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| author | Aurelien Jarno <aurelien@aurel32.net> | 2013-09-03 08:27:39 +0200 |
|---|---|---|
| committer | Richard Henderson <rth@twiddle.net> | 2014-02-17 10:12:28 -0600 |
| commit | c8d70272535b84ccd3cd1a3dcad65aed34be6bb4 (patch) | |
| tree | 22af40921850606d9ead33987d649e46102f897c /tcg | |
| parent | f096dc96188378bc2bcd80683490ca386b0c1683 (diff) | |
| download | qemu-c8d70272535b84ccd3cd1a3dcad65aed34be6bb4.tar.gz | |
tcg/optimize: add known-zero bits compute for load ops
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'tcg')
| -rw-r--r-- | tcg/optimize.c | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/tcg/optimize.c b/tcg/optimize.c index 1cf017aab8..1b9fea5a3d 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -779,13 +779,37 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, mask = temps[args[3]].mask | temps[args[4]].mask; break; + CASE_OP_32_64(ld8u): + case INDEX_op_qemu_ld8u: + mask = 0xff; + break; + CASE_OP_32_64(ld16u): + case INDEX_op_qemu_ld16u: + mask = 0xffff; + break; + case INDEX_op_ld32u_i64: +#if TCG_TARGET_REG_BITS == 64 + case INDEX_op_qemu_ld32u: +#endif + mask = 0xffffffffu; + break; + + CASE_OP_32_64(qemu_ld): + { + TCGMemOp mop = args[def->nb_oargs + def->nb_iargs]; + if (!(mop & MO_SIGN)) { + mask = (2ULL << ((8 << (mop & MO_SIZE)) - 1)) - 1; + } + } + break; + default: break; } /* 32-bit ops (non 64-bit ops and non load/store ops) generate 32-bit results */ - if (!(tcg_op_defs[op].flags & (TCG_OPF_CALL_CLOBBER | TCG_OPF_64BIT))) { + if (!(def->flags & (TCG_OPF_CALL_CLOBBER | TCG_OPF_64BIT))) { mask &= 0xffffffffu; } |