From d63aeb3b7ea770dac4ab13eb1e19a943a198a28d Mon Sep 17 00:00:00 2001 From: Marco Liebel Date: Thu, 5 Jan 2023 02:23:49 -0800 Subject: [PATCH] Hexagon (target/hexagon) implement mutability mask for GPRs Some registers are defined to have immutable bits, this commit will implement that behavior. Signed-off-by: Marco Liebel Reviewed-by: Taylor Simpson Signed-off-by: Taylor Simpson Message-Id: <20230105102349.2181856-1-quic_mliebel@quicinc.com> --- target/hexagon/genptr.c | 44 ++++++++- tests/tcg/hexagon/Makefile.target | 1 + tests/tcg/hexagon/reg_mut.c | 152 ++++++++++++++++++++++++++++++ 3 files changed, 195 insertions(+), 2 deletions(-) create mode 100644 tests/tcg/hexagon/reg_mut.c diff --git a/target/hexagon/genptr.c b/target/hexagon/genptr.c index 66a968c884..90db99024f 100644 --- a/target/hexagon/genptr.c +++ b/target/hexagon/genptr.c @@ -43,6 +43,33 @@ TCGv gen_read_preg(TCGv pred, uint8_t num) return pred; } +#define IMMUTABLE (~0) + +static const target_ulong reg_immut_masks[TOTAL_PER_THREAD_REGS] = { + [HEX_REG_USR] = 0xc13000c0, + [HEX_REG_PC] = IMMUTABLE, + [HEX_REG_GP] = 0x3f, + [HEX_REG_UPCYCLELO] = IMMUTABLE, + [HEX_REG_UPCYCLEHI] = IMMUTABLE, + [HEX_REG_UTIMERLO] = IMMUTABLE, + [HEX_REG_UTIMERHI] = IMMUTABLE, +}; + +static inline void gen_masked_reg_write(TCGv new_val, TCGv cur_val, + target_ulong reg_mask) +{ + if (reg_mask) { + TCGv tmp = tcg_temp_new(); + + /* new_val = (new_val & ~reg_mask) | (cur_val & reg_mask) */ + tcg_gen_andi_tl(new_val, new_val, ~reg_mask); + tcg_gen_andi_tl(tmp, cur_val, reg_mask); + tcg_gen_or_tl(new_val, new_val, tmp); + + tcg_temp_free(tmp); + } +} + static inline void gen_log_predicated_reg_write(int rnum, TCGv val, uint32_t slot) { @@ -69,6 +96,9 @@ static inline void gen_log_predicated_reg_write(int rnum, TCGv val, void gen_log_reg_write(int rnum, TCGv val) { + const target_ulong reg_mask = reg_immut_masks[rnum]; + + gen_masked_reg_write(val, hex_gpr[rnum], reg_mask); tcg_gen_mov_tl(hex_new_value[rnum], val); if (HEX_DEBUG) { /* Do this so HELPER(debug_commit_end) will know */ @@ -114,19 +144,29 @@ static void gen_log_predicated_reg_write_pair(int rnum, TCGv_i64 val, static void gen_log_reg_write_pair(int rnum, TCGv_i64 val) { + const target_ulong reg_mask_low = reg_immut_masks[rnum]; + const target_ulong reg_mask_high = reg_immut_masks[rnum + 1]; + TCGv val32 = tcg_temp_new(); + /* Low word */ - tcg_gen_extrl_i64_i32(hex_new_value[rnum], val); + tcg_gen_extrl_i64_i32(val32, val); + gen_masked_reg_write(val32, hex_gpr[rnum], reg_mask_low); + tcg_gen_mov_tl(hex_new_value[rnum], val32); if (HEX_DEBUG) { /* Do this so HELPER(debug_commit_end) will know */ tcg_gen_movi_tl(hex_reg_written[rnum], 1); } /* High word */ - tcg_gen_extrh_i64_i32(hex_new_value[rnum + 1], val); + tcg_gen_extrh_i64_i32(val32, val); + gen_masked_reg_write(val32, hex_gpr[rnum + 1], reg_mask_high); + tcg_gen_mov_tl(hex_new_value[rnum + 1], val32); if (HEX_DEBUG) { /* Do this so HELPER(debug_commit_end) will know */ tcg_gen_movi_tl(hex_reg_written[rnum + 1], 1); } + + tcg_temp_free(val32); } void gen_log_pred_write(DisasContext *ctx, int pnum, TCGv val) diff --git a/tests/tcg/hexagon/Makefile.target b/tests/tcg/hexagon/Makefile.target index f1378d86a9..18e6a5969e 100644 --- a/tests/tcg/hexagon/Makefile.target +++ b/tests/tcg/hexagon/Makefile.target @@ -44,6 +44,7 @@ HEX_TESTS += atomics HEX_TESTS += fpstuff HEX_TESTS += overflow HEX_TESTS += signal_context +HEX_TESTS += reg_mut HEX_TESTS += test_abs HEX_TESTS += test_bitcnt diff --git a/tests/tcg/hexagon/reg_mut.c