Remove unused runtime symbols (#21629)

Author: Albert24GG

compiler/src/dmd/backend/drtlsym.d

@@ -103,12 +103,10 @@ Symbol* getRtlsym(RTLSYM i) @trusted
         case RTLSYM.MEMSETDOUBLE:           symbolz(ps,FL.func,FREGSAVED,"_memsetDouble", 0, t); break;
         case RTLSYM.MEMSETSIMD:             symbolz(ps,FL.func,FREGSAVED,"_memsetSIMD",0, t); break;
         case RTLSYM.MEMSETN:                symbolz(ps,FL.func,FREGSAVED,"_memsetn",  0, t); break;
-        case RTLSYM.NEWTHROW:               symbolz(ps,FL.func,FREGSAVED,"_d_newThrowable", 0, t); break;
         case RTLSYM.ASSOCARRAYLITERALTX:    symbolz(ps,FL.func,FREGSAVED,"_d_assocarrayliteralTX", 0, t); break;
         case RTLSYM.CALLFINALIZER:          symbolz(ps,FL.func,FREGSAVED,"_d_callfinalizer", 0, t); break;
         case RTLSYM.CALLINTERFACEFINALIZER: symbolz(ps,FL.func,FREGSAVED,"_d_callinterfacefinalizer", 0, t); break;
         case RTLSYM.ALLOCMEMORY:            symbolz(ps,FL.func,FREGSAVED,"_d_allocmemory", 0, t); break;
-        case RTLSYM.ARRAYCATT:              symbolz(ps,FL.func,FREGSAVED,"_d_arraycatT", 0, t); break;
         case RTLSYM.ARRAYAPPENDCD:          symbolz(ps,FL.func,FREGSAVED,"_d_arrayappendcd", 0, t); break;
         case RTLSYM.ARRAYAPPENDWD:          symbolz(ps,FL.func,FREGSAVED,"_d_arrayappendwd", 0, t); break;
         case RTLSYM.ARRAYCOPY:              symbolz(ps,FL.func,FREGSAVED,"_d_arraycopy", 0, t); break;

compiler/src/dmd/backend/rtlsym.d

@@ -47,13 +47,11 @@ enum RTLSYM
     MEMSETDOUBLE,
     MEMSETSIMD,
     MEMSETN,
-    NEWTHROW,
 
     ASSOCARRAYLITERALTX,
     CALLFINALIZER,
     CALLINTERFACEFINALIZER,
     ALLOCMEMORY,
-    ARRAYCATT,
     ARRAYAPPENDCD,
     ARRAYAPPENDWD,
     ARRAYCOPY,

compiler/src/dmd/e2ir.d

@@ -367,12 +367,6 @@ void toTraceGC(ref IRState irs, elem* e, Loc loc)
     assert(e1.Eoper == OPvar);
 
     auto s = e1.Vsym;
-    /* In -dip1008 code the allocation of exceptions is no longer done by the
-     * gc, but by a manual reference counting mechanism implementend in druntime.
-     * If that is the case, then there is nothing to trace.
-     */
-    if (s == getRtlsym(RTLSYM.NEWTHROW))
-        return;
     foreach (ref m; map)
     {
         if (s == getRtlsym(m[0]))