diff options
Diffstat (limited to 'target/arm/tcg/translate-m-nocp.c')
| -rw-r--r-- | target/arm/tcg/translate-m-nocp.c | 788 |
1 files changed, 788 insertions, 0 deletions
diff --git a/target/arm/tcg/translate-m-nocp.c b/target/arm/tcg/translate-m-nocp.c new file mode 100644 index 0000000..5df7d46 --- /dev/null +++ b/target/arm/tcg/translate-m-nocp.c @@ -0,0 +1,788 @@ +/* + * ARM translation: M-profile NOCP special-case instructions + * + * Copyright (c) 2020 Linaro, Ltd. + * + * 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 <http://www.gnu.org/licenses/>. + */ + +#include "qemu/osdep.h" +#include "tcg/tcg-op.h" +#include "tcg/tcg-op-gvec.h" +#include "translate.h" +#include "translate-a32.h" + +#include "decode-m-nocp.c.inc" + +/* + * Decode VLLDM and VLSTM are nonstandard because: + * * if there is no FPU then these insns must NOP in + * Secure state and UNDEF in Nonsecure state + * * if there is an FPU then these insns do not have + * the usual behaviour that vfp_access_check() provides of + * being controlled by CPACR/NSACR enable bits or the + * lazy-stacking logic. + */ +static bool trans_VLLDM_VLSTM(DisasContext *s, arg_VLLDM_VLSTM *a) +{ + TCGv_i32 fptr; + + if (!arm_dc_feature(s, ARM_FEATURE_M) || + !arm_dc_feature(s, ARM_FEATURE_V8)) { + return false; + } + + if (a->op) { + /* + * T2 encoding ({D0-D31} reglist): v8.1M and up. We choose not + * to take the IMPDEF option to make memory accesses to the stack + * slots that correspond to the D16-D31 registers (discarding + * read data and writing UNKNOWN values), so for us the T2 + * encoding behaves identically to the T1 encoding. + */ + if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { + return false; + } + } else { + /* + * T1 encoding ({D0-D15} reglist); undef if we have 32 Dregs. + * This is currently architecturally impossible, but we add the + * check to stay in line with the pseudocode. Note that we must + * emit code for the UNDEF so it takes precedence over the NOCP. + */ + if (dc_isar_feature(aa32_simd_r32, s)) { + unallocated_encoding(s); + return true; + } + } + + /* + * If not secure, UNDEF. We must emit code for this + * rather than returning false so that this takes + * precedence over the m-nocp.decode NOCP fallback. + */ + if (!s->v8m_secure) { + unallocated_encoding(s); + return true; + } + + s->eci_handled = true; + + /* If no fpu, NOP. */ + if (!dc_isar_feature(aa32_vfp, s)) { + clear_eci_state(s); + return true; + } + + fptr = load_reg(s, a->rn); + if (a->l) { + gen_helper_v7m_vlldm(cpu_env, fptr); + } else { + gen_helper_v7m_vlstm(cpu_env, fptr); + } + tcg_temp_free_i32(fptr); + + clear_eci_state(s); + + /* + * End the TB, because we have updated FP control bits, + * and possibly VPR or LTPSIZE. + */ + s->base.is_jmp = DISAS_UPDATE_EXIT; + return true; +} + +static bool trans_VSCCLRM(DisasContext *s, arg_VSCCLRM *a) +{ + int btmreg, topreg; + TCGv_i64 zero; + TCGv_i32 aspen, sfpa; + + if (!dc_isar_feature(aa32_m_sec_state, s)) { + /* Before v8.1M, fall through in decode to NOCP check */ + return