target-ppc: Introduce DFP Encode BCD to DPD

Add emulation of the PowerPC Decimal Floating Point Encode Binary
Coded Decimal to Densely Packed Decimal instructions denbcd[q][.].

Signed-off-by: Tom Musta <tommusta@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
Tom Musta 2014-04-21 15:55:18 -05:00 committed by Alexander Graf
parent 7796676fdd
commit 013c3ac070
3 changed files with 78 additions and 0 deletions

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@ -1049,3 +1049,75 @@ void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b, uint32_t sp) \
DFP_HELPER_DEDPD(ddedpd, 64)
DFP_HELPER_DEDPD(ddedpdq, 128)
static inline uint8_t dfp_get_bcd_digit_64(uint64_t *t, unsigned n)
{
return *t >> ((n << 2) & 63) & 15;
}
static inline uint8_t dfp_get_bcd_digit_128(uint64_t *t, unsigned n)
{
return t[(n & 0x10) ? HI_IDX : LO_IDX] >> ((n << 2) & 63) & 15;
}
#define DFP_HELPER_ENBCD(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b, uint32_t s) \
{ \
struct PPC_DFP dfp; \
uint8_t digits[32]; \
int n = 0, offset = 0, sgn = 0, nonzero = 0; \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
decNumberZero(&dfp.t); \
\
if (s) { \
uint8_t sgnNibble = dfp_get_bcd_digit_##size(dfp.b64, offset++); \
switch (sgnNibble) { \
case 0xD: \
case 0xB: \
sgn = 1; \
break; \
case 0xC: \
case 0xF: \
case 0xA: \
case 0xE: \
sgn = 0; \
break; \
default: \
dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FPSCR_VE); \
return; \
} \
} \
\
while (offset < (size)/4) { \
n++; \
digits[(size)/4-n] = dfp_get_bcd_digit_##size(dfp.b64, offset++); \
if (digits[(size)/4-n] > 10) { \
dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FPSCR_VE); \
return; \
} else { \
nonzero |= (digits[(size)/4-n] > 0); \
} \
} \
\
if (nonzero) { \
decNumberSetBCD(&dfp.t, digits+((size)/4)-n, n); \
} \
\
if (s && sgn) { \
dfp.t.bits |= DECNEG; \
} \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, \
&dfp.context); \
dfp_set_FPRF_from_FRT(&dfp); \
if ((size) == 64) { \
t[0] = dfp.t64[0]; \
} else if ((size) == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
DFP_HELPER_ENBCD(denbcd, 64)
DFP_HELPER_ENBCD(denbcdq, 128)

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@ -656,3 +656,5 @@ DEF_HELPER_3(dctfix, void, env, fprp, fprp)
DEF_HELPER_3(dctfixq, void, env, fprp, fprp)
DEF_HELPER_4(ddedpd, void, env, fprp, fprp, i32)
DEF_HELPER_4(ddedpdq, void, env, fprp, fprp, i32)
DEF_HELPER_4(denbcd, void, env, fprp, fprp, i32)
DEF_HELPER_4(denbcdq, void, env, fprp, fprp, i32)

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@ -8396,6 +8396,8 @@ GEN_DFP_T_B_Rc(dctfix)
GEN_DFP_T_B_Rc(dctfixq)
GEN_DFP_T_FPR_I32_Rc(ddedpd, rB, SP)
GEN_DFP_T_FPR_I32_Rc(ddedpdq, rB, SP)
GEN_DFP_T_FPR_I32_Rc(denbcd, rB, SP)
GEN_DFP_T_FPR_I32_Rc(denbcdq, rB, SP)
/*** SPE extension ***/
/* Register moves */
@ -11363,6 +11365,8 @@ GEN_DFP_T_B_Rc(dctfix, 0x02, 0x09),
GEN_DFP_T_Bp_Rc(dctfixq, 0x02, 0x09),
GEN_DFP_SP_T_B_Rc(ddedpd, 0x02, 0x0a),
GEN_DFP_SP_Tp_Bp_Rc(ddedpdq, 0x02, 0x0a),
GEN_DFP_S_T_B_Rc(denbcd, 0x02, 0x1a),
GEN_DFP_S_Tp_Bp_Rc(denbcdq, 0x02, 0x1a),
#undef GEN_SPE
#define GEN_SPE(name0, name1, opc2, opc3, inval0, inval1, type) \
GEN_OPCODE_DUAL(name0##_##name1, 0x04, opc2, opc3, inval0, inval1, type, PPC_NONE)