[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v2] target/arm: Move minor arithmetic helpers out of helper.c
|
From: |
Alex Bennée |
|
Subject: |
Re: [PATCH v2] target/arm: Move minor arithmetic helpers out of helper.c |
|
Date: |
Fri, 10 Jan 2025 15:32:17 +0000 |
|
User-agent: |
mu4e 1.12.8; emacs 29.4 |
Peter Maydell <peter.maydell@linaro.org> writes:
> helper.c includes some small TCG helper functions used for mostly
> arithmetic instructions. These are TCG only and there's no need for
> them to be in the large and unwieldy helper.c. Move them out to
> their own source file in the tcg/ subdirectory, together with the
> op_addsub.h multiply-included template header that they use.
>
> Since we are moving op_addsub.h, we take the opportunity to
> give it a name which matches our convention for files which
> are not true header files but which are #included from other
> C files: op_addsub.c.inc.
>
> (Ironically, this means that helper.c no longer contains
> any TCG helper function definitions at all.)
What's left? It mostly looks like cpreg related stuff. I guess it could
become cpreg.c?
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Anyway:
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> ---
> v1->v2: rename op_addsub.h to op_addsub.c.inc.
> ---
> target/arm/helper.c | 285 -----------------
> target/arm/tcg/arith_helper.c | 296 ++++++++++++++++++
> .../arm/{op_addsub.h => tcg/op_addsub.c.inc} | 0
> target/arm/tcg/meson.build | 1 +
> 4 files changed, 297 insertions(+), 285 deletions(-)
> create mode 100644 target/arm/tcg/arith_helper.c
> rename target/arm/{op_addsub.h => tcg/op_addsub.c.inc} (100%)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 5b595f951b4..63997678513 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -17,11 +17,9 @@
> #include "qemu/main-loop.h"
> #include "qemu/timer.h"
> #include "qemu/bitops.h"
> -#include "qemu/crc32c.h"
> #include "qemu/qemu-print.h"
> #include "exec/exec-all.h"
> #include "exec/translation-block.h"
> -#include <zlib.h> /* for crc32 */
> #include "hw/irq.h"
> #include "system/cpu-timers.h"
> #include "system/kvm.h"
> @@ -10984,289 +10982,6 @@ ARMVAParameters aa64_va_parameters(CPUARMState
> *env, uint64_t va,
> };
> }
>
> -/*
> - * Note that signed overflow is undefined in C. The following routines are
> - * careful to use unsigned types where modulo arithmetic is required.
> - * Failure to do so _will_ break on newer gcc.
> - */
> -
> -/* Signed saturating arithmetic. */
> -
> -/* Perform 16-bit signed saturating addition. */
> -static inline uint16_t add16_sat(uint16_t a, uint16_t b)
> -{
> - uint16_t res;
> -
> - res = a + b;
> - if (((res ^ a) & 0x8000) && !((a ^ b) & 0x8000)) {
> - if (a & 0x8000) {
> - res = 0x8000;
> - } else {
> - res = 0x7fff;
> - }
> - }
> - return res;
> -}
> -
> -/* Perform 8-bit signed saturating addition. */
> -static inline uint8_t add8_sat(uint8_t a, uint8_t b)
