Dwarf EH: more fixes

src/backend/cc.h

@@ -729,6 +729,8 @@ typedef struct FUNC_S
     Symbol **typesTable;
     size_t typesTableDim;       // number used in typesTable[]
     size_t typesTableCapacity;  // allocated capacity of typesTable[]
+
+    unsigned LSDAoffset;        // offset in LSDA segment of the LSDA data for this function
 } func_t;
 
 #define func_calloc()   ((func_t *) mem_fcalloc(sizeof(func_t)))

src/backend/cod2.c

@@ -5122,7 +5122,7 @@ code *cdddtor(elem *e,regm_t *pretregs)
 
         assert(*pretregs == 0);
         code *c = codelem(e->E1,pretregs,FALSE);
-        return c;
+        return cat(cd, c);
     }
     else
     {

src/backend/cod3.c

@@ -3003,7 +3003,7 @@ code* prolog_frame(unsigned farfunc, unsigned* xlocalsize, bool* enter)
             dwarf_CFA_set_loc(1);           // address after PUSH EBP
             dwarf_CFA_set_reg_offset(SP, off); // CFA is now 8[ESP]
             dwarf_CFA_offset(BP, -off);       // EBP is at 0[ESP]
-            dwarf_CFA_set_loc(3);           // address after MOV EBP,ESP
+            dwarf_CFA_set_loc(I64 ? 4 : 3);   // address after MOV EBP,ESP
             // Yes, I know the parameter is 8 when we mean 0!
             // But this gets the cfa register set to EBP correctly
             dwarf_CFA_set_reg_offset(BP, off);        // CFA is now 0[EBP]

src/backend/dwarf.c

@@ -83,6 +83,18 @@ int dwarf_getsegment(const char *name, int align)
 #endif
 }
 
+int dwarf_getsegment_alloc(const char *name, int align)
+{
+#if ELFOBJ
+    return ElfObj::getsegment(name, NULL, SHT_PROGBITS, SHF_ALLOC, align * 4);
+#elif MACHOBJ
+    return MachObj::getsegment(name, "__DWARF", align * 2, S_ATTR_DEBUG);
+#else
+    assert(0);
+    return 0;
+#endif
+}
+
 // machobj.c
 #define RELaddr 0       // straight address
 #define RELrel  1       // relative to location to be fixed up
@@ -626,13 +638,14 @@ static void writeEhFrameHeader(IDXSEC dfseg, Outbuffer *buf, Symbol *personality
         buf->writeByten(DW_EH_PE_pcrel | DW_EH_PE_sdata4);   // R: encoding of addresses in FDE
     }
 
+    // Set CFA beginning state at function entry point
     if (I64)
     {
-        buf->writeByten(DW_CFA_def_cfa);        // DEF_CFA r7,8
+        buf->writeByten(DW_CFA_def_cfa);        // DEF_CFA r7,8   RSP is at offset 8
         buf->writeByten(7);
         buf->writeByten(8);
 
-        buf->writeByten(DW_CFA_offset + 16);    // OFFSET r16,1
+        buf->writeByten(DW_CFA_offset + 16);    // OFFSET r16,1   RIP is at -8*1[RSP]
         buf->writeByten(1);
     }
     else
@@ -757,17 +770,23 @@ void writeEhFrameFDE(IDXSEC dfseg, Symbol *sfunc)
     const unsigned pad = -fdelen & (I64 ? 7 : 3);      // pad to addressing unit size boundary
     const unsigned length = fdelen + pad - 4;
 
+    buf->reserve(length + 4);
     buf->write32(length);                               // Length (no Extended Length)
     buf->write32((startsize + 4) - CIE_offset);         // CIE Pointer
-    ElfObj::reftoident(dfseg, startsize + 8, sfunc, 0, CFpc32 | CFoff); // PC_begin
+#if ELFOBJ
+    buf->write32(0);                                    // address of function
+    ElfObj::addrel(dfseg, startsize + 8, R_X86_64_PC32, MAP_SEG2SYMIDX(sfunc->Sseg), sfunc->Soffset);
+    //ElfObj::reftoident(dfseg, startsize + 8, sfunc, 0, CFpc32 | CFoff); // PC_begin
+#else
+    assert(0);                                          // not supported yet
+#endif
     buf->write32(sfunc->Ssize);                         // PC Range
     if (config.ehmethod == EH_DWARF)
     {
         buf->writeByten(4);                             // Augmentation Data Length
-        int etseg = dwarf_getsegment(except_table_name, 1);
-        Outbuffer *etbuf = SegData[etseg]->SDbuf;
+        int etseg = dwarf_getsegment_alloc(except_table_name, 1);
         buf->write32(0);                                // address of LSDA (".gcc_except_table")
-        dwarf_addrel(dfseg, buf->size() - 4, etseg, etbuf->size());      // and the fixup
+        dwarf_addrel(dfseg, buf->size() - 4, etseg, sfunc->Sfunc->LSDAoffset);      // and the fixup
     }
     else
         buf->writeByten(0);                             // Augmentation Data Length
@@ -784,9 +803,9 @@ void dwarf_initfile(const char *filename)
 {
     if (config.ehmethod == EH_DWARF)
     {
-        dwarf_getsegment(except_table_name, 1);
+        dwarf_getsegment_alloc(except_table_name, 1);
 
