNWIND2;
#else
local_unwind = RTLSYM_LOCAL_UNWIND2;
#endif
desregs = (~getRtlsym(local_unwind)->Sregsaved & (ALLREGS)) | mask[reg];
gensaverestore(retregs & desregs,&cs1,&cs2);
c = getregs(desregs);
c = genc2(c,0x68,0,index); // PUSH index
#if MARS
// gencs(c,0x68,0,FLextern,nteh_scopetable()); // PUSH &scope_table
gencs(c,0xE8,0,FLfunc,getRtlsym(local_unwind)); // CALL __d_local_unwind2()
cod3_stackadj(c, -4);
#else
gencs(c,0xE8,0,FLfunc,getRtlsym(local_unwind)); // CALL __local_unwind2()
cod3_stackadj(c, -8);
#endif
c = cat4(cs1,c,cs2,NULL);
return c;
}
code *cdsetjmp(elem *e,regm_t *pretregs)
{ code cs;
code *c;
regm_t retregs;
unsigned stackpushsave;
unsigned flag;
c = NULL;
stackpushsave = stackpush;
#if SCPP
if (CPP && (funcsym_p->Sfunc->Fflags3 & Fcppeh || usednteh & NTEHcpp))
{
/* If in C++ try block
If the frame that is calling setjmp has a try,catch block then
the call to setjmp3 is as follows:
__setjmp3(environment,3,__cpp_longjmp_unwind,trylevel,funcdata);
__cpp_longjmp_unwind is a routine in the RTL. This is a
stdcall routine that will deal with unwinding for CPP Frames.
trylevel is the value that gets incremented at each catch,
constructor invocation.
funcdata is the same value that you put into EAX prior to
cppframehandler getting called.
*/
symbol *s;
s = except_gensym();
if (!s)
goto L1;
c = gencs(c,0x68,0,FLextern,s); // PUSH &scope_table
stackpush += 4;
genadjesp(c,4);
c = genc1(c,0xFF,modregrm(1,6,BP),FLconst,(targ_uns)-4);
// PUSH trylevel
stackpush += 4;
genadjesp(c,4);
cs.Iop = 0x68;
cs.Iflags = CFoff;
cs.Irex = 0;
cs.IFL2 = FLextern;
cs.IEVsym2 = getRtlsym(RTLSYM_CPP_LONGJMP);
cs.IEVoffset2 = 0;
c = gen(c,&cs); // PUSH &_cpp_longjmp_unwind
stackpush += 4;
genadjesp(c,4);
flag = 3;
}
else
#endif
if (funcsym_p->Sfunc->Fflags3 & Fnteh)
{
/* If in NT SEH try block
If the frame that is calling setjmp has a try, except block
then the call to setjmp3 is as follows:
__setjmp3(environment,2,__seh_longjmp_unwind,trylevel);
__seth_longjmp_unwind is supplied by the RTL and is a stdcall
function. It is the name that MSOFT uses, we should
probably use the same one.
trylevel is the value that you increment at each try and
decrement at the close of the try. This corresponds to the
index field of the ehrec.
*/
int sindex_off;
sindex_off = 20; // offset of __context.sindex
cs.Iop = 0xFF;
cs.Irm = modregrm(2,6,BPRM);
cs.Iflags = 0;
cs.Irex = 0;
cs.IFL1 = FLbprel;
cs.IEVsym1 = nteh_contextsym();
cs.IEVoffset1 = sindex_off;
c = gen(c,&cs); // PUSH scope_index
stackpush += 4;
genadjesp(c,4);
cs.Iop = 0x68;
cs.Iflags = CFoff;
cs.Irex = 0;
cs.IFL2 = FLextern;
cs.IEVsym2 = getRtlsym(RTLSYM_LONGJMP);
cs.IEVoffset2 = 0;
c = gen(c,&cs); // PUSH &_seh_longjmp_unwind
stackpush += 4;
genadjesp(c,4);
flag = 2;
}
else
{
/* If the frame calling setjmp has neither a try..except, nor a
try..catch, then call setjmp3 as follows:
_setjmp3(environment,0)
*/
L1:
flag = 0;
}
cs.Iop = 0x68;
cs.Iflags = 0;
cs.Irex = 0;
cs.IFL2 = FLconst;
cs.IEV2.Vint = flag;
c = gen(c,&cs); // PUSH flag
stackpush += 4;
genadjesp(c,4);
c = cat(c,pushParams(e->E1,REGSIZE));
c = cat(c,getregs(~getRtlsym(RTLSYM_SETJMP3)->Sregsaved & (ALLREGS | mES)));
gencs(c,0xE8,0,FLfunc,getRtlsym(RTLSYM_SETJMP3)); // CALL __setjmp3
c = cod3_stackadj(c, -(stackpush - stackpushsave));
genadjesp(c,-(stackpush - stackpushsave));
stackpush = stackpushsave;
retregs = regmask(e->Ety, TYnfunc);
return cat(c,fixresult(e,retregs,pretregs));
}
code *nteh_prolog()
{
code cs;
code *c1;
code *c;
if (usednteh & NTEHpassthru)
{
/* An sindex value of -2 is a magic value that tells the
* stack unwinder to skip this frame.
