Richard Henderson <richard.hender...@linaro.org> writes:
> AArch64 has both sign and zero-extending addressing modes, which
> means that either treatment of guest addresses is equally efficient.
> Enabling this for AArch64 gives us testing of the feature in CI.
So which guests front ends will exercise this backend? I realise you
never mentioned it in the cover letter. Is this something we can
exercise in 32 bit user mode tests?
> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
> ---
> tcg/aarch64/tcg-target-sa32.h | 8 ++++-
> tcg/aarch64/tcg-target.c.inc | 68 ++++++++++++++++++++++-------------
> 2 files changed, 51 insertions(+), 25 deletions(-)
>
> diff --git a/tcg/aarch64/tcg-target-sa32.h b/tcg/aarch64/tcg-target-sa32.h
> index cb185b1526..c99e502e4c 100644
> --- a/tcg/aarch64/tcg-target-sa32.h
> +++ b/tcg/aarch64/tcg-target-sa32.h
> @@ -1 +1,7 @@
> -#define TCG_TARGET_SIGNED_ADDR32 0
> +/*
> + * AArch64 has both SXTW and UXTW addressing modes, which means that
> + * it is agnostic to how guest addresses should be represented.
> + * Because aarch64 is more common than the other hosts that will
> + * want to use this feature, enable it for continuous testing.
> + */
> +#define TCG_TARGET_SIGNED_ADDR32 1
> diff --git a/tcg/aarch64/tcg-target.c.inc b/tcg/aarch64/tcg-target.c.inc
> index 5edca8d44d..88b2963f9d 100644
> --- a/tcg/aarch64/tcg-target.c.inc
> +++ b/tcg/aarch64/tcg-target.c.inc
> @@ -12,6 +12,7 @@
>
> #include "../tcg-pool.c.inc"
> #include "qemu/bitops.h"
> +#include "tcg-target-sa32.h"
>
> /* We're going to re-use TCGType in setting of the SF bit, which controls
> the size of the operation performed. If we know the values match, it
> @@ -804,12 +805,12 @@ static void tcg_out_insn_3617(TCGContext *s,
> AArch64Insn insn, bool q,
> }
>
> static void tcg_out_insn_3310(TCGContext *s, AArch64Insn insn,
> - TCGReg rd, TCGReg base, TCGType ext,
> + TCGReg rd, TCGReg base, int option,
> TCGReg regoff)
> {
> /* Note the AArch64Insn constants above are for C3.3.12. Adjust. */
> tcg_out32(s, insn | I3312_TO_I3310 | regoff << 16 |
> - 0x4000 | ext << 13 | base << 5 | (rd & 0x1f));
> + option << 13 | base << 5 | (rd & 0x1f));
> }
>
> static void tcg_out_insn_3312(TCGContext *s, AArch64Insn insn,
> @@ -1124,7 +1125,7 @@ static void tcg_out_ldst(TCGContext *s, AArch64Insn
> insn, TCGReg rd,
>
> /* Worst-case scenario, move offset to temp register, use reg offset. */
> tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_TMP, offset);
> - tcg_out_ldst_r(s, insn, rd, rn, TCG_TYPE_I64, TCG_REG_TMP);
> + tcg_out_ldst_r(s, insn, rd, rn, 3 /* LSL #0 */, TCG_REG_TMP);
> }
>
> static bool tcg_out_mov(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg)
> @@ -1718,34 +1719,34 @@ static void tcg_out_tlb_read(TCGContext *s, TCGReg
> addr_reg, MemOp opc,
>
> static void tcg_out_qemu_ld_direct(TCGContext *s, MemOp memop, TCGType ext,
> TCGReg data_r, TCGReg addr_r,
> - TCGType otype, TCGReg off_r)
> + int option, TCGReg off_r)
> {
> /* Byte swapping is left to middle-end expansion. */
> tcg_debug_assert((memop & MO_BSWAP) == 0);
>
> switch (memop & MO_SSIZE) {
> case MO_UB:
> - tcg_out_ldst_r(s, I3312_LDRB, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_LDRB, data_r, addr_r, option, off_r);
> break;
> case MO_SB:
> tcg_out_ldst_r(s, ext ? I3312_LDRSBX : I3312_LDRSBW,
> - data_r, addr_r, otype, off_r);
> + data_r, addr_r, option, off_r);
> break;
> case MO_UW:
> - tcg_out_ldst_r(s, I3312_LDRH, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_LDRH, data_r, addr_r, option, off_r);
> break;
> case MO_SW:
> tcg_out_ldst_r(s, (ext ? I3312_LDRSHX : I3312_LDRSHW),
> - data_r, addr_r, otype, off_r);
> + data_r, addr_r, option, off_r);
> break;
> case MO_UL:
> - tcg_out_ldst_r(s, I3312_LDRW, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_LDRW, data_r, addr_r, option, off_r);
> break;
> case MO_SL:
