refactor: remove redundant CFG2seh from backend

src/backend/backconfig.c

@@ -84,7 +84,6 @@ void out_config_init(
     {
         config.exe = EX_WIN32;
         config.ehmethod = EH_WIN32;
-        config.flags2 |= CFG2seh;       // Win32 eh
         config.objfmt = mscoff ? OBJ_MSCOFF : OBJ_OMF;
     }
 

src/backend/cdef.h

@@ -754,7 +754,6 @@ struct Config
 #define CFG2noobj       0x1000  // we are not generating a .OBJ file
 #define CFG2noerrmax    0x4000  // no error count maximum
 #define CFG2expand      0x8000  // expanded output to list file
-#define CFG2seh         0x10000 // use Win32 SEH to support any exception handling
 #define CFG2stomp       0x20000 // enable stack stomping code
 #define CFG2gms         0x40000 // optimize debug symbols for microsoft debuggers
 #define CFGX2   (CFG2warniserr | CFG2phuse | CFG2phgen | CFG2phauto | \

src/backend/cgcod.c

@@ -184,7 +184,7 @@ void codgen()
 #else
     if (CPP)
     {
-        if (config.flags2 & CFG2seh &&
+        if (config.exe == EX_WIN32 &&
             (funcsym_p->Stype->Tflags & TFemptyexc || funcsym_p->Stype->Texcspec))
             usednteh |= NTEHexcspec;
         except_reset();
@@ -438,7 +438,7 @@ void codgen()
 
 #if SCPP
             if (CPP &&
-                !(config.flags2 & CFG2seh))
+                !(config.exe == EX_WIN32))
             {
                 //printf("b = %p, index = %d\n",b,b->Bindex);
                 //except_index_set(b->Bindex);
@@ -675,7 +675,7 @@ code *prolog()
         /* The exception stack unwinding mechanism relies on the EBP chain being intact,
          * so need frame if function can possibly throw
          */
-        !(config.flags2 & CFG2seh) && !(funcsym_p->Sfunc->Fflags3 & Fnothrow) ||
+        !(config.exe == EX_WIN32) && !(funcsym_p->Sfunc->Fflags3 & Fnothrow) ||
         sv64
        )
         needframe = 1;
@@ -1499,7 +1499,7 @@ STATIC void cgcod_eh()
                     case ESCdtor:
 //printf("ESCdtor\n");
                         except_pop(c,c->IEV1.Vtor,NULL);
-                    L1: if (config.flags2 & CFG2seh)
+                    L1: if (config.exe == EX_WIN32)
                         {
                             c1 = nteh_gensindex(except_index_get() - 1);
                             code_next(c1) = code_next(c);
@@ -1518,7 +1518,7 @@ STATIC void cgcod_eh()
                         list_pop(&stack);
                         if (idx != except_index_get())
                         {
-                            if (config.flags2 & CFG2seh)
+                            if (config.exe == EX_WIN32)
                             {   c1 = nteh_gensindex(idx - 1);
                                 code_next(c1) = code_next(c);
                                 code_next(c) = c1;
@@ -1586,7 +1586,7 @@ STATIC void cgcod_eh()
         }
     }
 
-    if (config.flags2 & CFG2seh)
+    if (config.exe == EX_WIN32)
         for (b = startblock; b; b = b->Bnext)
         {
             if (/*!b->Bcount ||*/ b->BC == BCtry)

src/backend/cod3.c

@@ -813,7 +813,7 @@ void outblkexitcode(block *bl, code*& c, int& anyspill, const char* sflsave, sym
 
         case BCtry:
             usednteh |= EHtry;
-            if (config.flags2 & CFG2seh)
+            if (config.exe == EX_WIN32)
                 usednteh |= NTEHtry;
             goto case_goto;
 #endif
@@ -841,7 +841,7 @@ void outblkexitcode(block *bl, code*& c, int& anyspill, const char* sflsave, sym
                     }
                 }
 #endif
-                if (config.flags2 & CFG2seh)
+                if (config.exe == EX_WIN32)
                     c = cat(c,nteh_unwind(0,toindex));
 #if MARS
                 else if (
@@ -906,7 +906,7 @@ void outblkexitcode(block *bl, code*& c, int& anyspill, const char* sflsave, sym
             goto L2;
 
