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| author | Tom Musta <tommusta@gmail.com> | 2014-04-21 15:55:20 -0500 |
|---|---|---|
| committer | Alexander Graf <agraf@suse.de> | 2014-06-16 13:24:32 +0200 |
| commit | 297666eba0f6d73b5969763aec2b3f8ac4123b9a (patch) | |
| tree | da4d38183e71725408117bdf23573f553fb5d635 /target-ppc/dfp_helper.c | |
| parent | e8a484603146f7e2523749ad06e6ea43b26cf411 (diff) | |
| download | qemu-297666eba0f6d73b5969763aec2b3f8ac4123b9a.tar.gz qemu-297666eba0f6d73b5969763aec2b3f8ac4123b9a.tar.bz2 qemu-297666eba0f6d73b5969763aec2b3f8ac4123b9a.zip | |
target-ppc: Introduce DFP Insert Biased Exponent
Add emulation of the PowerPC Decimal Floating Point Insert Biased
Exponent instructions diex[q][.].
Signed-off-by: Tom Musta <tommusta@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Diffstat (limited to 'target-ppc/dfp_helper.c')
| -rw-r--r-- | target-ppc/dfp_helper.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/target-ppc/dfp_helper.c b/target-ppc/dfp_helper.c index 8c8ee795c7..adb9763192 100644 --- a/target-ppc/dfp_helper.c +++ b/target-ppc/dfp_helper.c @@ -1152,3 +1152,71 @@ void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b) \ DFP_HELPER_XEX(dxex, 64) DFP_HELPER_XEX(dxexq, 128) + +static void dfp_set_raw_exp_64(uint64_t *t, uint64_t raw) +{ + *t &= 0x8003ffffffffffffULL; + *t |= (raw << (63-13)); +} + +static void dfp_set_raw_exp_128(uint64_t *t, uint64_t raw) +{ + t[HI_IDX] &= 0x80003fffffffffffULL; + t[HI_IDX] |= (raw << (63-17)); +} + +#define DFP_HELPER_IEX(op, size) \ +void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *a, uint64_t *b) \ +{ \ + struct PPC_DFP dfp; \ + uint64_t raw_qnan, raw_snan, raw_inf, max_exp; \ + int bias; \ + int64_t exp = *((int64_t *)a); \ + \ + dfp_prepare_decimal##size(&dfp, 0, b, env); \ + \ + if ((size) == 64) { \ + max_exp = 767; \ + raw_qnan = 0x1F00; \ + raw_snan = 0x1F80; \ + raw_inf = 0x1E00; \ + bias = 398; \ + } else if ((size) == 128) { \ + max_exp = 12287; \ + raw_qnan = 0x1f000; \ + raw_snan = 0x1f800; \ + raw_inf = 0x1e000; \ + bias = 6176; \ + } else { \ + assert(0); \ + } \ + \ + if (unlikely((exp < 0) || (exp > max_exp))) { \ + dfp.t64[0] = dfp.b64[0]; \ + dfp.t64[1] = dfp.b64[1]; \ + if (exp == -1) { \ + dfp_set_raw_exp_##size(dfp.t64, raw_inf); \ + } else if (exp == -3) { \ + dfp_set_raw_exp_##size(dfp.t64, raw_snan); \ + } else { \ + dfp_set_raw_exp_##size(dfp.t64, raw_qnan); \ + } \ + } else { \ + dfp.t = dfp.b; \ + if (unlikely(decNumberIsSpecial(&dfp.t))) { \ + dfp.t.bits &= ~DECSPECIAL; \ + } \ + dfp.t.exponent = exp - bias; \ + decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, \ + &dfp.context); \ + } \ + 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_IEX(diex, 64) +DFP_HELPER_IEX(diexq, 128) |