add thread_bss support (#21848)

Author: WalterBright

compiler/src/dmd/backend/debugprint.d

@@ -150,6 +150,10 @@ const(char)* tym_str(tym_t ty)
         strcat(p, "mTYxmmgpr|");
     if (ty & mTYgprxmm)
         strcat(p, "mTYgprxmm|");
+    if (ty & mTYthread)
+        strcat(p, "mTYthread|");
+    if (ty & mTYthreadData)
+        strcat(p, "mTYthreadData|");
     const tyb = tybasic(ty);
     if (tyb >= TYMAX)
     {

compiler/src/dmd/backend/dout.d

@@ -80,7 +80,7 @@ void outdata(Symbol* s)
     debug
     debugy && printf("outdata('%s')\n",s.Sident.ptr);
 
-    //printf("outdata('%s', ty=x%x)\n",s.Sident.ptr,s.Stype.Tty);
+    //printf("outdata('%s', ty=%s)\n",s.Sident.ptr,tym_str(s.Stype.Tty));
     //symbol_print(*s);
 
     // Data segment variables are always live on exit from a function
@@ -152,6 +152,25 @@ void outdata(Symbol* s)
                             assert(config.objfmt == OBJ_MACH && I64);
                             goto case;
                         case mTYthread:
+                        if (config.objfmt == OBJ_MACH && config.target_cpu == TARGET_AArch64)
+                        {
+                            // Special handling
+                            import dmd.backend.machobj : MachObj_thread_vars;
+                            targ_size_t offseti;
+                            int segi = MachObj_thread_vars(*s, offseti, true);
+                            seg_data* pseg = objmod.tlsseg_bss();
+                            s.Sseg = pseg.SDseg;
+                            objmod.data_start(s, datasize, pseg.SDseg);
+                            objmod.lidata(pseg.SDseg, pseg.SDoffset, datasize); // I think this section is readonly, so data should overlap
+                                                                                // instead of being consecutive as gcc emits it
+                            s.Sfl = FL.tlsdata;
+
+                            //              if (s.Sclass == SC.global || s.Sclass == SC.static_)
+                            //                  objmod.pubdefsize(seg,s,s.Soffset,datasize);    // do the definition
+
+                            // BUG AArch64: symbolic debug info?
+                            break;
+                        }
                         {   seg_data* pseg = objmod.tlsseg_bss();
                             s.Sseg = pseg.SDseg;
                             objmod.data_start(s, datasize, pseg.SDseg);
@@ -273,7 +292,7 @@ void outdata(Symbol* s)
                 // Special handling
                 import dmd.backend.machobj : MachObj_thread_vars;
                 targ_size_t offseti;
-                int segi = MachObj_thread_vars(*s, offseti);
+                int segi = MachObj_thread_vars(*s, offseti, false);
                 dt_writeToObj(objmod, dtstart, segi, offseti);
                 Offset(segi) = offseti;
                 dt_free(dtstart);

compiler/src/dmd/backend/machobj.d

@@ -1091,9 +1091,9 @@ void MachObj_term(const(char)[] objfilename)
                             fobjbuf.write(&rel, rel.sizeof);
                             foffset += rel.sizeof;
                             nreloc++;
-                            int32_t* p = patchAddr64(seg, r.offset);
+                            //int32_t* p = patchAddr64(seg, r.offset);
                             // Absolute address; add in addr of start of targ seg
-                            *p += SecHdrTab64[SegData[s.Sseg].SDshtidx].addr + s.Soffset;
+                            //  *p += SecHdrTab64[SegData[s.Sseg].SDshtidx].addr + s.Soffset;
                             //patch(pseg, r.offset, s.Sseg, s.Soffset);
                         }
                         else if (s.Sclass == SC.extern_ ||
@@ -1994,14 +1994,18 @@ seg_data* MachObj_tlsseg()
 
 /*******************************************
  * Emit 24 byte __thread_vars section for AArch64.
+ * Params:
+ *      s = Symbol for variable to be added to __thread_vars section
+ *      offset = set to offset to start of where to write initializer data
+ *      bss = true to write to __thread_bss, false to __thread_data
  * Returns:
  *      segment to write initialization data to
  */
 @trusted
-int MachObj_thread_vars(ref Symbol s, out targ_size_t offset)
+int MachObj_thread_vars(ref Symbol s, out targ_size_t offset, bool bss)
 {
-    printf("MachObj_thread_vars(s)\n");
-    symbol_print(s);
+    //printf("MachObj_thread_vars(s)\n");
+    //symbol_print(s);
     /* create _ident$tlv$init Symbol si
      */
     Symbol* si;
@@ -2020,12 +2024,21 @@ int MachObj_thread_vars(ref Symbol s, out targ_size_t offset)
             mem_free(dest.ptr);
     }
 
-    /* write _ident$tlv$init to __thread_data section
+    /* write _ident$tlv$init to __thread_bss / __thread_data section
      */
-    MachObj_tlsseg_data();
-    si.Sseg = seg_tlsseg_data;
+    if (bss)
+    {
+        MachObj_tlsseg_bss();
+        si.Sseg = seg_tlsseg_bss;
+        offset = 0;
+    }
+    else
+    {
+        MachObj_tlsseg_data();
+        si.Sseg = seg_tlsseg_data;
+        offset = SegData[si.Sseg].SDbuf.length();
+    }
     si.Sfl = FL.tlsdata;
-    offset = SegData[si.Sseg].SDbuf.length();
     MachObj_pubdef(si.Sseg, si, offset);
 
     /* Create __thread_vars section, and s will refer to it