target-arm: A64: add support for ld/st with reg offset

This adds support for the load/store forms using a register 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 23:27:29 +00:00 committed by Peter Maydell
parent d5612f10a1
commit 229b7a05e3

View File

@ -404,6 +404,54 @@ static void do_fp_ld(DisasContext *s, int destidx, TCGv_i64 tcg_addr, int size)
tcg_temp_free_i64(tmphi);
}
/*
* This utility function is for doing register extension with an
* optional shift. You will likely want to pass a temporary for the
* destination register. See DecodeRegExtend() in the ARM ARM.
*/
static void ext_and_shift_reg(TCGv_i64 tcg_out, TCGv_i64 tcg_in,
int option, unsigned int shift)
{
int extsize = extract32(option, 0, 2);
bool is_signed = extract32(option, 2, 1);
if (is_signed) {
switch (extsize) {
case 0:
tcg_gen_ext8s_i64(tcg_out, tcg_in);
break;
case 1:
tcg_gen_ext16s_i64(tcg_out, tcg_in);
break;
case 2:
tcg_gen_ext32s_i64(tcg_out, tcg_in);
break;
case 3:
tcg_gen_mov_i64(tcg_out, tcg_in);
break;
}
} else {
switch (extsize) {
case 0:
tcg_gen_ext8u_i64(tcg_out, tcg_in);
break;
case 1:
tcg_gen_ext16u_i64(tcg_out, tcg_in);
break;
case 2:
tcg_gen_ext32u_i64(tcg_out, tcg_in);
break;
case 3:
tcg_gen_mov_i64(tcg_out, tcg_in);
break;
}
}
if (shift) {
tcg_gen_shli_i64(tcg_out, tcg_out, shift);
}
}
static inline void gen_check_sp_alignment(DisasContext *s)
{
/* The AArch64 architecture mandates that (if enabled via PSTATE
@ -901,6 +949,96 @@ static void disas_ldst_pair(DisasContext *s, uint32_t insn)
}
}
/*
* C3.3.10 Load/store (register offset)
*
* 31 30 29 27 26 25 24 23 22 21 20 16 15 13 12 11 10 9 5 4 0
* +----+-------+---+-----+-----+---+------+-----+--+-----+----+----+
* |size| 1 1 1 | V | 0 0 | opc | 1 | Rm | opt | S| 1 0 | 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
* V: 1 -> vector/simd
* opt: extend encoding (see DecodeRegExtend)
* S: if S=1 then scale (essentially index by sizeof(size))
* Rt: register to transfer into/out of
* Rn: address register or SP for base
* Rm: offset register or ZR for offset
*/
static void disas_ldst_reg_roffset(DisasContext *s, uint32_t insn)
{
int rt = extract32(insn, 0, 5);
int rn = extract32(insn, 5, 5);
int shift = extract32(insn, 12, 1);
int rm = extract32(insn, 16, 5);
int opc = extract32(insn, 22, 2);
int opt = extract32(insn, 13, 3);
int size = extract32(insn, 30, 2);
bool is_signed = false;
bool is_store = false;
bool is_extended = false;
bool is_vector = extract32(insn, 26, 1);
TCGv_i64 tcg_rm;
TCGv_i64 tcg_addr;
if (extract32(opt, 1, 1) == 0) {
unallocated_encoding(s);
return;
}
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);
tcg_rm = read_cpu_reg(s, rm, 1);
ext_and_shift_reg(tcg_rm, tcg_rm, opt, shift ? size : 0);
tcg_gen_add_i64(tcg_addr, tcg_addr, tcg_rm);
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);
}
}
}
/*
* C3.3.13 Load/store (unsigned immediate)
*
@ -983,7 +1121,11 @@ static void disas_ldst_reg(DisasContext *s, uint32_t insn)
{
switch (extract32(insn, 24, 2)) {
case 0:
if (extract32(insn, 21, 1) == 1 && extract32(insn, 10, 2) == 2) {
disas_ldst_reg_roffset(s, insn);
} else {
unsupported_encoding(s, insn);
}
break;
case 1:
disas_ldst_reg_unsigned_imm(s, insn);