From c97e8977dcacb3fa8362ee28bcee75ceb01fceaa Mon Sep 17 00:00:00 2001 From: Zack Buhman Date: Fri, 5 Apr 2024 15:17:39 -1000 Subject: [PATCH] target/sh4: Fix mac.l with saturation enabled MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The saturation arithmetic logic in helper_macl is not correct. I tested and verified this behavior on a SH7091. Signed-off-by: Zack Buhman Message-Id: <20240404162641.27528-2-zack@buhman.org> [rth: Reformat helper_macl, add a test case.] Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé --- target/sh4/helper.h | 2 +- target/sh4/op_helper.c | 23 ++++++------ tests/tcg/sh4/Makefile.target | 5 +++ tests/tcg/sh4/test-macl.c | 67 +++++++++++++++++++++++++++++++++++ 4 files changed, 86 insertions(+), 11 deletions(-) create mode 100644 tests/tcg/sh4/test-macl.c diff --git a/target/sh4/helper.h b/target/sh4/helper.h index 8d792f6b55..64056e4a39 100644 --- a/target/sh4/helper.h +++ b/target/sh4/helper.h @@ -11,7 +11,7 @@ DEF_HELPER_3(movcal, void, env, i32, i32) DEF_HELPER_1(discard_movcal_backup, void, env) DEF_HELPER_2(ocbi, void, env, i32) -DEF_HELPER_3(macl, void, env, i32, i32) +DEF_HELPER_3(macl, void, env, s32, s32) DEF_HELPER_3(macw, void, env, i32, i32) DEF_HELPER_2(ld_fpscr, void, env, i32) diff --git a/target/sh4/op_helper.c b/target/sh4/op_helper.c index 4559d0d376..d0bae0cc00 100644 --- a/target/sh4/op_helper.c +++ b/target/sh4/op_helper.c @@ -158,20 +158,23 @@ void helper_ocbi(CPUSH4State *env, uint32_t address) } } -void helper_macl(CPUSH4State *env, uint32_t arg0, uint32_t arg1) +void helper_macl(CPUSH4State *env, int32_t arg0, int32_t arg1) { + const int64_t min = -(1ll << 47); + const int64_t max = (1ll << 47) - 1; + int64_t mul = (int64_t)arg0 * arg1; + int64_t mac = env->mac; int64_t res; - res = ((uint64_t) env->mach << 32) | env->macl; - res += (int64_t) (int32_t) arg0 *(int64_t) (int32_t) arg1; - env->mach = (res >> 32) & 0xffffffff; - env->macl = res & 0xffffffff; - if (env->sr & (1u << SR_S)) { - if (res < 0) - env->mach |= 0xffff0000; - else - env->mach &= 0x00007fff; + if (!(env->sr & (1u << SR_S))) { + res = mac + mul; + } else if (sadd64_overflow(mac, mul, &res)) { + res = mac < 0 ? min : max; + } else { + res = MIN(MAX(res, min), max); } + + env->mac = res; } void helper_macw(CPUSH4State *env, uint32_t arg0, uint32_t arg1) diff --git a/tests/tcg/sh4/Makefile.target b/tests/tcg/sh4/Makefile.target index 16eaa850a8..9a11c10924 100644 --- a/tests/tcg/sh4/Makefile.target +++ b/tests/tcg/sh4/Makefile.target @@ -9,3 +9,8 @@ run-signals: signals $(call skip-test, $<, "BROKEN") run-plugin-signals-with-%: $(call skip-test, $<, "BROKEN") + +VPATH += $(SRC_PATH)/tests/tcg/sh4 + +test-macl: CFLAGS += -O -g +TESTS += test-macl diff --git a/tests/tcg/sh4/test-macl.c b/tests/tcg/sh4/test-macl.c new file mode 100644 index 0000000000..b66c854365 --- /dev/null +++ b/tests/tcg/sh4/test-macl.c @@ -0,0 +1,67 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#include +#include +#include + +#define MACL_S_MIN (-(1ll << 47)) +#define MACL_S_MAX ((1ll << 47) - 1) + +int64_t mac_l(int64_t mac, const int32_t *a, const int32_t *b) +{ + register uint32_t macl __asm__("macl") = mac; + register uint32_t mach __asm__("mach") = mac >> 32; + + asm volatile("mac.l @%0+,@%1+" + : "+r"(a), "+r"(b), "+x"(macl), "+x"(mach)); + + return ((uint64_t)mach << 32) | macl; +} + +typedef struct { + int64_t mac; + int32_t a, b; + int64_t res[2]; +} Test; + +__attribute__((noinline)) +void test(const Test *t, int sat) +{ + int64_t res; + + if (sat) { + asm volatile("sets"); + } else { + asm volatile("clrs"); + } + res = mac_l(t->mac, &t->a, &t->b); + + if (res != t->res[sat]) { + fprintf(stderr, "%#llx + (%#x * %#x) = %#llx -- got %#llx\n", + t->mac, t->a, t->b, t->res[sat], res); + abort(); + } +} + +int main() +{ + static const Test tests[] = { + { 0x00007fff12345678ll, INT32_MAX, INT32_MAX, + { 0x40007ffe12345679ll, MACL_S_MAX } }, + { MACL_S_MIN, -1, 1, + { 0xffff7fffffffffffll, MACL_S_MIN } }, + { INT64_MIN, -1, 1, + { INT64_MAX, MACL_S_MIN } }, + { 0x00007fff00000000ll, INT32_MAX, INT32_MAX, + { 0x40007ffe00000001ll, MACL_S_MAX } }, + { 4, 1, 2, { 6, 6 } }, + { -4, -1, -2, { -2, -2 } }, + }; + + for (int i = 0; i < sizeof(tests) / sizeof(tests[0]); ++i) { + for (int j = 0; j < 2; ++j) { + test(&tests[i], j); + } + } + return 0; +}