> -{
> - uint8_t res;
> -
> - res = a + b;
> - if (((res ^ a) & 0x80) && !((a ^ b) & 0x80)) {
> - if (a & 0x80) {
> - res = 0x80;
> - } else {
> - res = 0x7f;
> - }
> - }
> - return res;
> -}
> -
> -/* Perform 16-bit signed saturating subtraction. */
> -static inline uint16_t sub16_sat(uint16_t a, uint16_t b)
> -{
> - uint16_t res;
> -
> - res = a - b;
> - if (((res ^ a) & 0x8000) && ((a ^ b) & 0x8000)) {
> - if (a & 0x8000) {
> - res = 0x8000;
> - } else {
> - res = 0x7fff;
> - }
> - }
> - return res;
> -}
> -
> -/* Perform 8-bit signed saturating subtraction. */
> -static inline uint8_t sub8_sat(uint8_t a, uint8_t b)
> -{
> - uint8_t res;
> -
> - res = a - b;
> - if (((res ^ a) & 0x80) && ((a ^ b) & 0x80)) {
> - if (a & 0x80) {
> - res = 0x80;
> - } else {
> - res = 0x7f;
> - }
> - }
> - return res;
> -}
> -
> -#define ADD16(a, b, n) RESULT(add16_sat(a, b), n, 16);
> -#define SUB16(a, b, n) RESULT(sub16_sat(a, b), n, 16);
> -#define ADD8(a, b, n) RESULT(add8_sat(a, b), n, 8);
> -#define SUB8(a, b, n) RESULT(sub8_sat(a, b), n, 8);
> -#define PFX q
> -
> -#include "op_addsub.h"
> -
> -/* Unsigned saturating arithmetic. */
> -static inline uint16_t add16_usat(uint16_t a, uint16_t b)
> -{
> - uint16_t res;
> - res = a + b;
> - if (res < a) {
> - res = 0xffff;
> - }
> - return res;
> -}
> -
> -static inline uint16_t sub16_usat(uint16_t a, uint16_t b)
> -{
> - if (a > b) {
> - return a - b;
> - } else {
> - return 0;
> - }
> -}
> -
> -static inline uint8_t add8_usat(uint8_t a, uint8_t b)
> -{
> - uint8_t res;
> - res = a + b;
> - if (res < a) {
> - res = 0xff;
> - }
> - return res;
> -}
> -
> -static inline uint8_t sub8_usat(uint8_t a, uint8_t b)
> -{
> - if (a > b) {
> - return a - b;
> - } else {
> - return 0;
> - }
> -}
> -
> -#define ADD16(a, b, n) RESULT(add16_usat(a, b), n, 16);
> -#define SUB16(a, b, n) RESULT(sub16_usat(a, b), n, 16);
> -#define ADD8(a, b, n) RESULT(add8_usat(a, b), n, 8);
> -#define SUB8(a, b, n) RESULT(sub8_usat(a, b), n, 8);
> -#define PFX uq
> -
> -#include "op_addsub.h"
> -
> -/* Signed modulo arithmetic. */
> -#define SARITH16(a, b, n, op) do { \
> - int32_t sum; \
> - sum = (int32_t)(int16_t)(a) op (int32_t)(int16_t)(b); \
> - RESULT(sum, n, 16); \
> - if (sum >= 0) \
> - ge |= 3 << (n * 2); \
> - } while (0)
> -
> -#define SARITH8(a, b, n, op) do { \
> - int32_t sum; \
> - sum = (int32_t)(int8_t)(a) op (int32_t)(int8_t)(b); \
> - RESULT(sum, n, 8); \
> - if (sum >= 0) \
> - ge |= 1 << n; \
> - } while (0)
> -
> -
> -#define ADD16(a, b, n) SARITH16(a, b, n, +)
> -#define SUB16(a, b, n) SARITH16(a, b, n, -)
> -#define ADD8(a, b, n) SARITH8(a, b, n, +)
> -#define SUB8(a, b, n) SARITH8(a, b, n, -)
> -#define PFX s
> -#define ARITH_GE
> -
> -#include "op_addsub.h"
> -
> -/* Unsigned modulo arithmetic. */
> -#define ADD16(a, b, n) do { \
> - uint32_t sum; \
> - sum = (uint32_t)(uint16_t)(a) + (uint32_t)(uint16_t)(b); \
> - RESULT(sum, n, 16); \