b/tests/tcg/hexagon/reg_mut.c new file mode 100644 index 0000000000..910e663ace --- /dev/null +++ b/tests/tcg/hexagon/reg_mut.c @@ -0,0 +1,152 @@ + +/* + * Copyright(c) 2022 Qualcomm Innovation Center, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#include +#include + +static int err; + +#define check(N, EXPECT) \ + do { \ + uint64_t value = N; \ + uint64_t expect = EXPECT; \ + if (value != EXPECT) { \ + printf("ERROR: \"%s\" 0x%04llx != 0x%04llx at %s:%d\n", #N, value, \ + expect, __FILE__, __LINE__); \ + err++; \ + } \ + } while (0) + +#define check_ne(N, EXPECT) \ + do { \ + uint64_t value = N; \ + uint64_t expect = EXPECT; \ + if (value == EXPECT) { \ + printf("ERROR: \"%s\" 0x%04llx == 0x%04llx at %s:%d\n", #N, value, \ + expect, __FILE__, __LINE__); \ + err++; \ + } \ + } while (0) + +#define WRITE_REG_NOCLOBBER(output, reg_name, input) \ + asm volatile(reg_name " = %1\n\t" \ + "%0 = " reg_name "\n\t" \ + : "=r"(output) \ + : "r"(input) \ + : ); + +#define WRITE_REG_ENCODED(output, reg_name, input, encoding) \ + asm volatile("r0 = %1\n\t" \ + encoding "\n\t" \ + "%0 = " reg_name "\n\t" \ + : "=r"(output) \ + : "r"(input) \ + : "r0"); + +#define WRITE_REG_PAIR_ENCODED(output, reg_name, input, encoding) \ + asm volatile("r1:0 = %1\n\t" \ + encoding "\n\t" \ + "%0 = " reg_name "\n\t" \ + : "=r"(output) \ + : "r"(input) \ + : "r1:0"); + +/* + * Instruction word: { pc = r0 } + * + * This instruction is barred by the assembler. + * + * 3 2 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Opc[A2_tfrrcr] | Src[R0] |P P| | C9/PC | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ +#define PC_EQ_R0 ".word 0x6220c009" +#define C9_8_EQ_R1_0 ".word 0x6320c008" + +static inline void write_control_registers(void) +{ + uint32_t result = 0; + + WRITE_REG_NOCLOBBER(result, "usr", 0xffffffff); + check(result, 0x3ecfff3f); + + WRITE_REG_NOCLOBBER(result, "gp", 0xffffffff); + check(result, 0xffffffc0); + + WRITE_REG_NOCLOBBER(result, "upcyclelo", 0xffffffff); + check(result, 0x00000000); + + WRITE_REG_NOCLOBBER(result, "upcyclehi", 0xffffffff); + check(result, 0x00000000); + + WRITE_REG_NOCLOBBER(result, "utimerlo", 0xffffffff); + check(result, 0x00000000); + + WRITE_REG_NOCLOBBER(result, "utimerhi", 0xffffffff); + check(result, 0x00000000); + + /* + * PC is special. Setting it to these values + * should cause a catastrophic failure. + */ + WRITE_REG_ENCODED(result, "pc", 0x00000000, PC_EQ_R0); + check_ne(result, 0x00000000); + + WRITE_REG_ENCODED(result, "pc", 0x00000001, PC_EQ_R0); + check_ne(result, 0x00000001); + + WRITE_REG_ENCODED(result, "pc", 0xffffffff, PC_EQ_R0); + check_ne(result, 0xffffffff); +} + +static inline void write_control_register_pairs(void) +{ + uint64_t result = 0; + + WRITE_REG_NOCLOBBER(result, "c11:10", 0xffffffffffffffff); + check(result, 0xffffffc0ffffffff); + + WRITE_REG_NOCLOBBER(result, "c15:14", 0xffffffffffffffff); + check(result, 0x0000000000000000); + + WRITE_REG_NOCLOBBER(result, "c31:30", 0xffffffffffffffff); + check(result, 0x0000000000000000); + + WRITE_REG_PAIR_ENCODED(result, "c9:8", (uint64_t) 0x0000000000000000, + C9_8_EQ_R1_0); + check_ne(result, 0x000000000000000); + + WRITE_REG_PAIR_ENCODED(result, "c9:8", 0x0000000100000000, C9_8_EQ_R1_0); + check_ne(result, 0x0000000100000000); + + WRITE_REG_PAIR_ENCODED(result, "c9:8", 0xffffffffffffffff, C9_8_EQ_R1_0); + check_ne(result, 0xffffffffffffffff); +} + +int main() +{ + err = 0; + + write_control_registers(); + write_control_register_pairs(); + + puts(err ? "FAIL" : "PASS"); + return err; +}