/* * 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 2.1 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 "qemu/units.h" #include "cpu.h" #include "exec/gdbstub.h" #include "exec/helper-proto.h" #include "qemu/host-utils.h" #include "qemu/log.h" #include "qemu/main-loop.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 "qemu/atomic128.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); } void HELPER(msr_i_spsel)(CPUARMState *env, uint32_t imm) { update_spsel(env, imm); } static void daif_check(CPUARMState *env, uint32_t op, uint32_t imm, uintptr_t ra) { /* DAIF update to PSTATE. This is OK from EL0 only if UMA is set. */ if (arm_current_el(env) == 0 && !(arm_sctlr(env, 0) & SCTLR_UMA)) { raise_exception_ra(env, EXCP_UDEF, syn_aa64_sysregtrap(0, extract32(op, 0, 3), extract32(op, 3, 3), 4, imm, 0x1f, 0), exception_target_el(env), ra); } } void HELPER(msr_i_daifset)(CPUARMState *env, uint32_t imm) { daif_check(env, 0x1e, imm, GETPC()); env->daif |= (imm << 6) & PSTATE_DAIF; } void HELPER(msr_i_daifclear)(CPUARMState *env, uint32_t imm) { daif_check(env, 0x1f, imm, GETPC()); env->daif &= ~((imm << 6) & PSTATE_DAIF); } /* 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_cmph_a64)(uint32_t x, uint32_t y, void *fp_status) { return float_rel_to_flags(float16_compare_quiet(x, y, fp_status)); } uint64_t HELPER(vfp_cmpeh_a64)(uint32_t x, uint32_t y, void *fp_status) { return float_rel_to_flags(float16_compare(x, y, fp_status)); } 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); } /* 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. */ uint32_t HELPER(recpsf_f16)(uint32_t a, uint32_t b, void *fpstp) { float_status *fpst = fpstp; a = float16_squash_input_denormal(a, fpst); b = float16_squash_input_denormal(b, fpst); a = float16_chs(a); if ((float16_is_infinity(a) && float16_is_zero(b)) || (float16_is_infinity(b) && float16_is_zero(a))) { return float16_two; } return float16_muladd(a, b, float16_two, 0, fpst); } 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); } uint32_t HELPER(rsqrtsf_f16)(uint32_t a, uint32_t b, void *fpstp) { float_status *fpst = fpstp; a = float16_squash_input_denormal(a, fpst); b = float16_squash_input_denormal(b, fpst); a = float16_chs(a); if ((float16_is_infinity(a) && float16_is_zero(b)) || (float16_is_infinity(b) && float16_is_zero(a))) { return float16_one_point_five; } return float16_muladd(a, b, float16_three, float_muladd_halve_result, 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 */ uint32_t HELPER(frecpx_f16)(uint32_t a, void *fpstp) { float_status *fpst = fpstp; uint16_t val16, sbit; int16_t exp; if (float16_is_any_nan(a)) { float16 nan = a; if (float16_is_signaling_nan(a, fpst)) { float_raise(float_flag_invalid, fpst); if (!fpst->default_nan_mode) { nan = float16_silence_nan(a, fpst); } } if (fpst->default_nan_mode) { nan = float16_default_nan(fpst); } return nan; } a = float16_squash_input_denormal(a, fpst); val16 = float16_val(a); sbit = 0x8000 & val16; exp = extract32(val16, 10, 5); if (exp == 0) { return make_float16(deposit32(sbit, 10, 5, 0x1e)); } else { return make_float16(deposit32(sbit, 10, 5, ~exp)); } } 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); if (!fpst->default_nan_mode) { nan = float32_silence_nan(a, fpst); } } if (fpst->default_nan_mode) { nan = float32_default_nan(fpst); } return nan; } a = float32_squash_input_denormal(a, fpst); 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); if (!fpst->default_nan_mode) { nan = float64_silence_nan(a, fpst); } } if (fpst->default_nan_mode) { nan = float64_default_nan(fpst); } return nan; } a = float64_squash_input_denormal(a, fpst); 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); 