-        int seg = dwarf_getsegment(eh_frame_name, 1);
+        int seg = dwarf_getsegment_alloc(eh_frame_name, I64 ? 2 : 1);
         Outbuffer *buf = SegData[seg]->SDbuf;
         buf->reserve(1000);
         writeEhFrameHeader(seg, buf, getRtlsym(RTLSYM_PERSONALITY));
@@ -1269,7 +1288,7 @@ void dwarf_func_term(Symbol *sfunc)
 
     if (config.ehmethod == EH_DWARF)
     {
-        IDXSEC dfseg = dwarf_getsegment(eh_frame_name, 1);
+        IDXSEC dfseg = dwarf_getsegment_alloc(eh_frame_name, I64 ? 2 : 1);
         writeEhFrameFDE(dfseg, sfunc);
     }
     if (!config.fulltypes)
@@ -2690,9 +2709,10 @@ unsigned dwarf_abbrev_code(unsigned char *data, size_t nbytes)
  */
 void dwarf_except_gentables(Funcsym *sfunc, unsigned startoffset, unsigned retoffset)
 {
-    int seg = dwarf_getsegment(except_table_name, 1);
+    int seg = dwarf_getsegment_alloc(except_table_name, 1);
     Outbuffer *buf = SegData[seg]->SDbuf;
     buf->reserve(100);
+    sfunc->Sfunc->LSDAoffset = buf->size();
     genDwarfEh(sfunc, seg, buf, usednteh & EHcleanup, startoffset, retoffset);
 }
 

src/backend/dwarfeh.c

@@ -57,6 +57,7 @@ struct DwEhTable
 
     DwEhTableEntry *index(unsigned i)
     {
+        if (i >= dim) printf("i = %d dim = %d\n", i, dim);
         assert(i < dim);
         return ptr + i;
     }
@@ -70,7 +71,7 @@ struct DwEhTable
             ptr = (DwEhTableEntry *)::realloc(ptr, capacity * sizeof(DwEhTableEntry));
             assert(ptr);
         }
-        memset(ptr + dim, 0, sizeof(DwEhTable));
+        memset(ptr + dim, 0, sizeof(DwEhTableEntry));
         return dim++;
     }
 };
@@ -114,12 +115,19 @@ void genDwarfEh(Funcsym *sfunc, int seg, Outbuffer *et, bool scancode, unsigned
     et->reserve(100);
     block *startblock = sfunc->Sfunc->Fstartblock;
     //printf("genDwarfEh: func = %s, offset = x%x, startblock->Boffset = x%x, scancode = %d\n",
-    //  sfunc->Sident, (int)sfunc->Soffset, (int)startblock->Boffset, scancode);
+      //sfunc->Sident, (int)sfunc->Soffset, (int)startblock->Boffset, scancode);
+
+#if 0
+    printf("------- before ----------\n");
+    for (block *b = startblock; b; b = b->Bnext) WRblock(b);
+    printf("-------------------------\n");
+#endif
 
     unsigned startsize = et->size();
     assert((startsize & 3) == 0);       // should be aligned
 
     DwEhTable *deh = &dwehtable;
+    deh->dim = 0;
     Outbuffer atbuf;
     Outbuffer cstbuf;
 
@@ -153,9 +161,9 @@ void genDwarfEh(Funcsym *sfunc, int seg, Outbuffer *et, bool scancode, unsigned
             d->start = b->Boffset;
 
             block *bf = b->nthSucc(1);
-            d->lpad = bf->Boffset;
             if (bf->BC == BCjcatch)
             {
+                d->lpad = bf->Boffset;
                 d->bcatch = bf;
                 unsigned *pat = bf->BS.BIJCATCH.actionTable;
                 unsigned length = pat[0];
@@ -170,6 +178,8 @@ void genDwarfEh(Funcsym *sfunc, int seg, Outbuffer *et, bool scancode, unsigned
                 }
                 d->action = offset + 1;
             }
+            else
+                d->lpad = bf->nthSucc(0)->Boffset;
             d->prev = index;
             index = i;
             bprev = b->Btry;
@@ -206,6 +216,30 @@ void genDwarfEh(Funcsym *sfunc, int seg, Outbuffer *et, bool scancode, unsigned
     }
     //printf("deh->dim = %d\n", (int)deh->dim);
 