false; + } + + /* Explicitly UNDEF because this takes precedence over NOCP */ + if (!arm_dc_feature(s, ARM_FEATURE_M_MAIN) || !s->v8m_secure) { + unallocated_encoding(s); + return true; + } + + s->eci_handled = true; + + if (!dc_isar_feature(aa32_vfp_simd, s)) { + /* NOP if we have neither FP nor MVE */ + clear_eci_state(s); + return true; + } + + /* + * If FPCCR.ASPEN != 0 && CONTROL_S.SFPA == 0 then there is no + * active floating point context so we must NOP (without doing + * any lazy state preservation or the NOCP check). + */ + aspen = load_cpu_field(v7m.fpccr[M_REG_S]); + sfpa = load_cpu_field(v7m.control[M_REG_S]); + tcg_gen_andi_i32(aspen, aspen, R_V7M_FPCCR_ASPEN_MASK); + tcg_gen_xori_i32(aspen, aspen, R_V7M_FPCCR_ASPEN_MASK); + tcg_gen_andi_i32(sfpa, sfpa, R_V7M_CONTROL_SFPA_MASK); + tcg_gen_or_i32(sfpa, sfpa, aspen); + arm_gen_condlabel(s); + tcg_gen_brcondi_i32(TCG_COND_EQ, sfpa, 0, s->condlabel.label); + + if (s->fp_excp_el != 0) { + gen_exception_insn_el(s, 0, EXCP_NOCP, + syn_uncategorized(), s->fp_excp_el); + return true; + } + + topreg = a->vd + a->imm - 1; + btmreg = a->vd; + + /* Convert to Sreg numbers if the insn specified in Dregs */ + if (a->size == 3) { + topreg = topreg * 2 + 1; + btmreg *= 2; + } + + if (topreg > 63 || (topreg > 31 && !(topreg & 1))) { + /* UNPREDICTABLE: we choose to undef */ + unallocated_encoding(s); + return true; + } + + /* Silently ignore requests to clear D16-D31 if they don't exist */ + if (topreg > 31 && !dc_isar_feature(aa32_simd_r32, s)) { + topreg = 31; + } + + if (!vfp_access_check(s)) { + return true; + } + + /* Zero the Sregs from btmreg to topreg inclusive. */ + zero = tcg_constant_i64(0); + if (btmreg & 1) { + write_neon_element64(zero, btmreg >> 1, 1, MO_32); + btmreg++; + } + for (; btmreg + 1 <= topreg; btmreg += 2) { + write_neon_element64(zero, btmreg >> 1, 0, MO_64); + } + if (btmreg == topreg) { + write_neon_element64(zero, btmreg >> 1, 0, MO_32); + btmreg++; + } + assert(btmreg == topreg + 1); + if (dc_isar_feature(aa32_mve, s)) { + store_cpu_field(tcg_constant_i32(0), v7m.vpr); + } + + clear_eci_state(s); + return true; +} + +/* + * M-profile provides two different sets of instructions that can + * access floating point system registers: VMSR/VMRS (which move + * to/from a general purpose register) and VLDR/VSTR sysreg (which + * move directly to/from memory). In some cases there are also side + * effects which must happen after any write to memory (which could + * cause an exception). So we implement the common logic for the + * sysreg access in gen_M_fp_sysreg_write() and gen_M_fp_sysreg_read(), + * which take pointers to callback functions which will perform the + * actual "read/write general purpose register" and "read/write + * memory" operations. + */ + +/* + * Emit code to store the sysreg to its final destination; frees the + * TCG temp 'value' it is passed. do_access is true to do the store, + * and false to skip it and only perform side-effects like base + * register writeback. + */ +typedef void