Implement the exclusive variants of qemu_{ld,st}_{i32,i64} for tcg-arm. The lookup for the proper memory helper has been rewritten to take into account the new exclusive helpers.
Suggested-by: Jani Kokkonen <jani.kokko...@huawei.com> Suggested-by: Claudio Fontana <claudio.font...@huawei.com> Signed-off-by: Alvise Rigo <a.r...@virtualopensystems.com> --- tcg/arm/tcg-target.c | 152 ++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 119 insertions(+), 33 deletions(-) diff --git a/tcg/arm/tcg-target.c b/tcg/arm/tcg-target.c index ae2ec7a..c2fae5e 100644 --- a/tcg/arm/tcg-target.c +++ b/tcg/arm/tcg-target.c @@ -1069,6 +1069,42 @@ static void * const qemu_ld_helpers[16] = { [MO_BESL] = helper_be_ldul_mmu, }; +/* LoadLink helpers, only unsigned. Use the macro below to access them. */ +static void * const qemu_ldex_helpers[16] = { + [MO_UB] = helper_ret_ldlinkub_mmu, + + [MO_LEUW] = helper_le_ldlinkuw_mmu, + [MO_LEUL] = helper_le_ldlinkul_mmu, + [MO_LEQ] = helper_le_ldlinkq_mmu, + + [MO_BEUW] = helper_be_ldlinkuw_mmu, + [MO_BEUL] = helper_be_ldlinkul_mmu, + [MO_BEQ] = helper_be_ldlinkq_mmu, +}; + +static inline tcg_insn_unit *ld_helper(TCGMemOp *opc) +{ + if (*opc & MO_EXCL) { + /* No signed-extended exclusive variants for ARM. */ + assert(!(*opc & MO_SIGN)); + + return qemu_ldex_helpers[((int)*opc - MO_EXCL) & (MO_BSWAP | MO_SSIZE)]; + } else { + /* For armv6 we can use the canonical unsigned helpers and minimize + icache usage. For pre-armv6, use the signed helpers since we do + not have a single insn sign-extend. */ + if (!use_armv6_instructions) { + if (*opc & MO_SIGN) { + *opc = MO_UL; + } + + return qemu_ld_helpers[*opc & (MO_BSWAP | MO_SSIZE)]; + } + } + + return qemu_ld_helpers[*opc & (MO_BSWAP | MO_SIZE)]; +} + /* helper signature: helper_ret_st_mmu(CPUState *env, target_ulong addr, * uintxx_t val, int mmu_idx, uintptr_t ra) */ @@ -1082,6 +1118,26 @@ static void * const qemu_st_helpers[16] = { [MO_BEQ] = helper_be_stq_mmu, }; +/* StoreConditional helpers. Use the macro below to access them. */ +static void * const qemu_stex_helpers[16] = { + [MO_UB] = helper_ret_stcondb_mmu, + [MO_LEUW] = helper_le_stcondw_mmu, + [MO_LEUL] = helper_le_stcondl_mmu, + [MO_LEQ] = helper_le_stcondq_mmu, + [MO_BEUW] = helper_be_stcondw_mmu, + [MO_BEUL] = helper_be_stcondl_mmu, + [MO_BEQ] = helper_be_stcondq_mmu, +}; + +static inline tcg_insn_unit *st_helper(TCGMemOp *opc) +{ + if (*opc & MO_EXCL) { + return qemu_stex_helpers[((int)*opc - MO_EXCL) & (MO_BSWAP | MO_SSIZE)]; + } + + return qemu_st_helpers[*opc & (MO_BSWAP | MO_SIZE)]; +} + /* Helper routines for marshalling helper function arguments into * the correct registers and stack. * argreg is where we want to put this argument, arg is the argument itself. @@ -1222,13 +1278,14 @@ static TCGReg tcg_out_tlb_read(TCGContext *s, TCGReg addrlo, TCGReg addrhi, path for a load or store, so that we can later generate the correct helper code. */ static void add_qemu_ldst_label(TCGContext *s, bool is_ld, TCGMemOpIdx oi, - TCGReg datalo, TCGReg datahi, TCGReg addrlo, - TCGReg