> - if ((sum >> 16) == 1) \
> - ge |= 3 << (n * 2); \
> - } while (0)
> -
> -#define ADD8(a, b, n) do { \
> - uint32_t sum; \
> - sum = (uint32_t)(uint8_t)(a) + (uint32_t)(uint8_t)(b); \
> - RESULT(sum, n, 8); \
> - if ((sum >> 8) == 1) \
> - ge |= 1 << n; \
> - } while (0)
> -
> -#define SUB16(a, b, n) do { \
> - uint32_t sum; \
> - sum = (uint32_t)(uint16_t)(a) - (uint32_t)(uint16_t)(b); \
> - RESULT(sum, n, 16); \
> - if ((sum >> 16) == 0) \
> - ge |= 3 << (n * 2); \
> - } while (0)
> -
> -#define SUB8(a, b, n) do { \
> - uint32_t sum; \
> - sum = (uint32_t)(uint8_t)(a) - (uint32_t)(uint8_t)(b); \
> - RESULT(sum, n, 8); \
> - if ((sum >> 8) == 0) \
> - ge |= 1 << n; \
> - } while (0)
> -
> -#define PFX u
> -#define ARITH_GE
> -
> -#include "op_addsub.h"
> -
> -/* Halved signed arithmetic. */
> -#define ADD16(a, b, n) \
> - RESULT(((int32_t)(int16_t)(a) + (int32_t)(int16_t)(b)) >> 1, n, 16)
> -#define SUB16(a, b, n) \
> - RESULT(((int32_t)(int16_t)(a) - (int32_t)(int16_t)(b)) >> 1, n, 16)
> -#define ADD8(a, b, n) \
> - RESULT(((int32_t)(int8_t)(a) + (int32_t)(int8_t)(b)) >> 1, n, 8)
> -#define SUB8(a, b, n) \
> - RESULT(((int32_t)(int8_t)(a) - (int32_t)(int8_t)(b)) >> 1, n, 8)
> -#define PFX sh
> -
> -#include "op_addsub.h"
> -
> -/* Halved unsigned arithmetic. */
> -#define ADD16(a, b, n) \
> - RESULT(((uint32_t)(uint16_t)(a) + (uint32_t)(uint16_t)(b)) >> 1, n, 16)
> -#define SUB16(a, b, n) \
> - RESULT(((uint32_t)(uint16_t)(a) - (uint32_t)(uint16_t)(b)) >> 1, n, 16)
> -#define ADD8(a, b, n) \
> - RESULT(((uint32_t)(uint8_t)(a) + (uint32_t)(uint8_t)(b)) >> 1, n, 8)
> -#define SUB8(a, b, n) \
> - RESULT(((uint32_t)(uint8_t)(a) - (uint32_t)(uint8_t)(b)) >> 1, n, 8)
> -#define PFX uh
> -
> -#include "op_addsub.h"
> -
> -static inline uint8_t do_usad(uint8_t a, uint8_t b)
> -{
> - if (a > b) {
> - return a - b;
> - } else {
> - return b - a;
> - }
> -}
> -
> -/* Unsigned sum of absolute byte differences. */
> -uint32_t HELPER(usad8)(uint32_t a, uint32_t b)
> -{
> - uint32_t sum;
> - sum = do_usad(a, b);
> - sum += do_usad(a >> 8, b >> 8);
> - sum += do_usad(a >> 16, b >> 16);
> - sum += do_usad(a >> 24, b >> 24);
> - return sum;
> -}
> -
> -/* For ARMv6 SEL instruction. */
> -uint32_t HELPER(sel_flags)(uint32_t flags, uint32_t a, uint32_t b)
> -{
> - uint32_t mask;
> -
> - mask = 0;
> - if (flags & 1) {
> - mask |= 0xff;
> - }
> - if (flags & 2) {
> - mask |= 0xff00;
> - }
> - if (flags & 4) {
> - mask |= 0xff0000;
> - }
> - if (flags & 8) {
> - mask |= 0xff000000;
> - }
> - return (a & mask) | (b & ~mask);
> -}
> -
> -/*
> - * CRC helpers.
> - * The upper bytes of val (above the number specified by 'bytes') must have
> - * been zeroed out by the caller.
> - */
> -uint32_t HELPER(crc32)(uint32_t acc, uint32_t val, uint32_t bytes)
> -{
> - uint8_t buf[4];
> -
> - stl_le_p(buf, val);
> -
> - /* zlib crc32 converts the accumulator and output to one's complement.