fp_sysreg_storefn(DisasContext *s, void *opaque, TCGv_i32 value, + bool do_access); +/* + * Emit code to load the value to be copied to the sysreg; returns + * a new TCG temporary. do_access is true to do the store, + * and false to skip it and only perform side-effects like base + * register writeback. + */ +typedef TCGv_i32 fp_sysreg_loadfn(DisasContext *s, void *opaque, + bool do_access); + +/* Common decode/access checks for fp sysreg read/write */ +typedef enum FPSysRegCheckResult { + FPSysRegCheckFailed, /* caller should return false */ + FPSysRegCheckDone, /* caller should return true */ + FPSysRegCheckContinue, /* caller should continue generating code */ +} FPSysRegCheckResult; + +static FPSysRegCheckResult fp_sysreg_checks(DisasContext *s, int regno) +{ + if (!dc_isar_feature(aa32_fpsp_v2, s) && !dc_isar_feature(aa32_mve, s)) { + return FPSysRegCheckFailed; + } + + switch (regno) { + case ARM_VFP_FPSCR: + case QEMU_VFP_FPSCR_NZCV: + break; + case ARM_VFP_FPSCR_NZCVQC: + if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { + return FPSysRegCheckFailed; + } + break; + case ARM_VFP_FPCXT_S: + case ARM_VFP_FPCXT_NS: + if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { + return FPSysRegCheckFailed; + } + if (!s->v8m_secure) { + return FPSysRegCheckFailed; + } + break; + case ARM_VFP_VPR: + case ARM_VFP_P0: + if (!dc_isar_feature(aa32_mve, s)) { + return FPSysRegCheckFailed; + } + break; + default: + return FPSysRegCheckFailed; + } + + /* + * FPCXT_NS is a special case: it has specific handling for + * "current FP state is inactive", and must do the PreserveFPState() + * but not the usual full set of actions done by ExecuteFPCheck(). + * So we don't call vfp_access_check() and the callers must handle this. + */ + if (regno != ARM_VFP_FPCXT_NS && !vfp_access_check(s)) { + return FPSysRegCheckDone; + } + return FPSysRegCheckContinue; +} + +static void gen_branch_fpInactive(DisasContext *s, TCGCond cond, + TCGLabel *label) +{ + /* + * FPCXT_NS is a special case: it has specific handling for + * "current FP state is inactive", and must do the PreserveFPState() + * but not the usual full set of actions done by ExecuteFPCheck(). + * We don't have a TB flag that matches the fpInactive check, so we + * do it at runtime as we don't expect FPCXT_NS accesses to be frequent. + * + * Emit code that checks fpInactive and does a conditional + * branch to label based on it: + * if cond is TCG_COND_NE then branch if fpInactive != 0 (ie if inactive) + * if cond is TCG_COND_EQ then branch if fpInactive == 0 (ie if active) + */ + assert(cond == TCG_COND_EQ || cond == TCG_COND_NE); + + /* fpInactive = FPCCR_NS.ASPEN == 1 && CONTROL.FPCA == 0 */ + TCGv_i32 aspen, fpca; + aspen = load_cpu_field(v7m.fpccr[M_REG_NS]); + fpca = load_cpu_field(v7m.control[M_REG_S]); + tcg_gen_andi_i32(aspen, aspen, R_V7M_FPCCR_ASPEN_MASK); + tcg_gen_xori_i32(aspen, aspen, R_V7M_FPCCR_ASPEN_MASK); + tcg_gen_andi_i32(fpca, fpca, R_V7M_CONTROL_FPCA_MASK); + tcg_gen_or_i32(fpca, fpca, aspen); + tcg_gen_brcondi_i32(tcg_invert_cond(cond), fpca, 