From da54941f45b820cbaca72aa6efd5669b3dc86e2f Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 25 Jun 2020 20:31:07 -0700 Subject: [PATCH] target/arm: Implement the IRG instruction Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-id: 20200626033144.790098-10-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- target/arm/Makefile.objs | 1 + target/arm/helper-a64.h | 2 ++ target/arm/internals.h | 5 +++ target/arm/mte_helper.c | 72 ++++++++++++++++++++++++++++++++++++++ target/arm/translate-a64.c | 18 ++++++++++ 5 files changed, 98 insertions(+) create mode 100644 target/arm/mte_helper.c diff --git a/target/arm/Makefile.objs b/target/arm/Makefile.objs index 83febd232c..fa39fd7c83 100644 --- a/target/arm/Makefile.objs +++ b/target/arm/Makefile.objs @@ -86,3 +86,4 @@ obj-$(CONFIG_SOFTMMU) += psci.o obj-$(TARGET_AARCH64) += translate-a64.o helper-a64.o obj-$(TARGET_AARCH64) += translate-sve.o sve_helper.o obj-$(TARGET_AARCH64) += pauth_helper.o +obj-$(TARGET_AARCH64) += mte_helper.o diff --git a/target/arm/helper-a64.h b/target/arm/helper-a64.h index 3df7c185aa..587ccbe42f 100644 --- a/target/arm/helper-a64.h +++ b/target/arm/helper-a64.h @@ -103,3 +103,5 @@ DEF_HELPER_FLAGS_3(autda, TCG_CALL_NO_WG, i64, env, i64, i64) DEF_HELPER_FLAGS_3(autdb, TCG_CALL_NO_WG, i64, env, i64, i64) DEF_HELPER_FLAGS_2(xpaci, TCG_CALL_NO_RWG_SE, i64, env, i64) DEF_HELPER_FLAGS_2(xpacd, TCG_CALL_NO_RWG_SE, i64, env, i64) + +DEF_HELPER_FLAGS_3(irg, TCG_CALL_NO_RWG, i64, env, i64, i64) diff --git a/target/arm/internals.h b/target/arm/internals.h index 53e249687b..ae611a6ff5 100644 --- a/target/arm/internals.h +++ b/target/arm/internals.h @@ -1261,4 +1261,9 @@ void arm_log_exception(int idx); */ #define GMID_EL1_BS 6 +static inline uint64_t address_with_allocation_tag(uint64_t ptr, int rtag) +{ + return deposit64(ptr, 56, 4, rtag); +} + #endif diff --git a/target/arm/mte_helper.c b/target/arm/mte_helper.c new file mode 100644 index 0000000000..539a04de84 --- /dev/null +++ b/target/arm/mte_helper.c @@ -0,0 +1,72 @@ +/* + * ARM v8.5-MemTag Operations + * + * 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 . + */ + +#include "qemu/osdep.h" +#include "cpu.h" +#include "internals.h" +#include "exec/exec-all.h" +#include "exec/cpu_ldst.h" +#include "exec/helper-proto.h" + + +static int choose_nonexcluded_tag(int tag, int offset, uint16_t exclude) +{ + if (exclude == 0xffff) { + return 0; + } + if (offset == 0) { + while (exclude & (1 << tag)) { + tag = (tag + 1) & 15; + } + } else { + do { + do { + tag = (tag + 1) & 15; + } while (exclude & (1 << tag)); + } while (--offset > 0); + } + return tag; +} + +uint64_t HELPER(irg)(CPUARMState *env, uint64_t rn, uint64_t rm) +{ + int rtag; + + /* + * Our IMPDEF choice for GCR_EL1.RRND==1 is to behave as if + * GCR_EL1.RRND==0, always producing deterministic results. + */ + uint16_t exclude = extract32(rm | env->cp15.gcr_el1, 0, 16); + int start = extract32(env->cp15.rgsr_el1, 0, 4); + int seed = extract32(env->cp15.rgsr_el1, 8, 16); + int offset, i; + + /* RandomTag */ + for (i = offset = 0; i < 4; ++i) { + /* NextRandomTagBit */ + int top = (extract32(seed, 5, 1) ^ extract32(seed, 3, 1) ^ + extract32(seed, 2, 1) ^ extract32(seed, 0, 1)); + seed = (top << 15) | (seed >> 1); + offset |= top << i; + } + rtag = choose_nonexcluded_tag(start, offset, exclude); + env->cp15.rgsr_el1 = rtag | (seed << 8); + + return address_with_allocation_tag(rn, rtag); +} diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index 55f49585be..30683061f9 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -226,6 +226,12 @@ static TCGv_i64 clean_data_tbi(DisasContext *s, TCGv_i64 addr) return clean; } +/* Insert a zero tag into src, with the result at dst. */ +static void gen_address_with_allocation_tag0(TCGv_i64 dst, TCGv_i64 src) +{ + tcg_gen_andi_i64(dst, src, ~MAKE_64BIT_MASK(56, 4)); +} + typedef struct DisasCompare64 { TCGCond cond; TCGv_i64 value; @@ -5284,6 +5290,18 @@ static void disas_data_proc_2src(DisasContext *s, uint32_t insn) case 3: /* SDIV */ handle_div(s, true, sf, rm, rn, rd); break; + case 4: /* IRG */ + if (sf == 0 || !dc_isar_feature(aa64_mte_insn_reg, s)) { + goto do_unallocated; + } + if (s->ata) { + gen_helper_irg(cpu_reg_sp(s, rd), cpu_env, + cpu_reg_sp(s, rn), cpu_reg(s, rm)); + } else { + gen_address_with_allocation_tag0(cpu_reg_sp(s, rd), + cpu_reg_sp(s, rn)); + } + break; case 8: /* LSLV */ handle_shift_reg(s, A64_SHIFT_TYPE_LSL, sf, rm, rn, rd); break;