+/* Examine the instruction pointed to by PC. If it corresponds to
+ a call to __main, return the address of the next instruction.
+ Otherwise, return PC. */
+
+static CORE_ADDR
+frv_skip_main_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ gdb_byte buf[4];
+ unsigned long op;
+ CORE_ADDR orig_pc = pc;
+
+ if (target_read_memory (pc, buf, 4))
+ return pc;
+ op = extract_unsigned_integer (buf, 4, byte_order);
+
+ /* In PIC code, GR15 may be loaded from some offset off of FP prior
+ to the call instruction.
+
+ Skip over this instruction if present. It won't be present in
+ non-PIC code, and even in PIC code, it might not be present.
+ (This is due to the fact that GR15, the FDPIC register, already
+ contains the correct value.)
+
+ The general form of the LDI is given first, followed by the
+ specific instruction with the GRi and GRk filled in as FP and
+ GR15.
+
+ ldi @(GRi, d12), GRk
+ P KKKKKK 0110010 IIIIII SSSSSSSSSSSS = 0x00c80000
+ 0 000000 1111111 000000 000000000000 = 0x01fc0000
+ . . . . . . . .
+ ldi @(FP, d12), GR15
+ P KKKKKK 0110010 IIIIII SSSSSSSSSSSS = 0x1ec82000
+ 0 001111 1111111 000010 000000000000 = 0x7ffff000
+ . . . . . . . . */
+
+ if ((op & 0x7ffff000) == 0x1ec82000)
+ {
+ pc += 4;
+ if (target_read_memory (pc, buf, 4))
+ return orig_pc;
+ op = extract_unsigned_integer (buf, 4, byte_order);
+ }
+
+ /* The format of an FRV CALL instruction is as follows:
+
+ call label24
+ P HHHHHH 0001111 LLLLLLLLLLLLLLLLLL = 0x003c0000
+ 0 000000 1111111 000000000000000000 = 0x01fc0000
+ . . . . . . . .
+
+ where label24 is constructed by concatenating the H bits with the
+ L bits. The call target is PC + (4 * sign_ext(label24)). */
+
+ if ((op & 0x01fc0000) == 0x003c0000)
+ {
+ LONGEST displ;
+ CORE_ADDR call_dest;
+ struct bound_minimal_symbol s;
+
+ displ = ((op & 0xfe000000) >> 7) | (op & 0x0003ffff);
+ if ((displ & 0x00800000) != 0)
+ displ |= ~((LONGEST) 0x00ffffff);
+
+ call_dest = pc + 4 * displ;
+ s = lookup_minimal_symbol_by_pc (call_dest);
+
+ if (s.minsym != NULL
+ && MSYMBOL_LINKAGE_NAME (s.minsym) != NULL
+ && strcmp (MSYMBOL_LINKAGE_NAME (s.minsym), "__main") == 0)
+ {
+ pc += 4;
+ return pc;
+ }
+ }
+ return orig_pc;
+}
+
+