> - tcg_out_ldst_r(s, I3312_LDRSWX, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_LDRSWX, data_r, addr_r, option, off_r);
> break;
> case MO_Q:
> - tcg_out_ldst_r(s, I3312_LDRX, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_LDRX, data_r, addr_r, option, off_r);
> break;
> default:
> tcg_abort();
> @@ -1754,50 +1755,68 @@ static void tcg_out_qemu_ld_direct(TCGContext *s,
> MemOp memop, TCGType ext,
>
> static void tcg_out_qemu_st_direct(TCGContext *s, MemOp memop,
> TCGReg data_r, TCGReg addr_r,
> - TCGType otype, TCGReg off_r)
> + int option, TCGReg off_r)
> {
> /* Byte swapping is left to middle-end expansion. */
> tcg_debug_assert((memop & MO_BSWAP) == 0);
>
> switch (memop & MO_SIZE) {
> case MO_8:
> - tcg_out_ldst_r(s, I3312_STRB, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_STRB, data_r, addr_r, option, off_r);
> break;
> case MO_16:
> - tcg_out_ldst_r(s, I3312_STRH, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_STRH, data_r, addr_r, option, off_r);
> break;
> case MO_32:
> - tcg_out_ldst_r(s, I3312_STRW, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_STRW, data_r, addr_r, option, off_r);
> break;
> case MO_64:
> - tcg_out_ldst_r(s, I3312_STRX, data_r, addr_r, otype, off_r);
> + tcg_out_ldst_r(s, I3312_STRX, data_r, addr_r, option, off_r);
> break;
> default:
> tcg_abort();
> }
> }
>
> +static int guest_ext_option(void)
> +{
> +#ifdef CONFIG_USER_ONLY
> + bool signed_addr32 = guest_base_signed_addr32;
> +#else
> + bool signed_addr32 = TCG_TARGET_SIGNED_ADDR32;
> +#endif
> +
> + if (TARGET_LONG_BITS == 64) {
> + return 3; /* LSL #0 */
> + } else if (signed_addr32) {
> + return 6; /* SXTW */
> + } else {
> + return 2; /* UXTW */
> + }
> +}
If this is is going to be a magic number we pass into our code
generation we could at least wrap it in a confined enum rather than a
bare int we chuck around.
> +
> static void tcg_out_qemu_ld(TCGContext *s, TCGReg data_reg, TCGReg addr_reg,
> MemOpIdx oi, TCGType ext)
> {
> MemOp memop = get_memop(oi);
> - const TCGType otype = TARGET_LONG_BITS == 64 ? TCG_TYPE_I64 :
> TCG_TYPE_I32;
> + int option = guest_ext_option();
> +
> #ifdef CONFIG_SOFTMMU
> unsigned mem_index = get_mmuidx(oi);
> tcg_insn_unit *label_ptr;
>
> tcg_out_tlb_read(s, addr_reg, memop, &label_ptr, mem_index, 1);
> tcg_out_qemu_ld_direct(s, memop, ext, data_reg,
> - TCG_REG_X1, otype, addr_reg);
> + TCG_REG_X1, option, addr_reg);
> add_qemu_ldst_label(s, true, oi, ext, data_reg, addr_reg,
> s->code_ptr, label_ptr);
> #else /* !CONFIG_SOFTMMU */
> if (USE_GUEST_BASE) {
> tcg_out_qemu_ld_direct(s, memop, ext, data_reg,
> - TCG_REG_GUEST_BASE, otype, addr_reg);
> + TCG_REG_GUEST_BASE, option, addr_reg);
> } else {
> tcg_out_qemu_ld_direct(s, memop, ext, data_reg,
> - addr_reg, TCG_TYPE_I64, TCG_REG_XZR);
> + addr_reg, option, TCG_REG_XZR);
> }
> #endif /* CONFIG_SOFTMMU */
> }
> @@ -1806,23 +1825,24 @@ static void tcg_out_qemu_st(TCGContext *s, TCGReg
> data_reg, TCGReg addr_reg,
> MemOpIdx oi)
> {
> MemOp memop = get_memop(oi);
> - const TCGType otype = TARGET_LONG_BITS == 64 ? TCG_TYPE_I64 :
> TCG_TYPE_I32;
> + int option = guest_ext_option();
> +
> #ifdef CONFIG_SOFTMMU
> unsigned mem_index = get_mmuidx(oi);
> tcg_insn_unit *label_ptr;
>
> tcg_out_tlb_read(s, addr_reg, memop, &label_ptr, mem_index, 0);
> tcg_out_qemu_st_direct(s, memop, data_reg,
> - TCG_REG_X1, otype, addr_reg);
> + TCG_REG_X1, option, addr_reg);
> add_qemu_ldst_label(s, false, oi, (memop & MO_SIZE)== MO_64,
> data_reg, addr_reg, s->code_ptr, label_ptr);
> #else /* !CONFIG_SOFTMMU */
> if (USE_GUEST_BASE) {
> tcg_out_qemu_st_direct(s, memop, data_reg,
> - TCG_REG_GUEST_BASE, otype, addr_reg);
> + TCG_REG_GUEST_BASE, option, addr_reg);
> } else {
> tcg_out_qemu_st_direct(s, memop, data_reg,
> - addr_reg, TCG_TYPE_I64, TCG_REG_XZR);
> + addr_reg, option, TCG_REG_XZR);
> }
> #endif /* CONFIG_SOFTMMU */
> }
--
Alex Bennée