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; } uint64_t HELPER(paired_cmpxchg64_le)(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { Int128 cmpv = int128_make128(env->exclusive_val, env->exclusive_high); Int128 newv = int128_make128(new_lo, new_hi); Int128 oldv; uintptr_t ra = GETPC(); uint64_t o0, o1; bool success; #ifdef CONFIG_USER_ONLY /* ??? Enforce alignment. */ uint64_t *haddr = g2h(env_cpu(env), addr); set_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)); } clear_helper_retaddr(); #else int mem_idx = cpu_mmu_index(env, false); MemOpIdx oi0 = make_memop_idx(MO_LEQ | MO_ALIGN_16, mem_idx); MemOpIdx 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_parallel)(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { Int128 oldv, cmpv, newv; uintptr_t ra = GETPC(); bool success; int mem_idx; MemOpIdx oi; assert(HAVE_CMPXCHG128); mem_idx = cpu_mmu_index(env, false); oi = make_memop_idx(MO_LE | MO_128 | MO_ALIGN, mem_idx); cmpv = int128_make128(env->exclusive_val, env->exclusive_high); newv = int128_make128(new_lo, new_hi); oldv = cpu_atomic_cmpxchgo_le_mmu(env, addr, cmpv, newv, oi, ra); success = int128_eq(oldv, cmpv); return !success; } uint64_t HELPER(paired_cmpxchg64_be)(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { /* * High and low need to be switched here because this is not actually a * 128bit store but two doublewords stored consecutively */ Int128 cmpv = int128_make128(env->exclusive_high, env->exclusive_val); Int128 newv = int128_make128(new_hi, new_lo); Int128 oldv; uintptr_t ra = GETPC(); uint64_t o0, o1; bool success; #ifdef CONFIG_USER_ONLY /* ??? Enforce alignment. */ uint64_t *haddr = g2h(env_cpu(env), addr); set_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)); } clear_helper_retaddr(); #else int mem_idx = cpu_mmu_index(env, false); MemOpIdx oi0 = make_memop_idx(MO_BEQ | MO_ALIGN_16, mem_idx); MemOpIdx 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_parallel)(CPUARMState *env, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { Int128 oldv, cmpv, newv; uintptr_t ra = GETPC(); bool success; int mem_idx; MemOpIdx oi; assert(HAVE_CMPXCHG128); mem_idx = cpu_mmu_index(env, false); oi = make_memop_idx(MO_BE | MO_128 | MO_ALIGN, mem_idx); /* * 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); oldv = cpu_atomic_cmpxchgo_be_mmu(env, addr, cmpv, newv, oi, ra); success = int128_eq(oldv, cmpv); return !success; } /* Writes back the old data into Rs. */ void HELPER(casp_le_parallel)(CPUARMState *env, uint32_t rs, uint64_t addr, uint64_t new_lo, uint64_t new_hi) { Int128 oldv, cmpv, newv; uintptr_t ra = GETPC(); int mem_idx; MemOpIdx oi; assert(HAVE_CMPXCHG128); mem_idx = cpu_mmu_index(env, false); oi = make_memop_idx(MO_LE | MO_128 | MO_ALIGN, mem_idx); cmpv = int128_make128(env->xregs[rs], env->xregs[rs + 1]); newv = int128_make128(new_lo, new_hi); oldv = cpu_atomic_cmpxchgo_le_mmu(env, addr, cmpv, newv, oi, ra); env->xregs[rs] = int128_getlo(oldv); env->xregs[rs + 1] = int128_gethi(oldv); } void HELPER(casp_be_parallel)(CPUARMState *env, uint32_t rs, uint64_t addr, uint64_t new_hi, uint64_t new_lo) { Int128 oldv, cmpv, newv; uintptr_t ra = GETPC(); int mem_idx; MemOpIdx oi; assert(HAVE_CMPXCHG128); mem_idx = cpu_mmu_index(env, false); oi = make_memop_idx(MO_LE | MO_128 | MO_ALIGN, mem_idx); cmpv = int128_make128(env->xregs[rs + 1], env->xregs[rs]); newv = int128_make128(new_lo, new_hi); oldv = cpu_atomic_cmpxchgo_be_mmu(env, addr, cmpv, newv, oi, ra); env->xregs[rs + 1] = int128_getlo(oldv); env->xregs[rs] = int128_gethi(oldv); } /* * AdvSIMD half-precision */ #define ADVSIMD_HELPER(name, suffix) HELPER(glue(glue(advsimd_, name), suffix)) #define ADVSIMD_HALFOP(name) \ uint32_t ADVSIMD_HELPER(name, h)(uint32_t