0, label); + tcg_temp_free_i32(aspen); + tcg_temp_free_i32(fpca); +} + +static bool gen_M_fp_sysreg_write(DisasContext *s, int regno, + fp_sysreg_loadfn *loadfn, + void *opaque) +{ + /* Do a write to an M-profile floating point system register */ + TCGv_i32 tmp; + TCGLabel *lab_end = NULL; + + switch (fp_sysreg_checks(s, regno)) { + case FPSysRegCheckFailed: + return false; + case FPSysRegCheckDone: + return true; + case FPSysRegCheckContinue: + break; + } + + switch (regno) { + case ARM_VFP_FPSCR: + tmp = loadfn(s, opaque, true); + gen_helper_vfp_set_fpscr(cpu_env, tmp); + tcg_temp_free_i32(tmp); + gen_lookup_tb(s); + break; + case ARM_VFP_FPSCR_NZCVQC: + { + TCGv_i32 fpscr; + tmp = loadfn(s, opaque, true); + if (dc_isar_feature(aa32_mve, s)) { + /* QC is only present for MVE; otherwise RES0 */ + TCGv_i32 qc = tcg_temp_new_i32(); + tcg_gen_andi_i32(qc, tmp, FPCR_QC); + /* + * The 4 vfp.qc[] fields need only be "zero" vs "non-zero"; + * here writing the same value into all elements is simplest. + */ + tcg_gen_gvec_dup_i32(MO_32, offsetof(CPUARMState, vfp.qc), + 16, 16, qc); + } + tcg_gen_andi_i32(tmp, tmp, FPCR_NZCV_MASK); + fpscr = load_cpu_field(vfp.xregs[ARM_VFP_FPSCR]); + tcg_gen_andi_i32(fpscr, fpscr, ~FPCR_NZCV_MASK); + tcg_gen_or_i32(fpscr, fpscr, tmp); + store_cpu_field(fpscr, vfp.xregs[ARM_VFP_FPSCR]); + tcg_temp_free_i32(tmp); + break; + } + case ARM_VFP_FPCXT_NS: + { + TCGLabel *lab_active = gen_new_label(); + + lab_end = gen_new_label(); + gen_branch_fpInactive(s, TCG_COND_EQ, lab_active); + /* + * fpInactive case: write is a NOP, so only do side effects + * like register writeback before we branch to end + */ + loadfn(s, opaque, false); + tcg_gen_br(lab_end); + + gen_set_label(lab_active); + /* + * !fpInactive: if FPU disabled, take NOCP exception; + * otherwise PreserveFPState(), and then FPCXT_NS writes + * behave the same as FPCXT_S writes. + */ + if (!vfp_access_check_m(s, true)) { + /* + * This was only a conditional exception, so override + * gen_exception_insn_el()'s default to DISAS_NORETURN + */ + s->base.is_jmp = DISAS_NEXT; + break; + } + } + /* fall through */ + case ARM_VFP_FPCXT_S: + { + TCGv_i32 sfpa, control; + /* + * Set FPSCR and CONTROL.SFPA from value; the new FPSCR takes + * bits [27:0] from value and zeroes bits [31:28]. + */ + tmp = loadfn(s, opaque, true); + sfpa = tcg_temp_new_i32(); + tcg_gen_shri_i32(sfpa, tmp, 31); + control = load_cpu_field(v7m.control[M_REG_S]); + tcg_gen_deposit_i32(control, control, sfpa, + R_V7M_CONTROL_SFPA_SHIFT, 1); + store_cpu_field(control, v7m.control[M_REG_S]); + tcg_gen_andi_i32(tmp, tmp, ~FPCR_NZCV_MASK); + gen_helper_vfp_set_fpscr(cpu_env, tmp); + s->base.is_jmp = DISAS_UPDATE_NOCHAIN; + tcg_temp_free_i32(tmp); + tcg_temp_free_i32(sfpa); + break; + } + case ARM_VFP_VPR: + /* Behaves as NOP if not privileged */ + if (IS_USER(s)) { + loadfn(s, opaque, false); + break; + } + tmp = loadfn(s, opaque, true); + store_cpu_field(tmp, v7m.vpr); + s->base.is_jmp = DISAS_UPDATE_NOCHAIN; + break; + case ARM_VFP_P0: + { + TCGv_i32 vpr; + tmp = loadfn(s, opaque, true); + vpr = load_cpu_field(v7m.vpr); + tcg_gen_deposit_i32(vpr, vpr, tmp, + R_V7M_VPR_P0_SHIFT, R_V7M_VPR_P0_LENGTH); + store_cpu_field(vpr, v7m.vpr); + s->base.is_jmp = DISAS_UPDATE_NOCHAIN; + tcg_temp_free_i32(tmp); + break; + } + default: + g_assert_not_reached(); + } + if (lab_end) { + gen_set_label(lab_end); + } + return true; +} + +static bool gen_M_fp_sysreg_read(DisasContext *s, int regno, + fp_sysreg_storefn *storefn, + void *opaque) +{ + /* Do a read from an M-profile floating point system register */ + TCGv_i32 tmp; + TCGLabel *lab_end = NULL; + bool lookup_tb = false; + + switch (fp_sysreg_checks(s, regno)) { + case FPSysRegCheckFailed: + return false; + case FPSysRegCheckDone: + return true; + case FPSysRegCheckContinue: + break; + } + + if (regno == ARM_VFP_FPSCR_NZCVQC && !dc_isar_feature(aa32_mve, s)) { + /* QC is RES0 without MVE, so NZCVQC simplifies to NZCV */ + regno = QEMU_VFP_FPSCR_NZCV; + } + + switch (regno) { + case ARM_VFP_FPSCR: + tmp = tcg_temp_new_i32(); + gen_helper_vfp_get_fpscr(tmp, cpu_env); + storefn(s, opaque, tmp, true); + break; + case ARM_VFP_FPSCR_NZCVQC: + tmp = tcg_temp_new_i32(); + gen_helper_vfp_get_fpscr(tmp, cpu_env); + tcg_gen_andi_i32(tmp, tmp, FPCR_NZCVQC_MASK); + storefn(s, opaque, tmp, true); + break; + case QEMU_VFP_FPSCR_NZCV: + /* + * Read just NZCV; this is a special case to avoid the + * helper call for the "VMRS to CPSR.NZCV" insn. + */ + tmp = load_cpu_field(vfp.xregs[ARM_VFP_FPSCR]); + tcg_gen_andi_i32(tmp, tmp, FPCR_NZCV_MASK); + storefn(s, opaque, tmp, true); + break; + case ARM_VFP_FPCXT_S: + { + TCGv_i32 control, sfpa, fpscr; + /* Bits [27:0] from FPSCR, bit [31] from CONTROL.SFPA */ + tmp = tcg_temp_new_i32(); + sfpa = tcg_temp_new_i32(); + gen_helper_vfp_get_fpscr(tmp, cpu_env); + tcg_gen_andi_i32(tmp, tmp, ~FPCR_NZCV_MASK); + control = load_cpu_field(v7m.control[M_REG_S]); + tcg_gen_andi_i32(sfpa, control, R_V7M_CONTROL_SFPA_MASK); + tcg_gen_shli_i32(sfpa, sfpa, 31 - R_V7M_CONTROL_SFPA_SHIFT); + tcg_gen_or_i32(tmp, tmp, sfpa); + tcg_temp_free_i32(sfpa); + /* + * Store result before updating FPSCR etc, in case + * it is a memory write which causes an exception. + */ + storefn(s, opaque, tmp, true); + /* + * Now we must reset FPSCR from FPDSCR_NS, and clear + * CONTROL.SFPA; so we'll end the TB here. + */ + tcg_gen_andi_i32(control, control, ~R_V7M_CONTROL_SFPA_MASK); + store_cpu_field(control, v7m.control[M_REG_S]); + fpscr = load_cpu_field(v7m.fpdscr[M_REG_NS]); + gen_helper_vfp_set_fpscr(cpu_env, fpscr); + tcg_temp_free_i32(fpscr); + lookup_tb = true; + break; + } + case ARM_VFP_FPCXT_NS: + { + TCGv_i32 control, sfpa, fpscr, fpdscr; + TCGLabel *lab_active = gen_new_label(); + + lookup_tb = true; + + gen_branch_fpInactive(s, TCG_COND_EQ, lab_active); + /* fpInactive case: reads as FPDSCR_NS */ + TCGv_i32 tmp = load_cpu_field(v7m.fpdscr[M_REG_NS]); + storefn(s, opaque, tmp, true); + lab_end = gen_new_label(); + tcg_gen_br(lab_end); + + gen_set_label(lab_active); + /* + * !fpInactive: if FPU disabled, take NOCP exception; + * otherwise PreserveFPState(), and then FPCXT_NS + * reads the same as FPCXT_S. + */ + if (!vfp_access_check_m(s, true)) { + /* + * This was only a conditional exception, so override + * gen_exception_insn_el()'s default to DISAS_NORETURN + */ + s->base.is_jmp = DISAS_NEXT; + break; + } + tmp = tcg_temp_new_i32(); + sfpa = tcg_temp_new_i32(); + fpscr = tcg_temp_new_i32(); + gen_helper_vfp_get_fpscr(fpscr, cpu_env); + tcg_gen_andi_i32(tmp, fpscr, ~FPCR_NZCV_MASK); + control = load_cpu_field(v7m.control[M_REG_S]); + tcg_gen_andi_i32(sfpa, control, R_V7M_CONTROL_SFPA_MASK); + tcg_gen_shli_i32(sfpa, sfpa, 31 - R_V7M_CONTROL_SFPA_SHIFT); + tcg_gen_or_i32(tmp, tmp, sfpa); + tcg_temp_free_i32(control); + /* Store result before updating FPSCR, in case it faults */ + storefn(s, opaque, tmp, true); + /* If SFPA is zero then set FPSCR from FPDSCR_NS */ + fpdscr = load_cpu_field(v7m.fpdscr[M_REG_NS]); + tcg_gen_movcond_i32(TCG_COND_EQ, fpscr, sfpa, tcg_constant_i32(0), + fpdscr, fpscr); + gen_helper_vfp_set_fpscr(cpu_env, fpscr); + tcg_temp_free_i32(sfpa); + tcg_temp_free_i32(fpdscr); + tcg_temp_free_i32(fpscr); + break; + } + case ARM_VFP_VPR: + /* Behaves as NOP if not privileged */ + if (IS_USER(s)) { + storefn(s, opaque, NULL, false); + break; + } + tmp = load_cpu_field(v7m.vpr); + storefn(s, opaque, tmp, true); + break; + case ARM_VFP_P0: + tmp = load_cpu_field(v7m.vpr); + tcg_gen_extract_i32(tmp, tmp, R_V7M_VPR_P0_SHIFT, R_V7M_VPR_P0_LENGTH); + storefn(s, opaque, tmp, true); + break; + default: + g_assert_not_reached(); + } + + if (lab_end) { + gen_set_label(lab_end); + } + if (lookup_tb) { + gen_lookup_tb(s); + } + return true; +} + +static void fp_sysreg_to_gpr(DisasContext *s, void *opaque, TCGv_i32 value, + bool do_access) +{ + arg_VMSR_VMRS *a = opaque; + + if (!do_access) { + return; + } + + if (a->rt == 15) { + /* Set the 4 flag bits in the CPSR */ + gen_set_nzcv(value); + tcg_temp_free_i32(value); + } else { + store_reg(s, a->rt, value); + } +} + +static TCGv_i32 gpr_to_fp_sysreg(DisasContext *s, void *opaque, bool do_access) +{ + arg_VMSR_VMRS *a = opaque; + + if (!do_access) { + return NULL; + } + return load_reg(s, a->rt); +} + +static bool trans_VMSR_VMRS(DisasContext *s, arg_VMSR_VMRS *a) +{ + /* + * Accesses to R15 are UNPREDICTABLE; we choose to undef. + * FPSCR -> r15 is a special case which writes to the PSR flags; + * set a->reg to a special value to tell gen_M_fp_sysreg_read() + * we only care about the top 4 bits of FPSCR there. + */ + if (a->rt == 15) { + if (a->l && a->reg == ARM_VFP_FPSCR) { + a->reg = QEMU_VFP_FPSCR_NZCV; + } else { + return false; + } + } + + if (a->l) { + /* VMRS, move FP system register to gp register */ + return gen_M_fp_sysreg_read(s, a->reg, fp_sysreg_to_gpr, a); + } else { + /* VMSR, move gp register to FP system register */ + return gen_M_fp_sysreg_write(s, a->reg, gpr_to_fp_sysreg, a); + } +} + +static void fp_sysreg_to_memory(DisasContext *s, void *opaque, TCGv_i32 value, + bool do_access) +{ + arg_vldr_sysreg *a = opaque; + uint32_t offset = a->imm; + TCGv_i32 addr; + + if (!a->a) { + offset = -offset; + } + + if (!do_access && !a->w) { + return; + } + + addr = load_reg(s, a->rn); + if (a->p) { + tcg_gen_addi_i32(addr, addr, offset); + } + + if (s->v8m_stackcheck && a->rn == 13 && a->w) { + gen_helper_v8m_stackcheck(cpu_env, addr); + } + + if (do_access) { + gen_aa32_st_i32(s, value, addr, get_mem_index(s), + MO_UL | MO_ALIGN | s->be_data); + tcg_temp_free_i32(value); + } + + if (a->w) { + /* writeback */ + if (!a->p) { + tcg_gen_addi_i32(addr, addr, offset); + } + store_reg(s, a->rn, addr); + } else { + tcg_temp_free_i32(addr); + } +} + +static TCGv_i32 memory_to_fp_sysreg(DisasContext *s, void *opaque, + bool do_access) +{ + arg_vldr_sysreg *a = opaque; + uint32_t offset = a->imm; + TCGv_i32 addr; + TCGv_i32 value = NULL; + + if (!a->a) { + offset = -offset; + } + + if (!do_access && !a->w) { + return NULL; + } + + addr = load_reg(s, a->rn); + if (a->p) { + tcg_gen_addi_i32(addr, addr, offset); + } + + if (s->v8m_stackcheck && a->rn == 13 && a->w) { + gen_helper_v8m_stackcheck(cpu_env, addr); + } + + if (do_access) { + value = tcg_temp_new_i32(); + gen_aa32_ld_i32(s, value, addr, get_mem_index(s), + MO_UL | MO_ALIGN | s->be_data); + } + + if (a->w) { + /* writeback */ + if (!a->p) { + tcg_gen_addi_i32(addr, addr, offset); + } + store_reg(s, a->rn, addr); + } else { + tcg_temp_free_i32(addr); + } + return value; +} + +static bool trans_VLDR_sysreg(DisasContext *s, arg_vldr_sysreg *a) +{ + if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { + return false; + } + if (a->rn == 15) { + return false; + } + return gen_M_fp_sysreg_write(s, a->reg, memory_to_fp_sysreg, a); +} + +static bool trans_VSTR_sysreg(DisasContext *s, arg_vldr_sysreg *a) +{ + if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { + return false; + } + if (a->rn == 15) { + return false; + } + return gen_M_fp_sysreg_read(s, a->reg, fp_sysreg_to_memory, a); +} + +static bool trans_NOCP(DisasContext *s, arg_nocp *a) +{ + /* + * Handle M-profile early check for disabled coprocessor: + * all we need to do here is emit the NOCP exception if + * the coprocessor is disabled. Otherwise we return false + * and the real VFP/etc decode will handle the insn. + */ + assert(arm_dc_feature(s, ARM_FEATURE_M)); + + if (a->cp == 11) { + a->cp = 10; + } + if (arm_dc_feature(s, ARM_FEATURE_V8_1M) && + (a->cp == 8 || a->cp == 9 || a->cp == 14 || a->cp == 15)) { + /* in v8.1M cp 8, 9, 14, 15 also are governed by the cp10 enable */ + a->cp = 10; + } + + if (a->cp != 10) { + gen_exception_insn(s, 0, EXCP_NOCP, syn_uncategorized()); + return true; + } + + if (s->fp_excp_el != 0) { + gen_exception_insn_el(s, 0, EXCP_NOCP, + syn_uncategorized(), s->fp_excp_el); + return true; + } + + return false; +} + +static bool trans_NOCP_8_1(DisasContext *s, arg_nocp *a) +{ + /* This range needs a coprocessor check for v8.1M and later only */ + if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { + return false; + } + return trans_NOCP(s, a); +} |