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authorNick Clifton <nickc@redhat.com>2000-11-30 01:55:12 +0000
committerNick Clifton <nickc@redhat.com>2000-11-30 01:55:12 +0000
commit99901033941c5df3b5a97ef76d1a35bbc3e5313c (patch)
treead56d39c6970c9e6b6dc1e9799816d69a0fba63b /sim/arm/thumbemu.c
parent9d105ab744f1aa43e84b88f820ac2047d4bd55b2 (diff)
downloadgdb-99901033941c5df3b5a97ef76d1a35bbc3e5313c.tar.gz
Add support for ARM's v5TE architecture and Intel's XScale extenstions
Diffstat (limited to 'sim/arm/thumbemu.c')
-rw-r--r--sim/arm/thumbemu.c101
1 files changed, 81 insertions, 20 deletions
diff --git a/sim/arm/thumbemu.c b/sim/arm/thumbemu.c
index dc90dd7cf48..3351c2f65da 100644
--- a/sim/arm/thumbemu.c
+++ b/sim/arm/thumbemu.c
@@ -209,11 +209,19 @@ tdstate ARMul_ThumbDecode (state, pc, tinstr, ainstr)
*ainstr = 0xE12FFF10 /* base */
| ((tinstr & 0x0078) >> 3); /* Rd */
break;
+ case 0xE: /* UNDEFINED */
+ case 0xF: /* UNDEFINED */
+ if (state->is_v5)
+ {
+ /* BLX Rs; BLX Hs */
+ *ainstr = 0xE12FFF30 /* base */
+ | ((tinstr & 0x0078) >> 3); /* Rd */
+ break;
+ }
+ /* Drop through. */
case 0x0: /* UNDEFINED */
case 0x4: /* UNDEFINED */
case 0x8: /* UNDEFINED */
- case 0xE: /* UNDEFINED */
- case 0xF: /* UNDEFINED */
valid = t_undefined;
break;
}
@@ -322,30 +330,48 @@ tdstate ARMul_ThumbDecode (state, pc, tinstr, ainstr)
break;
case 22:
case 23:
- if ((tinstr & 0x0F00) == 0x0000)
+ switch (tinstr & 0x0F00)
{
+ case 0x0000:
/* Format 13 */
/* NOTE: The instruction contains a shift left of 2
- equivalent (implemented as ROR #30): */
+ equivalent (implemented as ROR #30): */
*ainstr = ((tinstr & (1 << 7)) /* base */
? 0xE24DDF00 /* SUB */
: 0xE28DDF00) /* ADD */
| (tinstr & 0x007F); /* off7 */
- }
- else if ((tinstr & 0x0F00) == 0x0e00)
- *ainstr = 0xEF000000 | SWI_Breakpoint;
- else
- {
- /* Format 14 */
- ARMword subset[4] = {
- 0xE92D0000, /* STMDB sp!,{rlist} */
- 0xE92D4000, /* STMDB sp!,{rlist,lr} */
- 0xE8BD0000, /* LDMIA sp!,{rlist} */
- 0xE8BD8000 /* LDMIA sp!,{rlist,pc} */
- };
- *ainstr = subset[((tinstr & (1 << 11)) >> 10)
- | ((tinstr & (1 << 8)) >> 8)] /* base */
- | (tinstr & 0x00FF); /* mask8 */
+ break;
+ case 0x0400:
+ /* Format 14 - Push */
+ * ainstr = 0xE92D0000 | (tinstr & 0x00FF);
+ break;
+ case 0x0500:
+ /* Format 14 - Push + LR */
+ * ainstr = 0xE92D4000 | (tinstr & 0x00FF);
+ break;
+ case 0x0c00:
+ /* Format 14 - Pop */
+ * ainstr = 0xE8BD0000 | (tinstr & 0x00FF);
+ break;
+ case 0x0d00:
+ /* Format 14 - Pop + PC */
+ * ainstr = 0xE8BD8000 | (tinstr & 0x00FF);
+ break;
+ case 0x0e00:
+ if (state->is_v5)
+ {
+ /* This is normally an undefined instruction. The v5t architecture
+ defines this particular pattern as a BKPT instruction, for
+ hardware assisted debugging. We map onto the arm BKPT
+ instruction. */
+ * ainstr = 0xE1200070 | ((tinstr & 0xf0) << 4) | (tinstr & 0xf);
+ break;
+ }
+ /* Drop through. */
+ default:
+ /* Everything else is an undefined instruction. */
+ valid = t_undefined;
+ break;
}
break;
case 24: /* STMIA */
@@ -446,6 +472,34 @@ tdstate ARMul_ThumbDecode (state, pc, tinstr, ainstr)
valid = t_branch;
break;
case 29: /* UNDEFINED */
+ if (state->is_v5)
+ {
+ if (tinstr & 1)
+ {
+ valid = t_undefined;
+ break;
+ }
+ /* Drop through. */
+
+ do_blx2: /* BLX instruction 2 */
+ /* Format 19 */
+ /* There is no single ARM instruction equivalent for this
+ instruction. Also, it should only ever be matched with the
+ fmt19 "BL/BLX instruction 1" instruction. However, we do
+ allow the simulation of it on its own, with undefined results
+ if r14 is not suitably initialised. */
+ {
+ ARMword tmp = (pc + 2);
+
+ state->Reg[15] = ((state->Reg[14] + ((tinstr & 0x07FF) << 1))
+ & 0xFFFFFFFC);
+ CLEART;
+ state->Reg[14] = (tmp | 1);
+ valid = t_branch;
+ FLUSHPIPE;
+ break;
+ }
+ }
valid = t_undefined;
break;
case 30: /* BL instruction 1 */
@@ -461,7 +515,14 @@ tdstate ARMul_ThumbDecode (state, pc, tinstr, ainstr)
valid = t_branch; /* in-case we don't have the 2nd half */
tinstr = next_instr; /* move the instruction down */
if (((tinstr & 0xF800) >> 11) != 31)
- break; /* exit, since not correct instruction */
+ {
+ if (((tinstr & 0xF800) >> 11) == 29)
+ {
+ pc += 2;
+ goto do_blx2;
+ }
+ break; /* exit, since not correct instruction */
+ }
/* else we fall through to process the second half of the BL */
pc += 2; /* point the pc at the 2nd half */
case 31: /* BL instruction 2 */