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authorNathan Froyd <froydnj@codesourcery.com>2010-06-08 13:29:58 -0700
committerAurelien Jarno <aurelien@aurel32.net>2010-06-09 16:10:50 +0200
commit620e48f66350991918dd78e9a686a9b159fec111 (patch)
treef02400793e4de3552320382d8fa90229115a9f9b /target-mips
parent8153667c718e359368f306e1b2c144596dec5f80 (diff)
target-mips: mips16 cleanups
Change code handling mips16-specific branches to use ISA-neutral special opcodes. Since there are several places where the delay slot requirements for microMIPS branches differ from mips16 branches, using opcodes is easier than checking hflags, then checking mips16 vs. microMIPS. Signed-off-by: Nathan Froyd <froydnj@codesourcery.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Diffstat (limited to 'target-mips')
-rw-r--r--target-mips/translate.c24
1 files changed, 17 insertions, 7 deletions
diff --git a/target-mips/translate.c b/target-mips/translate.c
index c3182c5250..78783a8d51 100644
--- a/target-mips/translate.c
+++ b/target-mips/translate.c
@@ -68,6 +68,7 @@ enum {
/* Jump and branches */
OPC_J = (0x02 << 26),
OPC_JAL = (0x03 << 26),
+ OPC_JALS = OPC_JAL | 0x5,
OPC_BEQ = (0x04 << 26), /* Unconditional if rs = rt = 0 (B) */
OPC_BEQL = (0x14 << 26),
OPC_BNE = (0x05 << 26),
@@ -77,6 +78,7 @@ enum {
OPC_BGTZ = (0x07 << 26),
OPC_BGTZL = (0x17 << 26),
OPC_JALX = (0x1D << 26), /* MIPS 16 only */
+ OPC_JALXS = OPC_JALX | 0x5,
/* Load and stores */
OPC_LDL = (0x1A << 26),
OPC_LDR = (0x1B << 26),
@@ -177,6 +179,7 @@ enum {
OPC_JR = 0x08 | OPC_SPECIAL, /* Also JR.HB */
OPC_JALR = 0x09 | OPC_SPECIAL, /* Also JALR.HB */
OPC_JALRC = OPC_JALR | (0x5 << 6),
+ OPC_JALRS = 0x10 | OPC_SPECIAL | (0x5 << 6),
/* Traps */
OPC_TGE = 0x30 | OPC_SPECIAL,
OPC_TGEU = 0x31 | OPC_SPECIAL,
@@ -2466,12 +2469,15 @@ static void gen_compute_branch (DisasContext *ctx, uint32_t opc,
case OPC_J:
case OPC_JAL:
case OPC_JALX:
+ case OPC_JALS:
+ case OPC_JALXS:
/* Jump to immediate */
btgt = ((ctx->pc + insn_bytes) & (int32_t)0xF0000000) | (uint32_t)offset;
break;
case OPC_JR:
case OPC_JALR:
case OPC_JALRC:
+ case OPC_JALRS:
/* Jump to register */
if (offset != 0 && offset != 16) {
/* Hint = 0 is JR/JALR, hint 16 is JR.HB/JALR.HB, the
@@ -2534,29 +2540,33 @@ static void gen_compute_branch (DisasContext *ctx, uint32_t opc,
ctx->hflags |= MIPS_HFLAG_B;
MIPS_DEBUG("j " TARGET_FMT_lx, btgt);
break;
+ case OPC_JALXS:
case OPC_JALX:
ctx->hflags |= MIPS_HFLAG_BX;
/* Fallthrough */
+ case OPC_JALS:
case OPC_JAL:
blink = 31;
ctx->hflags |= MIPS_HFLAG_B;
- ctx->hflags |= (ctx->hflags & MIPS_HFLAG_M16
+ ctx->hflags |= ((opc == OPC_JALS || opc == OPC_JALXS)
? MIPS_HFLAG_BDS16
: MIPS_HFLAG_BDS32);
MIPS_DEBUG("jal " TARGET_FMT_lx, btgt);
break;
case OPC_JR:
ctx->hflags |= MIPS_HFLAG_BR;
- if (ctx->hflags & MIPS_HFLAG_M16)
- ctx->hflags |= MIPS_HFLAG_BDS16;
+ if (insn_bytes == 4)
+ ctx->hflags |= MIPS_HFLAG_BDS32;
MIPS_DEBUG("jr %s", regnames[rs]);
break;
+ case OPC_JALRS:
case OPC_JALR:
case OPC_JALRC:
blink = rt;
ctx->hflags |= MIPS_HFLAG_BR;
- if (ctx->hflags & MIPS_HFLAG_M16)
- ctx->hflags |= MIPS_HFLAG_BDS16;
+ ctx->hflags |= (opc == OPC_JALRS
+ ? MIPS_HFLAG_BDS16
+ : MIPS_HFLAG_BDS32);
MIPS_DEBUG("jalr %s, %s", regnames[rt], regnames[rs]);
break;
default:
@@ -8487,7 +8497,7 @@ static int decode_mips16_opc (CPUState *env, DisasContext *ctx,
offset = (((ctx->opcode & 0x1f) << 21)
| ((ctx->opcode >> 5) & 0x1f) << 16
| offset) << 2;
- op = ((ctx->opcode >> 10) & 0x1) ? OPC_JALX : OPC_JAL;
+ op = ((ctx->opcode >> 10) & 0x1) ? OPC_JALXS : OPC_JALS;
gen_compute_branch(ctx, op, 4, rx, ry, offset);
n_bytes = 4;
*is_branch = 1;
@@ -8726,7 +8736,7 @@ static int decode_mips16_opc (CPUState *env, DisasContext *ctx,
int ra = (ctx->opcode >> 5) & 0x1;
if (link) {
- op = nd ? OPC_JALRC : OPC_JALR;
+ op = nd ? OPC_JALRC : OPC_JALRS;
} else {
op = OPC_JR;
}