> */
> - return crc32(acc ^ 0xffffffff, buf, bytes) ^ 0xffffffff;
> -}
> -
> -uint32_t HELPER(crc32c)(uint32_t acc, uint32_t val, uint32_t bytes)
> -{
> - uint8_t buf[4];
> -
> - stl_le_p(buf, val);
> -
> - /* Linux crc32c converts the output to one's complement. */
> - return crc32c(acc, buf, bytes) ^ 0xffffffff;
> -}
>
> /*
> * Return the exception level to which FP-disabled exceptions should
> diff --git a/target/arm/tcg/arith_helper.c b/target/arm/tcg/arith_helper.c
> new file mode 100644
> index 00000000000..9a555c7966c
> --- /dev/null
> +++ b/target/arm/tcg/arith_helper.c
> @@ -0,0 +1,296 @@
> +/*
> + * ARM generic helpers for various arithmetical operations.
> + *
> + * This code is licensed under the GNU GPL v2 or later.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#include "qemu/osdep.h"
> +#include "cpu.h"
> +#include "exec/helper-proto.h"
> +#include "qemu/crc32c.h"
> +#include <zlib.h> /* for crc32 */
> +
> +/*
> + * Note that signed overflow is undefined in C. The following routines are
> + * careful to use unsigned types where modulo arithmetic is required.
> + * Failure to do so _will_ break on newer gcc.
> + */
> +
> +/* Signed saturating arithmetic. */
> +
> +/* Perform 16-bit signed saturating addition. */
> +static inline uint16_t add16_sat(uint16_t a, uint16_t b)
> +{
> + uint16_t res;
> +
> + res = a + b;
> + if (((res ^ a) & 0x8000) && !((a ^ b) & 0x8000)) {
> + if (a & 0x8000) {
> + res = 0x8000;
> + } else {
> + res = 0x7fff;
> + }
> + }
> + return res;
> +}
> +
> +/* Perform 8-bit signed saturating addition. */
> +static inline uint8_t add8_sat(uint8_t a, uint8_t b)
> +{
> + uint8_t res;
> +
> + res = a + b;
> + if (((res ^ a) & 0x80) && !((a ^ b) & 0x80)) {
> + if (a & 0x80) {
> + res = 0x80;
> + } else {
> + res = 0x7f;
> + }
> + }
> + return res;
> +}
> +
> +/* Perform 16-bit signed saturating subtraction. */
> +static inline uint16_t sub16_sat(uint16_t a, uint16_t b)
> +{
> + uint16_t res;
> +
> + res = a - b;
> + if (((res ^ a) & 0x8000) && ((a ^ b) & 0x8000)) {
> + if (a & 0x8000) {
> + res = 0x8000;
> + } else {
> + res = 0x7fff;
> + }
> + }
> + return res;
> +}
> +
> +/* Perform 8-bit signed saturating subtraction. */
> +static inline uint8_t sub8_sat(uint8_t a, uint8_t b)
> +{
> + uint8_t res;
> +
> + res = a - b;
> + if (((res ^ a) & 0x80) && ((a ^ b) & 0x80)) {
> + if (a & 0x80) {
> + res = 0x80;
> + } else {
> + res = 0x7f;
> + }
> + }
> + return res;
> +}
> +
> +#define ADD16(a, b, n) RESULT(add16_sat(a, b), n, 16);
> +#define SUB16(a, b, n) RESULT(sub16_sat(a, b), n, 16);
> +#define ADD8(a, b, n) RESULT(add8_sat(a, b), n, 8);
> +#define SUB8(a, b, n) RESULT(sub8_sat(a, b), n, 8);
> +#define PFX q
> +
> +#include "op_addsub.c.inc"
> +
> +/* Unsigned saturating arithmetic. */
