diff options
| author | Aleksandar Markovic <amarkovic@wavecomp.com> | 2018-12-25 15:55:09 +0100 |
|---|---|---|
| committer | Aleksandar Markovic <amarkovic@wavecomp.com> | 2019-01-03 17:52:52 +0100 |
| commit | afd47cef11f84b070d760f2270c291df6e762151 (patch) | |
| tree | 2f0e628b40d3325f7122725a0c2d9fa802dde37e /disas/nanomips.cpp | |
| parent | 9980a2251338922e53911a0fded21147b9ca0175 (diff) | |
disas: nanoMIPS: Comment the decoder of 'gpr4.zero' gpr encoding type
Comment the decoder of 'gpr4.zero' gpr encoding type in nanoMIPS
disassembler.
Reviewed-by: Aleksandar Rikalo <arikalo@wavecomp.com>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Diffstat (limited to 'disas/nanomips.cpp')
| -rw-r--r-- | disas/nanomips.cpp | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/disas/nanomips.cpp b/disas/nanomips.cpp index 66b1223f48..de96125186 100644 --- a/disas/nanomips.cpp +++ b/disas/nanomips.cpp @@ -397,6 +397,33 @@ uint64 NMD::encode_rd1_from_rd(uint64 d) } +/* + * NMD::decode_gpr_gpr4_zero() - decoder for 'gpr4.zero' gpr encoding type + * + * Map a 4-bit code to the 5-bit register space according to this pattern: + * + * 1 0 + * 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * | | | | | | | | | | | | | | | | + * | | | | | | | | | | | | └---------------------┐ + * | | | | | | | | | | | └---------------┐ | + * | | | | | | | | | | └---------------┐ | | + * | | | | | | | | | └---------------┐ | | | + * | | | | | | | | └---------------┐ | | | | + * | | | | | | | | | | | | | | | | + * | | | | | | | | | | | | | | | | + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * 3 2 1 0 + * + * This pattern is the same one used for 'gpr4' gpr encoding type, except for + * the input value 3, that is mapped to the output value 0 instead of 11. + * + * Used in handling following instructions: + * + * - MOVE.BALC + * - MOVEP + * - SW[4X4] + */ uint64 NMD::decode_gpr_gpr4_zero(uint64 d) { static uint64 register_list[] = { 8, 9, 10, 0, 4, 5, 6, 7, |