         case BC_try:
-            if (config.flags2 & CFG2seh)
+            if (config.exe == EX_WIN32)
             {   usednteh |= NTEH_try;
                 nteh_usevars();
             }
@@ -1054,7 +1054,7 @@ void outblkexitcode(block *bl, code*& c, int& anyspill, const char* sflsave, sym
                         continue;
                     }
 #endif
-                    if (config.flags2 & CFG2seh)
+                    if (config.exe == EX_WIN32)
                     {
                         if (bt->Bscope_index == 0)
                         {
@@ -2974,7 +2974,7 @@ code* prolog_frame(unsigned farfunc, unsigned* xlocalsize, bool* enter)
         (*xlocalsize >= 0x1000 && config.exe & EX_flat) ||
         localsize >= 0x10000 ||
 #if NTEXCEPTIONS == 2
-        (usednteh & ~NTEHjmonitor && (config.flags2 & CFG2seh)) ||
+        (usednteh & ~NTEHjmonitor && (config.exe == EX_WIN32)) ||
 #endif
         (config.target_cpu >= TARGET_80386 &&
          config.flags4 & CFG4speed)
@@ -2988,7 +2988,7 @@ code* prolog_frame(unsigned farfunc, unsigned* xlocalsize, bool* enter)
             // Don't reorder instructions, as dwarf CFA relies on it
             code_orflag(c, CFvolatile);
 #if NTEXCEPTIONS == 2
-        if (usednteh & ~NTEHjmonitor && (config.flags2 & CFG2seh))
+        if (usednteh & ~NTEHjmonitor && (config.exe == EX_WIN32))
         {
             code *ce = nteh_prolog();
             c = cat(c,ce);

src/backend/nteh.c

@@ -59,7 +59,7 @@ int nteh_offset_info()          { return 4; }
 
 unsigned char *nteh_context_string()
 {
-    if (config.flags2 & CFG2seh)
+    if (config.exe == EX_WIN32)
         return (unsigned char *)text_nt;
     else
         return NULL;
@@ -408,7 +408,7 @@ code *nteh_prolog()
 
 code *nteh_epilog()
 {
-    if (!(config.flags2 & CFG2seh))
+    if (config.exe != EX_WIN32)
         return NULL;
 
     /* Generate:
@@ -542,7 +542,7 @@ code *nteh_patchindex(code* c, int sindex)
 code *nteh_gensindex(int sindex)
 {   code *c;
 
-    if (!(config.flags2 & CFG2seh))
+    if (config.exe != EX_WIN32)
         return NULL;
 
     // Generate:
@@ -813,7 +813,7 @@ code *nteh_monitor_prolog(Symbol *shandle)
     Symbol *s;
     regm_t desregs;
 
-    assert(config.flags2 & CFG2seh);    // BUG: figure out how to implement for other EX's
+    assert(config.exe == EX_WIN32);    // BUG: figure out how to implement for other EX's
 
     if (shandle->Sclass == SCfastpar)
     {   assert(shandle->Spreg != DX);
@@ -897,7 +897,7 @@ code *nteh_monitor_epilog(regm_t retregs)
     regm_t desregs;
     Symbol *s;
 
-    assert(config.flags2 & CFG2seh);    // BUG: figure out how to implement for other EX's
+    assert(config.exe == EX_WIN32);    // BUG: figure out how to implement for other EX's
 
     s = getRtlsym(RTLSYM_MONITOR_EPILOG);
     //desregs = ~s->Sregsaved & ALLREGS;

src/eh.c

@@ -251,7 +251,7 @@ void except_fillInEHTable(symbol *s)
             if (c->Iop == (ESCAPE | ESCdctor))
             {
                 code *c2 = code_next(c);
-                if (config.flags2 & CFG2seh)
+                if (config.ehmethod == EH_WIN32)
                     nteh_patchindex(c2, scopeindex);
                 if (config.ehmethod == EH_DM)
                     pdt = dtdword(pdt,boffset - startblock->Boffset); // guard offset
@@ -273,7 +273,7 @@ void except_fillInEHTable(symbol *s)
                         {
                             foffset = eoffset;
                             code *cf = code_next(c2);
-                            if (config.flags2 & CFG2seh)
+                            if (config.ehmethod == EH_WIN32)
                             {
                                 nteh_patchindex(cf, stack[stacki - 1]);
                                 foffset += calccodsize(cf);