> +static inline uint16_t add16_usat(uint16_t a, uint16_t b)
> +{
> + uint16_t res;
> + res = a + b;
> + if (res < a) {
> + res = 0xffff;
> + }
> + return res;
> +}
> +
> +static inline uint16_t sub16_usat(uint16_t a, uint16_t b)
> +{
> + if (a > b) {
> + return a - b;
> + } else {
> + return 0;
> + }
> +}
> +
> +static inline uint8_t add8_usat(uint8_t a, uint8_t b)
> +{
> + uint8_t res;
> + res = a + b;
> + if (res < a) {
> + res = 0xff;
> + }
> + return res;
> +}
> +
> +static inline uint8_t sub8_usat(uint8_t a, uint8_t b)
> +{
> + if (a > b) {
> + return a - b;
> + } else {
> + return 0;
> + }
> +}
> +
> +#define ADD16(a, b, n) RESULT(add16_usat(a, b), n, 16);
> +#define SUB16(a, b, n) RESULT(sub16_usat(a, b), n, 16);
> +#define ADD8(a, b, n) RESULT(add8_usat(a, b), n, 8);
> +#define SUB8(a, b, n) RESULT(sub8_usat(a, b), n, 8);
> +#define PFX uq
> +
> +#include "op_addsub.c.inc"
> +
> +/* Signed modulo arithmetic. */
> +#define SARITH16(a, b, n, op) do { \
> + int32_t sum; \
> + sum = (int32_t)(int16_t)(a) op (int32_t)(int16_t)(b); \
> + RESULT(sum, n, 16); \
> + if (sum >= 0) \
> + ge |= 3 << (n * 2); \
> + } while (0)
> +
> +#define SARITH8(a, b, n, op) do { \
> + int32_t sum; \
> + sum = (int32_t)(int8_t)(a) op (int32_t)(int8_t)(b); \
> + RESULT(sum, n, 8); \
> + if (sum >= 0) \
> + ge |= 1 << n; \
> + } while (0)
> +
> +
> +#define ADD16(a, b, n) SARITH16(a, b, n, +)
> +#define SUB16(a, b, n) SARITH16(a, b, n, -)
> +#define ADD8(a, b, n) SARITH8(a, b, n, +)
> +#define SUB8(a, b, n) SARITH8(a, b, n, -)
> +#define PFX s
> +#define ARITH_GE
> +
> +#include "op_addsub.c.inc"
> +
> +/* Unsigned modulo arithmetic. */
> +#define ADD16(a, b, n) do { \
> + uint32_t sum; \
> + sum = (uint32_t)(uint16_t)(a) + (uint32_t)(uint16_t)(b); \
> + RESULT(sum, n, 16); \
> + if ((sum >> 16) == 1) \
> + ge |= 3 << (n * 2); \
> + } while (0)
> +
> +#define ADD8(a, b, n) do { \
> + uint32_t sum; \
> + sum = (uint32_t)(uint8_t)(a) + (uint32_t)(uint8_t)(b); \
> + RESULT(sum, n, 8); \
> + if ((sum >> 8) == 1) \
> + ge |= 1 << n; \
> + } while (0)
> +
> +#define SUB16(a, b, n) do { \
> + uint32_t sum; \
> + sum = (uint32_t)(uint16_t)(a) - (uint32_t)(uint16_t)(b); \
> + RESULT(sum, n, 16); \
> + if ((sum >> 16) == 0) \
> + ge |= 3 << (n * 2); \
> + } while (0)
> +
> +#define SUB8(a, b, n) do { \
> + uint32_t sum; \
> + sum = (uint32_t)(uint8_t)(a) - (uint32_t)(uint8_t)(b); \
> + RESULT(sum, n, 8); \
> + if ((sum >> 8) == 0) \
> + ge |= 1 << n; \
> + } while (0)
> +
> +#define PFX u
> +#define ARITH_GE
> +
> +#include "op_addsub.c.inc"
> +
> +/* Halved signed arithmetic. */
> +#define ADD16(a, b, n) \
> + RESULT(((int32_t)(int16_t)(a) + (int32_t)(int16_t)(b)) >> 1, n, 16)
> +#define SUB16(a, b, n) \
> + RESULT(((int32_t)(int16_t)(a) - (int32_t)(int16_t)(b)) >> 1, n, 16)
> +#define ADD8(a, b, n) \
