/* * AArch64 specific helpers * * Copyright (c) 2013 Alexander Graf * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, see . */ #include "qemu/osdep.h" #include "cpu.h" #include "exec/gdbstub.h" #include "exec/helper-proto.h" #include "qemu/host-utils.h" #include "qemu/log.h" #include "sysemu/sysemu.h" #include "qemu/bitops.h" #include "internals.h" #include "qemu/crc32c.h" #include "exec/exec-all.h" #include "exec/cpu_ldst.h" #include "qemu/int128.h" #include "tcg.h" #include "fpu/softfloat.h" #include /* For crc32 */ /* C2.4.7 Multiply and divide */ /* special cases for 0 and LLONG_MIN are mandated by the standard */ uint64_t HELPER(udiv64)(uint64_t num, uint64_t den) { if (den == 0) { return 0; } return num / den; } int64_t HELPER(sdiv64)(int64_t num, int64_t den) { if (den == 0) { return 0; } if (num == LLONG_MIN && den == -1) { return LLONG_MIN; } return num / den; } uint64_t HELPER(rbit64)(uint64_t x) { return revbit64(x); } /* Convert a softfloat float_relation_ (as returned by * the float*_compare functions) to the correct ARM * NZCV flag state. */ static inline uint32_t float_rel_to_flags(int res) { uint64_t flags; switch (res) { case float_relation_equal: flags = PSTATE_Z | PSTATE_C; break; case float_relation_less: flags = PSTATE_N; break; case float_relation_greater: flags = PSTATE_C; break; case float_relation_unordered: default: flags = PSTATE_C | PSTATE_V; break; } return flags; } uint64_t HELPER(vfp_cmps_a64)(float32 x, float32 y, void *fp_status) { return float_rel_to_flags(float32_compare_quiet(x, y, fp_status)); } uint64_t HELPER(vfp_cmpes_a64)(float32 x, float32 y, void *fp_status) { return float_rel_to_flags(float32_compare(x, y, fp_status)); } uint64_t HELPER(vfp_cmpd_a64)(float64 x, float64 y, void *fp_status) { return float_rel_to_flags(float64_compare_quiet(x, y, fp_status)); } uint64_t HELPER(vfp_cmped_a64)(float64 x, float64 y, void *fp_status) { return float_rel_to_flags(float64_compare(x, y, fp_status)); } float32 HELPER(vfp_mulxs)(float32 a, float32 b, void *fpstp) { float_status *fpst = fpstp; a = float32_squash_input_denormal(a, fpst); b = float32_squash_input_denormal(b, fpst); if ((float32_is_zero(a) && float32_is_infinity(b)) || (float32_is_infinity(a) && float32_is_zero(b))) { /* 2.0 with the sign bit set to sign(A) XOR sign(B) */ return make_float32((1U << 30) | ((float32_val(a) ^ float32_val(b)) & (1U << 31))); } return float32_mul(a, b, fpst); } float64 HELPER(vfp_mulxd)(float64 a, float64 b, void *fpstp) { float_status *fpst = fpstp; a = float64_squash_input_denormal(a, fpst); b = float64_squash_input_denormal(b, fpst); if ((float64_is_zero(a) && float64_is_infinity(b)) || (float64_is_infinity(a) && float64_is_zero(b))) { /* 2.0 with the sign bit set to sign(A) XOR sign(B) */ return make_float64((1ULL << 62) | ((float64_val(a) ^ float64_val(b)) & (1ULL << 63))); } return float64_mul(a, b, fpst); } uint64_t HELPER(simd_tbl)(CPUARMState *env, uint64_t result, uint64_t indices, uint32_t rn, uint32_t numregs) { /* Helper function for SIMD TBL and TBX. We have to do the table * lookup part for the 64 bits worth of indices we're passed in. * result is the initial results vector (either zeroes for TBL * or some guest values for TBX), rn the register number where * the table starts, and numregs the number of registers in the table. * We return the results of the lookups. */ int shift; for (shift = 0; shift < 64; shift += 8) { int index = extract64(indices, shift, 8); if (index < 16 * numregs) { /* Convert index (a byte offset into the virtual table * which is a series of 128-bit vectors concatenated) * into the correct register element plus a bit offset * into that element, bearing in mind that the table * can wrap around from V31 to V0. */ int elt = (rn * 2 + (index >> 3)) % 64; int bitidx = (index & 7) * 8; uint64_t *q = aa64_vfp_qreg(env, elt >> 1); uint64_t val = extract64(q[elt & 1], bitidx, 8); result = deposit64(result, shift, 8, val); } } return result; } /* 64bit/double versions of the neon float compare functions */ uint64_t HELPER(neon_ceq_f64)(float64 a, float64 b, void *fpstp) { float_status *fpst = fpstp; return -float64_eq_quiet(a, b, fpst); } uint64_t HELPER(neon_cge_f64)(float64 a, float64 b, void *fpstp) { float_status *fpst = fpstp; return -float64_le(b, a, fpst); } uint64_t HELPER(neon_cgt_f64)(float64 a, float64 b, void *fpstp) { float_status *fpst = fpstp; return -float64_lt(b, a, fpst); } /* Reciprocal step and sqrt step. Note that unlike the A32/T32 * versions, these do a fully fused multiply-add or * multiply-add-and-halve. */ #define float32_two make_float32(0x40000000) #define float32_three make_float32(0x40400000) #define float32_one_point_five make_float32(0x3fc00000) #define float64_two make_float64(0x4000000000000000ULL) #define float64_three make_float64(0x4008000000000000ULL) #define float64_one_point_five make_float64(0x3FF8000000000000ULL) float32 HELPER(recpsf_f32)(float32 a, float32 b, void *fpstp) { float_status *fpst = fpstp; a = float32_squash_input_denormal(a, fpst); b = float32_squash_input_denormal(b, fpst); a = float32_chs(a); if ((float32_is_infinity(a) && float32_is_zero(b)) || (float32_is_infinity(b) && float32_is_zero(a))) { return float32_two; } return float32_muladd(a, b, float32_two, 0, fpst); } float64 HELPER(recpsf_f64)(float64 a, float64 b, void *fpstp) { float_status *fpst = fpstp; a = float64_squash_input_denormal(a, fpst); b = float64_squash_input_denormal(b, fpst); a = float64_chs(a); if ((float64_is_infinity(a) && float64_is_zero(b)) || (float64_is_infinity(b) && float64_is_zero(a))) { return float64_two; } return float64_muladd(a, b, float64_two, 0, fpst); } float32 HELPER(rsqrtsf_f32)(float32 a, float32 b, void *fpstp) { float_status *fpst = fpstp; a = float32_squash_input_denormal(a, fpst); b = float32_squash_input_denormal(b, fpst); a = float32_chs(a); if ((float32_is_infinity(a) && float32_is_zero(b)) || (float32_is_infinity(b) && float32_is_zero(a))) { return float32_one_point_five; } return float32_muladd(a, b, float32_three, float_muladd_halve_result, fpst); } float64 HELPER(rsqrtsf_f64)(float64 a, float64 b, void *fpstp) { float_status *fpst = fpstp; a = float64_squash_input_denormal(a, fpst); b = float64_squash_input_denormal(b, fpst); a = float64_chs(a); if ((float64_is_infinity(a) && float64_is_zero(b)) || (float64_is_infinity(b) && float64_is_zero(a))) { return float64_one_point_five; } return float64_muladd(a, b, float64_three, float_muladd_halve_result, fpst); } /* Pairwise long add: add pairs of adjacent elements into * double-width elements in the result (eg _s8 is an 8x8->16 op) */ uint64_t HELPER(neon_addlp_s8)(uint64_t a) { uint64_t nsignmask = 0x0080008000800080ULL; uint64_t wsignmask = 0x8000800080008000ULL; uint64_t elementmask = 0x00ff00ff00ff00ffULL; uint64_t tmp1, tmp2; uint64_t res, signres; /* Extract odd elements, sign extend each to a 16 bit field */ tmp1 = a & elementmask; tmp1 ^= nsignmask; tmp1 |= wsignmask; tmp1 = (tmp1 - nsignmask) ^ wsignmask; /* Ditto for the even elements */ tmp2 = (a >> 8) & elementmask; tmp2 ^= nsignmask; tmp2 |= wsignmask; tmp2 = (tmp2 - nsignmask) ^ wsignmask; /* calculate the result by summing bits 0..14, 16..22, etc, * and then adjusting the sign bits 15, 23, etc manually. * This ensures the addition can't overflow the 16 bit field. */ signres = (tmp1 ^ tmp2) & wsignmask; res = (tmp1 & ~wsignmask) + (tmp2 & ~wsignmask); res ^= signres; return res; } uint64_t HELPER(neon_addlp_u8)(uint64_t a) { uint64_t