addrhi, tcg_insn_unit *raddr, - tcg_insn_unit *label_ptr) + TCGReg llsc_success, TCGReg datalo, + TCGReg datahi, TCGReg addrlo, TCGReg addrhi, + tcg_insn_unit *raddr, tcg_insn_unit *label_ptr) { TCGLabelQemuLdst *label = new_ldst_label(s); label->is_ld = is_ld; + label->llsc_success = llsc_success; label->oi = oi; label->datalo_reg = datalo; label->datahi_reg = datahi; @@ -1256,17 +1313,7 @@ static void tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *lb) argreg = tcg_out_arg_imm32(s, argreg, oi); argreg = tcg_out_arg_reg32(s, argreg, TCG_REG_R14); - /* For armv6 we can use the canonical unsigned helpers and minimize - icache usage. For pre-armv6, use the signed helpers since we do - not have a single insn sign-extend. */ - if (use_armv6_instructions) { - func = qemu_ld_helpers[opc & (MO_BSWAP | MO_SIZE)]; - } else { - func = qemu_ld_helpers[opc & (MO_BSWAP | MO_SSIZE)]; - if (opc & MO_SIGN) { - opc = MO_UL; - } - } + func = ld_helper(&opc); tcg_out_call(s, func); datalo = lb->datalo_reg; @@ -1336,8 +1383,15 @@ static void tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *lb) argreg = tcg_out_arg_imm32(s, argreg, oi); argreg = tcg_out_arg_reg32(s, argreg, TCG_REG_R14); - /* Tail-call to the helper, which will return to the fast path. */ - tcg_out_goto(s, COND_AL, qemu_st_helpers[opc & (MO_BSWAP | MO_SIZE)]); + if (opc & MO_EXCL) { + tcg_out_call(s, st_helper(&opc)); + /* Save the output of the StoreConditional */ + tcg_out_mov_reg(s, COND_AL, lb->llsc_success, TCG_REG_R0); + tcg_out_goto(s, COND_AL, lb->raddr); + } else { + /* Tail-call to the helper, which will return to the fast path. */ + tcg_out_goto(s, COND_AL, st_helper(&opc)); + } } #endif /* SOFTMMU */ @@ -1468,7 +1522,6 @@ static void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args, bool is64) TCGMemOp opc; #ifdef CONFIG_SOFTMMU int mem_index; - TCGReg addend; tcg_insn_unit *label_ptr; #endif @@ -1481,16 +1534,26 @@ static void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args, bool is64) #ifdef CONFIG_SOFTMMU mem_index = get_mmuidx(oi); - addend = tcg_out_tlb_read(s, addrlo, addrhi, opc & MO_SIZE, mem_index, 1); /* This a conditional BL only to load a pointer within this opcode into LR - for the slow path. We will not be using the value for a tail call. */ - label_ptr = s->code_ptr; - tcg_out_bl_noaddr(s, COND_NE); + for the slow path. We will not be using the value for a tail call. + In the context of a LoadLink instruction, we don't check the TLB but we + always follow the slow path. */ + if (opc & MO_EXCL) { + label_ptr = s->code_ptr; + tcg_out_bl_noaddr(s, COND_AL); + } else { + TCGReg addend; - tcg_out_qemu_ld_index(s, opc, datalo, datahi, addrlo, addend); + addend = tcg_out_tlb_read(s, addrlo, addrhi, opc & MO_SIZE, + mem_index, 1); + label_ptr = s->code_ptr; + tcg_out_bl_noaddr(s, COND_NE); - add_qemu_ldst_label(s, true, oi, datalo, datahi, addrlo, addrhi, + tcg_out_qemu_ld_index(s, opc, datalo, datahi, addrlo, addend); + } + + add_qemu_ldst_label(s, true, oi, 0, datalo, datahi, addrlo, addrhi, s->code_ptr, label_ptr); #else /* !CONFIG_SOFTMMU */ if (GUEST_BASE) { @@ -1592,15 +1655,20 @@ static inline void tcg_out_qemu_st_direct(TCGContext *s, TCGMemOp opc, } } -static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, bool is64) +static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, bool is64, + bool isStoreCond) { TCGReg addrlo, datalo, datahi, addrhi __attribute__((unused)); TCGMemOpIdx oi; TCGMemOp opc; #ifdef CONFIG_SOFTMMU + TCGReg llsc_success; int mem_index; TCGReg addend; tcg_insn_unit *label_ptr; + + /* The stcond variant has one more param */ + llsc_success = (isStoreCond ? *args++ : 0); #endif datalo = *args++; @@ -1612,16 +1680,24 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, bool is64) #ifdef CONFIG_SOFTMMU mem_index = get_mmuidx(oi); - addend = tcg_out_tlb_read(s, addrlo, addrhi, opc & MO_SIZE, mem_index, 0); - tcg_out_qemu_st_index(s, COND_EQ, opc, datalo, datahi, addrlo, addend); + if (isStoreCond) { + /* Always follow the slow-path for an exclusive access */ + label_ptr = s->code_ptr; + tcg_out_bl_noaddr(s, COND_AL); + } else { + addend = tcg_out_tlb_read(s, addrlo, addrhi, opc & MO_SIZE, + mem_index, 0); - /* The conditional call must come last, as we're going to return here. */ - label_ptr = s->code_ptr; - tcg_out_bl_noaddr(s, COND_NE); + tcg_out_qemu_st_index(s, COND_EQ, opc, datalo, datahi, addrlo, addend); - add_qemu_ldst_label(s, false, oi, datalo, datahi, addrlo, addrhi, - s->code_ptr, label_ptr); + /* The conditional call must come last, as we're going to return here.*/ + label_ptr = s->code_ptr; + tcg_out_bl_noaddr(s, COND_NE); + } + + add_qemu_ldst_label(s, false, oi, llsc_success, datalo, datahi, addrlo, + addrhi, s->code_ptr, label_ptr); #else /* !CONFIG_SOFTMMU */ if (GUEST_BASE) { tcg_out_movi(s, TCG_TYPE_PTR, TCG_REG_TMP, GUEST_BASE); @@ -1870,10 +1946,16 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc, tcg_out_qemu_ld(s, args, 1); break; case INDEX_op_qemu_st_i32: - tcg_out_qemu_st(s, args, 0); + tcg_out_qemu_st(s, args, 0, 0); + break; + case INDEX_op_qemu_stcond_i32: + tcg_out_qemu_st(s, args, 0, 1); /* StoreConditional */ break; case INDEX_op_qemu_st_i64: - tcg_out_qemu_st(s, args, 1); + tcg_out_qemu_st(s, args, 1, 0); + break; + case INDEX_op_qemu_stcond_i64: + tcg_out_qemu_st(s, args, 1, 1); /* StoreConditional */ break; case INDEX_op_bswap16_i32: @@ -1959,12 +2041,16 @@ static const TCGTargetOpDef arm_op_defs[] = { { INDEX_op_qemu_ld_i32, { "r", "l" } }, { INDEX_op_qemu_ld_i64, { "r", "r", "l" } }, { INDEX_op_qemu_st_i32, { "s", "s" } }, + { INDEX_op_qemu_stcond_i32, { "r", "s", "s" } }, { INDEX_op_qemu_st_i64, { "s", "s", "s" } }, + { INDEX_op_qemu_stcond_i64, { "r", "s", "s", "s" } }, #else { INDEX_op_qemu_ld_i32, { "r", "l", "l" } }, { INDEX_op_qemu_ld_i64, { "r", "r", "l", "l" } }, { INDEX_op_qemu_st_i32, { "s", "s", "s" } }, + { INDEX_op_qemu_stcond_i32, { "r", "s", "s", "s" } }, { INDEX_op_qemu_st_i64, { "s", "s", "s", "s" } }, + { INDEX_op_qemu_stcond_i64, { "r", "s", "s", "s", "s" } }, #endif { INDEX_op_bswap16_i32, { "r", "r" } }, -- 2.5.0