target-arm: A64: add support for ld/st unsigned imm

This adds support for the forms of ld/st with a 12 bit
unsigned immediate offset.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Alex Bennée 2013-12-23 23:27:28 +00:00 committed by Peter Maydell
parent 4a08d4758f
commit d5612f10a1

View file

@ -901,10 +901,97 @@ static void disas_ldst_pair(DisasContext *s, uint32_t insn)
}
}
/*
* C3.3.13 Load/store (unsigned immediate)
*
* 31 30 29 27 26 25 24 23 22 21 10 9 5
* +----+-------+---+-----+-----+------------+-------+------+
* |size| 1 1 1 | V | 0 1 | opc | imm12 | Rn | Rt |
* +----+-------+---+-----+-----+------------+-------+------+
*
* For non-vector:
* size: 00-> byte, 01 -> 16 bit, 10 -> 32bit, 11 -> 64bit
* opc: 00 -> store, 01 -> loadu, 10 -> loads 64, 11 -> loads 32
* For vector:
* size is opc<1>:size<1:0> so 100 -> 128 bit; 110 and 111 unallocated
* opc<0>: 0 -> store, 1 -> load
* Rn: base address register (inc SP)
* Rt: target register
*/
static void disas_ldst_reg_unsigned_imm(DisasContext *s, uint32_t insn)
{
int rt = extract32(insn, 0, 5);
int rn = extract32(insn, 5, 5);
unsigned int imm12 = extract32(insn, 10, 12);
bool is_vector = extract32(insn, 26, 1);
int size = extract32(insn, 30, 2);
int opc = extract32(insn, 22, 2);
unsigned int offset;
TCGv_i64 tcg_addr;
bool is_store;
bool is_signed = false;
bool is_extended = false;
if (is_vector) {
size |= (opc & 2) << 1;
if (size > 4) {
unallocated_encoding(s);
return;
}
is_store = !extract32(opc, 0, 1);
} else {
if (size == 3 && opc == 2) {
/* PRFM - prefetch */
return;
}
if (opc == 3 && size > 1) {
unallocated_encoding(s);
return;
}
is_store = (opc == 0);
is_signed = extract32(opc, 1, 1);
is_extended = (size < 3) && extract32(opc, 0, 1);
}
if (rn == 31) {
gen_check_sp_alignment(s);
}
tcg_addr = read_cpu_reg_sp(s, rn, 1);
offset = imm12 << size;
tcg_gen_addi_i64(tcg_addr, tcg_addr, offset);
if (is_vector) {
if (is_store) {
do_fp_st(s, rt, tcg_addr, size);
} else {
do_fp_ld(s, rt, tcg_addr, size);
}
} else {
TCGv_i64 tcg_rt = cpu_reg(s, rt);
if (is_store) {
do_gpr_st(s, tcg_rt, tcg_addr, size);
} else {
do_gpr_ld(s, tcg_rt, tcg_addr, size, is_signed, is_extended);
}
}
}
/* Load/store register (all forms) */
static void disas_ldst_reg(DisasContext *s, uint32_t insn)
{
unsupported_encoding(s, insn);
switch (extract32(insn, 24, 2)) {
case 0:
unsupported_encoding(s, insn);
break;
case 1:
disas_ldst_reg_unsigned_imm(s, insn);
break;
default:
unallocated_encoding(s);
break;
}
}
/* AdvSIMD load/store multiple structures */