tmp; tmp = a & 0x00ff00ff00ff00ffULL; tmp += (a >> 8) & 0x00ff00ff00ff00ffULL; return tmp; } uint64_t HELPER(neon_addlp_s16)(uint64_t a) { int32_t reslo, reshi; reslo = (int32_t)(int16_t)a + (int32_t)(int16_t)(a >> 16); reshi = (int32_t)(int16_t)(a >> 32) + (int32_t)(int16_t)(a >> 48); return (uint32_t)reslo | (((uint64_t)reshi) << 32); } uint64_t HELPER(neon_addlp_u16)(uint64_t a) { uint64_t tmp; tmp = a & 0x0000ffff0000ffffULL; tmp += (a >> 16) & 0x0000ffff0000ffffULL; return tmp; } /* Floating-point reciprocal exponent - see FPRecpX in ARM ARM */ float32 HELPER(frecpx_f32)(float32 a, void *fpstp) { float_status *fpst = fpstp; uint32_t val32, sbit; int32_t exp; if (float32_is_any_nan(a)) { float32 nan = a; if (float32_is_signaling_nan(a, fpst)) { float_raise(float_flag_invalid, fpst); nan = float32_maybe_silence_nan(a, fpst); } if (fpst->default_nan_mode) { nan = float32_default_nan(fpst); } return nan; } val32 = float32_val(a); sbit = 0x80000000ULL & val32; exp = extract32(val32, 23, 8); if (exp == 0) { return make_float32(sbit | (0xfe << 23)); } else { return make_float32(sbit | (~exp & 0xff) << 23); } } float64 HELPER(frecpx_f64)(float64 a, void *fpstp) { float_status *fpst = fpstp; uint64_t val64, sbit; int64_t exp; if (float64_is_any_nan(a)) { float64 nan = a; if (float64_is_signaling_nan(a, fpst)) { float_raise(float_flag_invalid, fpst); nan = float64_maybe_silence_nan(a, fpst); } if (fpst->default_nan_mode) { nan = float64_default_nan(fpst); } return nan; } val64 = float64_val(a); sbit = 0x8000000000000000ULL & val64; exp = extract64(float64_val(a), 52, 11); if (exp == 0) { return make_float64(sbit | (0x7feULL << 52)); } else { return make_float64(sbit | (~exp & 0x7ffULL) << 52); } } float32 HELPER(fcvtx_f64_to_f32)(float64 a, CPUARMState *env) { /* Von Neumann rounding is implemented by using round-to-zero * and then setting the LSB of the result if Inexact was raised. */ float32 r; float_status *fpst = &env->vfp.fp_status; float_status tstat = *fpst; int exflags; set_float_rounding_mode(float_round_to_zero, &tstat); set_float_exception_flags(0, &tstat); r = float64_to_float32(a, &tstat); r = float32_maybe_silence_nan(r, &tstat); exflags = get_float_exception_flags(&tstat); if (exflags & float_flag_inexact) { r = make_float32(float32_val(r) | 1); } exflags |= get_float_exception_flags(fpst); set_float_exception_flags(exflags, fpst); return r; } /* 64-bit versions of the CRC helpers. Note that although the operation * (and the prototypes of crc32c() and crc32() mean that only the bottom * 32 bits of the accumulator and result are used, we pass and return * uint64_t for convenience of the generated code. Unlike the 32-bit * instruction set versions, val may genuinely have 64 bits of data in it. * The upper bytes of val (above the number specified by 'bytes') must have * been zeroed out by the caller. */ uint64_t HELPER(crc32_64)(uint64_t acc, uint64_t val, uint32_t bytes) { uint8_t buf[8]; stq_le_p(buf, val); /* zlib crc32 converts the accumulator and output to one's complement. */ return crc32(acc ^ 0xffffffff, buf, bytes) ^ 0xffffffff; } uint64_t HELPER(crc32c_64)(uint64_t acc, uint64_t val, uint32_t bytes) { uint8_t buf[8]; stq_le_p(buf, val); /* Linux crc32c converts the output to one's complement. */ return crc32c(acc, buf, bytes) ^ 0xffffffff; } /* Returns 0 on success; 1 otherwise. */ static uint64_t do_paired_cmpxchg64_le(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi, bool parallel, uintptr_t ra) { Int128 oldv, cmpv, newv; bool success; cmpv = int128_make128(env->exclusive_val, env->exclusive_high); newv = int128_make128(new_lo, new_hi); if (parallel) { #ifndef CONFIG_ATOMIC128 cpu_loop_exit_atomic(ENV_GET_CPU(env), ra); #else int mem_idx = cpu_mmu_index(env, false); TCGMemOpIdx oi = make_memop_idx(MO_LEQ | MO_ALIGN_16, mem_idx); oldv = helper_atomic_cmpxchgo_le_mmu(env, addr, cmpv, newv, oi, ra); success = int128_eq(oldv, cmpv); #endif } else { uint64_t o0, o1; #ifdef CONFIG_USER_ONLY /* ??? Enforce alignment. */ uint64_t *haddr = g2h(addr); helper_retaddr = ra; o0 = ldq_le_p(haddr + 0); o1 = ldq_le_p(haddr + 1); oldv = int128_make128(o0, o1); success = int128_eq(oldv, cmpv); if (success) { stq_le_p(haddr + 0, int128_getlo(newv)); stq_le_p(haddr + 1, int128_gethi(newv)); } helper_retaddr = 0; #else int mem_idx = cpu_mmu_index(env, false); TCGMemOpIdx oi0 = make_memop_idx(MO_LEQ | MO_ALIGN_16, mem_idx); TCGMemOpIdx oi1 = make_memop_idx(MO_LEQ, mem_idx); o0 = helper_le_ldq_mmu(env, addr + 0, oi0, ra); o1 = helper_le_ldq_mmu(env, addr + 8, oi1, ra); oldv = int128_make128(o0, o1); success = int128_eq(oldv, cmpv); if (success) { helper_le_stq_mmu(env, addr + 0, int128_getlo(newv), oi1, ra); helper_le_stq_mmu(env, addr + 8, int128_gethi(newv), oi1, ra); } #endif } return !success; } uint64_t HELPER(paired_cmpxchg64_le)(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { return do_paired_cmpxchg64_le(env, addr, new_lo, new_hi, false, GETPC()); } uint64_t HELPER(paired_cmpxchg64_le_parallel)(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { return do_paired_cmpxchg64_le(env, addr, new_lo, new_hi, true, GETPC()); } static uint64_t do_paired_cmpxchg64_be(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi, bool parallel, uintptr_t ra) { Int128 oldv, cmpv, newv; bool success; /* high and low need to be switched here because this is not actually a * 128bit store but two doublewords stored consecutively */ cmpv = int128_make128(env->exclusive_high, env->exclusive_val); newv = int128_make128(new_hi, new_lo); if (parallel) { #ifndef CONFIG_ATOMIC128 cpu_loop_exit_atomic(ENV_GET_CPU(env), ra); #else int mem_idx = cpu_mmu_index(env, false); TCGMemOpIdx oi = make_memop_idx(MO_BEQ | MO_ALIGN_16, mem_idx); oldv = helper_atomic_cmpxchgo_be_mmu(env, addr, cmpv, newv, oi, ra); success = int128_eq(oldv, cmpv); #endif } else { uint64_t o0, o1; #ifdef CONFIG_USER_ONLY /* ??? Enforce alignment. */ uint64_t *haddr = g2h(addr); helper_retaddr = ra; o1 = ldq_be_p(haddr + 0); o0 = ldq_be_p(haddr + 1); oldv = int128_make128(o0, o1); success = int128_eq(oldv, cmpv); if (success) { stq_be_p(haddr + 0, int128_gethi(newv)); stq_be_p(haddr + 1, int128_getlo(newv)); } helper_retaddr = 0; #else int mem_idx = cpu_mmu_index(env, false); TCGMemOpIdx oi0 = make_memop_idx(MO_BEQ | MO_ALIGN_16, mem_idx); TCGMemOpIdx oi1 = make_memop_idx(MO_BEQ, mem_idx); o1 = helper_be_ldq_mmu(env, addr + 0, oi0, ra); o0 = helper_be_ldq_mmu(env, addr + 8, oi1, ra); oldv = int128_make128(o0, o1); success = int128_eq(oldv, cmpv); if (success) { helper_be_stq_mmu(env, addr + 0, int128_gethi(newv), oi1, ra); helper_be_stq_mmu(env, addr + 8, int128_getlo(newv), oi1, ra); } #endif } return !success; } uint64_t HELPER(paired_cmpxchg64_be)(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { return do_paired_cmpxchg64_be(env, addr, new_lo, new_hi, false, GETPC()); } uint64_t HELPER(paired_cmpxchg64_be_parallel)(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { return do_paired_cmpxchg64_be(env, addr, new_lo, new_hi, true, GETPC()); } /* * AdvSIMD half-precision */ #define ADVSIMD_HELPER(name, suffix) HELPER(glue(glue(advsimd_, name), suffix)) #define ADVSIMD_HALFOP(name) \ float16 ADVSIMD_HELPER(name, h)(float16 a, float16 b, void *fpstp) \ { \ float_status *fpst = fpstp; \ return float16_ ## name(a, b, fpst); \ } ADVSIMD_HALFOP(add) ADVSIMD_HALFOP(sub) ADVSIMD_HALFOP(mul) ADVSIMD_HALFOP(div) ADVSIMD_HALFOP(min) ADVSIMD_HALFOP(max) ADVSIMD_HALFOP(minnum) ADVSIMD_HALFOP(maxnum)