[patch, moxie] simulator updates

[Anthony Green <green at moxielogic dot com>]

I've committed the following patch for the moxie simulator. 

It increases the default simulated memory size, supports the new moxie
system call ABI from libgloss and implements proper exception processing
for Linux system call support.


2009-07-31  Anthony Green  <green@moxielogic.com>

	* interp.c: Increase simulated memory to 16MB.
	(sim_resume): Tweak swi system calls to support new ABI (up to 5
	args in regs).  Also simluate proper exception processing for
	Linux system calls.



Index: sim/moxie/interp.c
===================================================================
RCS file: /cvs/src/src/sim/moxie/interp.c,v
retrieving revision 1.3
diff -u -r1.3 interp.c
--- sim/moxie/interp.c	11 Jun 2009 11:36:14 -0000	1.3
+++ sim/moxie/interp.c	31 Jul 2009 11:38:28 -0000
@@ -132,8 +132,8 @@
 static SIM_OPEN_KIND sim_kind;
 static int issue_messages = 0;
 
-/* Default to a 8 Mbyte (== 2^23) memory space.  */
-static int sim_memory_size = 23;
+/* Default to a 16 Mbyte (== 2^23) memory space.  */
+static int sim_memory_size = 24;
 
 #define	MEM_SIZE_FLOOR	64
 void
@@ -997,12 +997,8 @@
 		    {
 		      char *fname = &memory[cpu.asregs.regs[2]];
 		      int mode = (int) convert_target_flags ((unsigned) cpu.asregs.regs[3]);
-		      /* Permission bits are at 0x12($fp) */
-		      int perm = (int) EXTRACT_WORD(&memory[cpu.asregs.regs[0] + 20]);
+		      int perm = (int) cpu.asregs.regs[4];
 		      int fd = open (fname, mode, perm);
-#if 0
-		      fprintf(stderr, "open(\"%s\", 0x%x, 0x%x) = %d\n", fname, mode, perm, fd);
-#endif
 		      /* FIXME - set errno */
 		      cpu.asregs.regs[2] = fd;
 		      break;
@@ -1011,8 +1007,7 @@
 		    {
 		      int fd = cpu.asregs.regs[2];
 		      char *buf = &memory[cpu.asregs.regs[3]];
-		      /* String length is at 0x12($fp) */
-		      unsigned len = EXTRACT_WORD(&memory[cpu.asregs.regs[0] + 20]);
+		      unsigned len = (unsigned) cpu.asregs.regs[4];
 		      cpu.asregs.regs[2] = read (fd, buf, len);
 		      break;
 		    }
@@ -1020,11 +1015,33 @@
 		    {
 		      char *str = &memory[cpu.asregs.regs[3]];
 		      /* String length is at 0x12($fp) */
-		      unsigned count, len = EXTRACT_WORD(&memory[cpu.asregs.regs[0] + 20]);
+		      unsigned count, len = (unsigned) cpu.asregs.regs[4];
 		      count = write (cpu.asregs.regs[2], str, len);
 		      cpu.asregs.regs[2] = count;
 		      break;
 		    }
+		  case 0xffffffff: /* Linux System Call */
+		    {
+		      unsigned int handler = cpu.asregs.sregs[1];
+		      unsigned int sp = cpu.asregs.regs[1];
+		      cpu.asregs.sregs[2] = 3; /* MOXIE_EX_SWI */
+
+		      /* Save a slot for the static chain.  */
+		      sp -= 4;
+
+		      /* Push the return address.  */
+		      sp -= 4;
+		      wlat (opc, sp, pc + 6);
+		
+		      /* Push the current frame pointer.  */
+		      sp -= 4;
+		      wlat (opc, sp, cpu.asregs.regs[0]);
+
+		      /* Uncache the stack pointer and set the fp & pc.  */
+		      cpu.asregs.regs[1] = sp;
+		      cpu.asregs.regs[0] = sp;
+		      pc = handler - 6;
+		    }
 		  default:
 		    break;
 		  }