> + RESULT(((int32_t)(int8_t)(a) + (int32_t)(int8_t)(b)) >> 1, n, 8)
> +#define SUB8(a, b, n) \
> + RESULT(((int32_t)(int8_t)(a) - (int32_t)(int8_t)(b)) >> 1, n, 8)
> +#define PFX sh
> +
> +#include "op_addsub.c.inc"
> +
> +/* Halved unsigned arithmetic. */
> +#define ADD16(a, b, n) \
> + RESULT(((uint32_t)(uint16_t)(a) + (uint32_t)(uint16_t)(b)) >> 1, n, 16)
> +#define SUB16(a, b, n) \
> + RESULT(((uint32_t)(uint16_t)(a) - (uint32_t)(uint16_t)(b)) >> 1, n, 16)
> +#define ADD8(a, b, n) \
> + RESULT(((uint32_t)(uint8_t)(a) + (uint32_t)(uint8_t)(b)) >> 1, n, 8)
> +#define SUB8(a, b, n) \
> + RESULT(((uint32_t)(uint8_t)(a) - (uint32_t)(uint8_t)(b)) >> 1, n, 8)
> +#define PFX uh
> +
> +#include "op_addsub.c.inc"
> +
> +static inline uint8_t do_usad(uint8_t a, uint8_t b)
> +{
> + if (a > b) {
> + return a - b;
> + } else {
> + return b - a;
> + }
> +}
> +
> +/* Unsigned sum of absolute byte differences. */
> +uint32_t HELPER(usad8)(uint32_t a, uint32_t b)
> +{
> + uint32_t sum;
> + sum = do_usad(a, b);
> + sum += do_usad(a >> 8, b >> 8);
> + sum += do_usad(a >> 16, b >> 16);
> + sum += do_usad(a >> 24, b >> 24);
> + return sum;
> +}
> +
> +/* For ARMv6 SEL instruction. */
> +uint32_t HELPER(sel_flags)(uint32_t flags, uint32_t a, uint32_t b)
> +{
> + uint32_t mask;
> +
> + mask = 0;
> + if (flags & 1) {
> + mask |= 0xff;
> + }
> + if (flags & 2) {
> + mask |= 0xff00;
> + }
> + if (flags & 4) {
> + mask |= 0xff0000;
> + }
> + if (flags & 8) {
> + mask |= 0xff000000;
> + }
> + return (a & mask) | (b & ~mask);
> +}
> +
> +/*
> + * CRC helpers.
> + * The upper bytes of val (above the number specified by 'bytes') must have
> + * been zeroed out by the caller.
> + */
> +uint32_t HELPER(crc32)(uint32_t acc, uint32_t val, uint32_t bytes)
> +{
> + uint8_t buf[4];
> +
> + stl_le_p(buf, val);
> +
> + /* zlib crc32 converts the accumulator and output to one's complement.
> */
> + return crc32(acc ^ 0xffffffff, buf, bytes) ^ 0xffffffff;
> +}
> +
> +uint32_t HELPER(crc32c)(uint32_t acc, uint32_t val, uint32_t bytes)
> +{
> + uint8_t buf[4];
> +
> + stl_le_p(buf, val);
> +
> + /* Linux crc32c converts the output to one's complement. */
> + return crc32c(acc, buf, bytes) ^ 0xffffffff;
> +}
> diff --git a/target/arm/op_addsub.h b/target/arm/tcg/op_addsub.c.inc
> similarity index 100%
> rename from target/arm/op_addsub.h
> rename to target/arm/tcg/op_addsub.c.inc
> diff --git a/target/arm/tcg/meson.build b/target/arm/tcg/meson.build
> index 09238989c5a..1f9077c372c 100644
> --- a/target/arm/tcg/meson.build
> +++ b/target/arm/tcg/meson.build
> @@ -40,6 +40,7 @@ arm_ss.add(files(
> 'tlb_helper.c',
> 'vec_helper.c',
> 'tlb-insns.c',
> + 'arith_helper.c',
> ))
>
> arm_ss.add(when: 'TARGET_AARCH64', if_true: files(
--
Alex Bennée
Virtualisation Tech Lead @ Linaro