a, uint32_t 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) #define ADVSIMD_TWOHALFOP(name) \ uint32_t ADVSIMD_HELPER(name, 2h)(uint32_t two_a, uint32_t two_b, void *fpstp) \ { \ float16 a1, a2, b1, b2; \ uint32_t r1, r2; \ float_status *fpst = fpstp; \ a1 = extract32(two_a, 0, 16); \ a2 = extract32(two_a, 16, 16); \ b1 = extract32(two_b, 0, 16); \ b2 = extract32(two_b, 16, 16); \ r1 = float16_ ## name(a1, b1, fpst); \ r2 = float16_ ## name(a2, b2, fpst); \ return deposit32(r1, 16, 16, r2); \ } ADVSIMD_TWOHALFOP(add) ADVSIMD_TWOHALFOP(sub) ADVSIMD_TWOHALFOP(mul) ADVSIMD_TWOHALFOP(div) ADVSIMD_TWOHALFOP(min) ADVSIMD_TWOHALFOP(max) ADVSIMD_TWOHALFOP(minnum) ADVSIMD_TWOHALFOP(maxnum) /* Data processing - scalar floating-point and advanced SIMD */ static float16 float16_mulx(float16 a, float16 b, void *fpstp) { float_status *fpst = fpstp; a = float16_squash_input_denormal(a, fpst); b = float16_squash_input_denormal(b, fpst); if ((float16_is_zero(a) && float16_is_infinity(b)) || (float16_is_infinity(a) && float16_is_zero(b))) { /* 2.0 with the sign bit set to sign(A) XOR sign(B) */ return make_float16((1U << 14) | ((float16_val(a) ^ float16_val(b)) & (1U << 15))); } return float16_mul(a, b, fpst); } ADVSIMD_HALFOP(mulx) ADVSIMD_TWOHALFOP(mulx) /* fused multiply-accumulate */ uint32_t HELPER(advsimd_muladdh)(uint32_t a, uint32_t b, uint32_t c, void *fpstp) { float_status *fpst = fpstp; return float16_muladd(a, b, c, 0, fpst); } uint32_t HELPER(advsimd_muladd2h)(uint32_t two_a, uint32_t two_b, uint32_t two_c, void *fpstp) { float_status *fpst = fpstp; float16 a1, a2, b1, b2, c1, c2; uint32_t r1, r2; a1 = extract32(two_a, 0, 16); a2 = extract32(two_a, 16, 16); b1 = extract32(two_b, 0, 16); b2 = extract32(two_b, 16, 16); c1 = extract32(two_c, 0, 16); c2 = extract32(two_c, 16, 16); r1 = float16_muladd(a1, b1, c1, 0, fpst); r2 = float16_muladd(a2, b2, c2, 0, fpst); return deposit32(r1, 16, 16, r2); } /* * Floating point comparisons produce an integer result. Softfloat * routines return float_relation types which we convert to the 0/-1 * Neon requires. */ #define ADVSIMD_CMPRES(test) (test) ? 0xffff : 0 uint32_t HELPER(advsimd_ceq_f16)(uint32_t a, uint32_t b, void *fpstp) { float_status *fpst = fpstp; int compare = float16_compare_quiet(a, b, fpst); return ADVSIMD_CMPRES(compare == float_relation_equal); } uint32_t HELPER(advsimd_cge_f16)(uint32_t a, uint32_t b, void *fpstp) { float_status *fpst = fpstp; int compare = float16_compare(a, b, fpst); return ADVSIMD_CMPRES(compare == float_relation_greater || compare == float_relation_equal); } uint32_t HELPER(advsimd_cgt_f16)(uint32_t a, uint32_t b, void *fpstp) { float_status *fpst = fpstp; int compare = float16_compare(a, b, fpst); return ADVSIMD_CMPRES(compare == float_relation_greater); } uint32_t HELPER(advsimd_acge_f16)(uint32_t a, uint32_t b, void *fpstp) { float_status *fpst = fpstp; float16 f0 = float16_abs(a); float16 f1 = float16_abs(b); int compare = float16_compare(f0, f1, fpst); return ADVSIMD_CMPRES(compare == float_relation_greater || compare == float_relation_equal); } uint32_t HELPER(advsimd_acgt_f16)(uint32_t a, uint32_t b, void *fpstp) { float_status *fpst = fpstp; float16 f0 = float16_abs(a); float16 f1 = float16_abs(b); int compare = float16_compare(f0, f1, fpst); return ADVSIMD_CMPRES(compare == float_relation_greater); } /* round to integral */ uint32_t HELPER(advsimd_rinth_exact)(uint32_t x, void *fp_status) { return float16_round_to_int(x, fp_status); } uint32_t HELPER(advsimd_rinth)(uint32_t x, void *fp_status) { int old_flags = get_float_exception_flags(fp_status), new_flags; float16 ret; ret = float16_round_to_int(x, fp_status); /* Suppress any inexact exceptions the conversion produced */ if (!