+#if 1
+    /* Build Call Site Table
+     * Be sure to not generate empty entries,
+     * and generate nested ranges reflecting the layout in the code.
+     */
+    assert(deh->dim);
+    unsigned end = deh->index(0)->start;
+    for (unsigned i = 0; i < deh->dim; ++i)
+    {
+        DwEhTableEntry *d = deh->index(i);
+        if (d->start < d->end)
+        {
+            unsigned CallSiteStart = d->start - startblock->Boffset;
+            cstbuf.writeuLEB128(CallSiteStart);
+            unsigned CallSiteRange = d->end - d->start;
+            cstbuf.writeuLEB128(CallSiteRange);
+            unsigned LandingPad = d->lpad - startblock->Boffset;
+            cstbuf.writeuLEB128(LandingPad);
+            unsigned ActionTable = d->action;
+            cstbuf.writeuLEB128(ActionTable);
+            //printf("\t%x %x %x %x\n", CallSiteStart, CallSiteRange, LandingPad, ActionTable);
+        }
+    }
+#else
     /* Build Call Site Table
      * Be sure to not generate empty entries,
      * and generate multiple entries for one DwEhTableEntry if the latter
@@ -250,6 +284,7 @@ void genDwarfEh(Funcsym *sfunc, int seg, Outbuffer *et, bool scancode, unsigned
             }
         } while (j--);
     }
+#endif
 
     /* Write LSDT header */
     const unsigned char LPstart = DW_EH_PE_omit;

src/backend/rtlsym.h

@@ -144,6 +144,7 @@ SYMBOL_MARS(D_LOCAL_UNWIND2, FLfunc,FREGSAVED,"_d_local_unwind2", 0, tsclib) \
 SYMBOL_SCPP(LOCAL_UNWIND2, FLfunc,FREGSAVED,"_local_unwind2", 0, tsclib) \
 SYMBOL_Z(UNWIND_RESUME, FLfunc,FREGSAVED,"_Unwind_Resume", SFLexit, tsclib) \
 SYMBOL_Z(PERSONALITY, FLfunc,FREGSAVED,"__dmd_personality_v0", 0, tsclib) \
+SYMBOL_Z(BEGIN_CATCH, FLfunc,FREGSAVED,"__dmd_begin_catch", 0, tsclib) \
 \
 SYMBOL_Z(TLS_INDEX, FLextern,0,"_tls_index",0,tsint) \
 SYMBOL_Z(TLS_ARRAY, FLextern,0,"_tls_array",0,tspvoid) \

src/s2ir.c

@@ -971,7 +971,8 @@ class S2irVisitor : public Visitor
 
         incUsage(irs, s->loc);
         elem *e = toElemDtor(s->exp, irs);
-        e = el_bin(OPcall, TYvoid, el_var(getRtlsym(RTLSYM_THROWC)),e);
+        const int rtlthrow = config.ehmethod == EH_DWARF ? RTLSYM_THROWDWARF : RTLSYM_THROWC;
+        e = el_bin(OPcall, TYvoid, el_var(getRtlsym(rtlthrow)),e);
         block_appendexp(blx->curblock, e);
     }
 
@@ -1033,7 +1034,8 @@ class S2irVisitor : public Visitor
              * BCjcatch:
              *  __hander = __RDX;
              *  __exception_object = __RAX;
-             *  jcatchvar = *(__exception_object - Target::ptrsize)
+             *  jcatchvar = *(__exception_object - Target::ptrsize); // old way
+             *  jcatchvar = __dmd_catch_begin(__exception_object);   // new way
              *  switch (__handler)
              *      case 1:     // first catch handler
              *          *(sclosure + cs.var.offset) = cs.var;
@@ -1058,12 +1060,18 @@ class S2irVisitor : public Visitor
             elem *e1 = el_bin(OPeq, TYvoid, el_var(shandler), el_var(sedx)); // __handler = __RDX
             elem *e2 = el_bin(OPeq, TYvoid, el_var(seo), el_var(seax)); // __exception_object = __RAX
 
+#if 0
             // jcatchvar = *(__exception_object - Target::ptrsize)
             union eve c;
             memset(&c, 0, sizeof(c));
             c.Vllong = Target::ptrsize;
-            elem *e = el_bin(OPmin, TYptr, el_var(seo), el_const(TYsize_t, &c));
+            elem *e = el_bin(OPmin, TYnptr, el_var(seo), el_const(TYsize_t, &c));
             elem *e3 = el_bin(OPeq, TYvoid, el_var(tryblock->jcatchvar), el_una(OPind, TYnptr, e));
+#else
+            //  jcatchvar = __dmd_catch_begin(__exception_object);
+            elem *e = el_bin(OPcall, TYnptr, el_var(getRtlsym(RTLSYM_BEGIN_CATCH)), el_var(seo));
+            elem *e3 = el_bin(OPeq, TYvoid, el_var(tryblock->jcatchvar), e);
+#endif
 
             block *bcatch = blx->curblock;
             tryblock->appendSucc(bcatch);
@@ -1572,6 +1580,7 @@ void insertFinallyBlockCalls(block *startblock)
                     eeq->ET = e->ET;
                     eeq->E1->ET = e->ET;
                 }
+                b->Belem = eeq;
 
                 goto case_goto;
             }