*/
assert(config.exe & (EX_LINUX | EX_LINUX64 | EX_OSX | EX_OSX64 | EX_FREEBSD | EX_FREEBSD64 | EX_SOLARIS | EX_SOLARIS64 | EX_OPENBSD | EX_OPENBSD64));
cs.Iop = 0x68;
cs.Iflags = 0;
cs.Irex = 0;
cs.IFL2 = FLconst;
cs.IEV2.Vint = -2;
return gen(CNIL,&cs); // PUSH -2
}
/* Generate instance of struct __nt_context on stack frame:
[ ] // previous ebp already there
push -1 // sindex
mov EDX,FS:__except_list
push offset FLAT:scope_table // stable (not for MARS or C++)
push offset FLAT:__except_handler3 // handler
push EDX // prev
mov FS:__except_list,ESP
sub ESP,8 // info, esp for __except support
*/
// useregs(mAX); // What is this for?
cs.Iop = 0x68;
cs.Iflags = 0;
cs.Irex = 0;
cs.IFL2 = FLconst;
cs.IEV2.Vint = -1;
c1 = gen(CNIL,&cs); // PUSH -1
if (MARS || (usednteh & NTEHcpp))
{
// PUSH &framehandler
cs.IFL2 = FLframehandler;
#if MARS
nteh_scopetable();
#endif
}
else
{
// Do stable
cs.Iflags |= CFoff;
cs.IFL2 = FLextern;
cs.IEVsym2 = nteh_scopetable();
cs.IEVoffset2 = 0;
c1 = gen(c1,&cs); // PUSH &scope_table
cs.IFL2 = FLextern;
cs.IEVsym2 = getRtlsym(RTLSYM_EXCEPT_HANDLER3);
makeitextern(getRtlsym(RTLSYM_EXCEPT_HANDLER3));
}
c = gen(NULL,&cs); // PUSH &__except_handler3
if (config.exe == EX_WIN32)
{
makeitextern(getRtlsym(RTLSYM_EXCEPT_LIST));
#if 0
cs.Iop = 0xFF;
cs.Irm = modregrm(0,6,BPRM);
cs.Iflags = CFfs;
cs.Irex = 0;
cs.IFL1 = FLextern;
cs.IEVsym1 = getRtlsym(RTLSYM_EXCEPT_LIST);
cs.IEVoffset1 = 0;
gen(c,&cs); // PUSH FS:__except_list
#else
useregs(mDX);
cs.Iop = 0x8B;
cs.Irm = modregrm(0,DX,BPRM);
cs.Iflags = CFfs;
cs.Irex = 0;
cs.IFL1 = FLextern;
cs.IEVsym1 = getRtlsym(RTLSYM_EXCEPT_LIST);
cs.IEVoffset1 = 0;
gen(c1,&cs); // MOV EDX,FS:__except_list
gen1(c,0x50 + DX); // PUSH EDX
#endif
cs.Iop = 0x89;
NEWREG(cs.Irm,SP);
gen(c,&cs); // MOV FS:__except_list,ESP
}
c = cod3_stackadj(c, 8);
return cat(c1,c);
}