diff options
| -rw-r--r-- | tcg/arm/tcg-target.c.inc | 41 |
1 files changed, 21 insertions, 20 deletions
diff --git a/tcg/arm/tcg-target.c.inc b/tcg/arm/tcg-target.c.inc index 4b0b4f4c2f..d290b4556c 100644 --- a/tcg/arm/tcg-target.c.inc +++ b/tcg/arm/tcg-target.c.inc @@ -1396,16 +1396,9 @@ static TCGReg tcg_out_tlb_read(TCGContext *s, TCGReg addrlo, TCGReg addrhi, int cmp_off = (is_load ? offsetof(CPUTLBEntry, addr_read) : offsetof(CPUTLBEntry, addr_write)); int fast_off = TLB_MASK_TABLE_OFS(mem_index); - unsigned s_bits = opc & MO_SIZE; - unsigned a_bits = get_alignment_bits(opc); - - /* - * We don't support inline unaligned acceses, but we can easily - * support overalignment checks. - */ - if (a_bits < s_bits) { - a_bits = s_bits; - } + unsigned s_mask = (1 << (opc & MO_SIZE)) - 1; + unsigned a_mask = (1 << get_alignment_bits(opc)) - 1; + TCGReg t_addr; /* Load env_tlb(env)->f[mmu_idx].{mask,table} into {r0,r1}. */ tcg_out_ldrd_8(s, COND_AL, TCG_REG_R0, TCG_AREG0, fast_off); @@ -1440,27 +1433,35 @@ static TCGReg tcg_out_tlb_read(TCGContext *s, TCGReg addrlo, TCGReg addrhi, /* * Check alignment, check comparators. - * Do this in no more than 3 insns. Use MOVW for v7, if possible, + * Do this in 2-4 insns. Use MOVW for v7, if possible, * to reduce the number of sequential conditional instructions. * Almost all guests have at least 4k pages, which means that we need * to clear at least 9 bits even for an 8-byte memory, which means it * isn't worth checking for an immediate operand for BIC. + * + * For unaligned accesses, test the page of the last unit of alignment. + * This leaves the least significant alignment bits unchanged, and of + * course must be zero. */ + t_addr = addrlo; + if (a_mask < s_mask) { + t_addr = TCG_REG_R0; + tcg_out_dat_imm(s, COND_AL, ARITH_ADD, t_addr, + addrlo, s_mask - a_mask); + } if (use_armv7_instructions && TARGET_PAGE_BITS <= 16) { - tcg_target_ulong mask = ~(TARGET_PAGE_MASK | ((1 << a_bits) - 1)); - - tcg_out_movi32(s, COND_AL, TCG_REG_TMP, mask); + tcg_out_movi32(s, COND_AL, TCG_REG_TMP, ~(TARGET_PAGE_MASK | a_mask)); tcg_out_dat_reg(s, COND_AL, ARITH_BIC, TCG_REG_TMP, - addrlo, TCG_REG_TMP, 0); + t_addr, TCG_REG_TMP, 0); tcg_out_dat_reg(s, COND_AL, ARITH_CMP, 0, TCG_REG_R2, TCG_REG_TMP, 0); } else { - if (a_bits) { - tcg_out_dat_imm(s, COND_AL, ARITH_TST, 0, addrlo, - (1 << a_bits) - 1); + if (a_mask) { + tcg_debug_assert(a_mask <= 0xff); + tcg_out_dat_imm(s, COND_AL, ARITH_TST, 0, addrlo, a_mask); } - tcg_out_dat_reg(s, COND_AL, ARITH_MOV, TCG_REG_TMP, 0, addrlo, + tcg_out_dat_reg(s, COND_AL, ARITH_MOV, TCG_REG_TMP, 0, t_addr, SHIFT_IMM_LSR(TARGET_PAGE_BITS)); - tcg_out_dat_reg(s, (a_bits ? COND_EQ : COND_AL), ARITH_CMP, + tcg_out_dat_reg(s, (a_mask ? COND_EQ : COND_AL), ARITH_CMP, 0, TCG_REG_R2, TCG_REG_TMP, SHIFT_IMM_LSL(TARGET_PAGE_BITS)); } |