(old_flags & float_flag_inexact)) { new_flags = get_float_exception_flags(fp_status); set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status); } return ret; } /* * Half-precision floating point conversion functions * * There are a multitude of conversion functions with various * different rounding modes. This is dealt with by the calling code * setting the mode appropriately before calling the helper. */ uint32_t HELPER(advsimd_f16tosinth)(uint32_t a, void *fpstp) { float_status *fpst = fpstp; /* Invalid if we are passed a NaN */ if (float16_is_any_nan(a)) { float_raise(float_flag_invalid, fpst); return 0; } return float16_to_int16(a, fpst); } uint32_t HELPER(advsimd_f16touinth)(uint32_t a, void *fpstp) { float_status *fpst = fpstp; /* Invalid if we are passed a NaN */ if (float16_is_any_nan(a)) { float_raise(float_flag_invalid, fpst); return 0; } return float16_to_uint16(a, fpst); } static int el_from_spsr(uint32_t spsr) { /* Return the exception level that this SPSR is requesting a return to, * or -1 if it is invalid (an illegal return) */ if (spsr & PSTATE_nRW) { switch (spsr & CPSR_M) { case ARM_CPU_MODE_USR: return 0; case ARM_CPU_MODE_HYP: return 2; case ARM_CPU_MODE_FIQ: case ARM_CPU_MODE_IRQ: case ARM_CPU_MODE_SVC: case ARM_CPU_MODE_ABT: case ARM_CPU_MODE_UND: case ARM_CPU_MODE_SYS: return 1; case ARM_CPU_MODE_MON: /* Returning to Mon from AArch64 is never possible, * so this is an illegal return. */ default: return -1; } } else { if (extract32(spsr, 1, 1)) { /* Return with reserved M[1] bit set */ return -1; } if (extract32(spsr, 0, 4) == 1) { /* return to EL0 with M[0] bit set */ return -1; } return extract32(spsr, 2, 2); } } static void cpsr_write_from_spsr_elx(CPUARMState *env, uint32_t val) { uint32_t mask; /* Save SPSR_ELx.SS into PSTATE. */ env->pstate = (env->pstate & ~PSTATE_SS) | (val & PSTATE_SS); val &= ~PSTATE_SS; /* Move DIT to the correct location for CPSR */ if (val & PSTATE_DIT) { val &= ~PSTATE_DIT; val |= CPSR_DIT; } mask = aarch32_cpsr_valid_mask(env->features, \ &env_archcpu(env)->isar); cpsr_write(env, val, mask, CPSRWriteRaw); } void HELPER(exception_return)(CPUARMState *env, uint64_t new_pc) { int cur_el = arm_current_el(env); unsigned int spsr_idx = aarch64_banked_spsr_index(cur_el); uint32_t spsr = env->banked_spsr[spsr_idx]; int new_el; bool return_to_aa64 = (spsr & PSTATE_nRW) == 0; aarch64_save_sp(env, cur_el); arm_clear_exclusive(env); /* We must squash the PSTATE.SS bit to zero unless both of the * following hold: * 1. debug exceptions are currently disabled * 2. singlestep will be active in the EL we return to * We check 1 here and 2 after we've done the pstate/cpsr write() to * transition to the EL we're going to. */ if (arm_generate_debug_exceptions(env)) { spsr &= ~PSTATE_SS; } new_el = el_from_spsr(spsr); if (new_el == -1) { goto illegal_return; } if (new_el > cur_el || (new_el == 2 && !arm_is_el2_enabled(env))) { /* Disallow return to an EL which is unimplemented or higher * than the current one. */ goto illegal_return; } if (new_el != 0 && arm_el_is_aa64(env, new_el) != return_to_aa64) { /* Return to an EL which is configured for a different register width */ goto illegal_return; } if (new_el == 1 && (arm_hcr_el2_eff(env) & HCR_TGE)) { goto illegal_return; } qemu_mutex_lock_iothread(); arm_call_pre_el_change_hook(env_archcpu(env)); qemu_mutex_unlock_iothread(); if (!return_to_aa64) { env->aarch64 = 0; /* We do a raw CPSR write because aarch64_sync_64_to_32() * will sort the register banks out for us, and we've already * caught all the bad-mode cases in el_from_spsr(). */ cpsr_write_from_spsr_elx(env, spsr); if (!arm_singlestep_active(env)) { env->pstate &= ~PSTATE_SS; } aarch64_sync_64_to_32(env); if (spsr & CPSR_T) { env->regs[15] = new_pc & ~0x1; } else { env->regs[15] = new_pc & ~0x3; } helper_rebuild_hflags_a32(env, new_el); qemu_log_mask(CPU_LOG_INT, "Exception return from AArch64 EL%d to " "AArch32 EL%d PC 0x%" PRIx32 "\n", cur_el, new_el, env->regs[15]); } else { int tbii; env->aarch64 = 1; spsr &= aarch64_pstate_valid_mask(&env_archcpu(env)->isar); pstate_write(env, spsr); if (!arm_singlestep_active(env)) { env->pstate &= ~PSTATE_SS; } aarch64_restore_sp(env, new_el); helper_rebuild_hflags_a64(env, new_el); /* * Apply TBI to the exception return address. We had to delay this * until after we selected the new EL, so that we could select the * correct TBI+TBID bits. This is made easier by waiting until after * the hflags rebuild, since we can pull the composite TBII field * from there. */ tbii = EX_TBFLAG_A64(env->hflags, TBII); if ((tbii >> extract64(new_pc, 55, 1)) & 1) { /* TBI is enabled. */ int core_mmu_idx = cpu_mmu_index(env, false); if (regime_has_2_ranges(core_to_aa64_mmu_idx(core_mmu_idx))) { new_pc = sextract64(new_pc, 0, 56); } else { new_pc = extract64(new_pc, 0, 56); } } env->pc = new_pc; qemu_log_mask(CPU_LOG_INT, "Exception return from AArch64 EL%d to " "AArch64 EL%d PC 0x%" PRIx64 "\n", cur_el, new_el, env->pc); } /* * Note that cur_el can never be 0. If new_el is 0, then * el0_a64 is return_to_aa64, else el0_a64 is ignored. */ aarch64_sve_change_el(env, cur_el, new_el, return_to_aa64); qemu_mutex_lock_iothread(); arm_call_el_change_hook(env_archcpu(env)); qemu_mutex_unlock_iothread(); return; illegal_return: /* Illegal return events of various kinds have architecturally * mandated behaviour: * restore NZCV and DAIF from SPSR_ELx * set PSTATE.IL * restore PC from ELR_ELx * no change to exception level, execution state or stack pointer */ env->pstate |= PSTATE_IL; env->pc = new_pc; spsr &= PSTATE_NZCV | PSTATE_DAIF; spsr |= pstate_read(env) & ~(PSTATE_NZCV | PSTATE_DAIF); pstate_write(env, spsr); if (!arm_singlestep_active(env)) { env->pstate &= ~PSTATE_SS; } helper_rebuild_hflags_a64(env, cur_el); qemu_log_mask(LOG_GUEST_ERROR, "Illegal exception return at EL%d: " "resuming execution at 0x%" PRIx64 "\n", cur_el, env->pc); } /* * Square Root and Reciprocal square root */ uint32_t HELPER(sqrt_f16)(uint32_t a, void *fpstp) { float_status *s = fpstp; return float16_sqrt(a, s); } void HELPER(dc_zva)(CPUARMState *env, uint64_t vaddr_in) { /* * Implement DC ZVA, which zeroes a fixed-length block of memory. * Note that we do not implement the (architecturally mandated) * alignment fault for attempts to use this on Device memory * (which matches the usual QEMU behaviour of not implementing either * alignment faults or any memory attribute handling). */ int blocklen = 4 << env_archcpu(env)->dcz_blocksize; uint64_t vaddr = vaddr_in & ~(blocklen - 1); int mmu_idx = cpu_mmu_index(env, false); void *mem; /* * Trapless lookup. In addition to actual invalid page, may * return NULL for I/O, watchpoints, clean pages, etc. */ mem = tlb_vaddr_to_host(env, vaddr, MMU_DATA_STORE, mmu_idx); #ifndef CONFIG_USER_ONLY if (unlikely(!mem)) { uintptr_t ra = GETPC(); /* * Trap if accessing an invalid page. DC_ZVA requires that we supply * the original pointer for an invalid page. But watchpoints require * that we probe the actual space. So do both. */ (void) probe_write(env, vaddr_in, 1, mmu_idx, ra); mem = probe_write(env, vaddr, blocklen, mmu_idx, ra); if (unlikely(!mem)) { /* * The only remaining reason for mem == NULL is I/O. * Just do a series of byte writes as the architecture demands. */ for (int i = 0; i < blocklen; i++) { cpu_stb_mmuidx_ra(env, vaddr + i, 0, mmu_idx, ra); } return; } } #endif memset(mem, 0, blocklen); }