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([212.241.182.8]) by smtp.gmail.com with ESMTPSA id x9-20020adfec09000000b002faaa9a1721sm4481223wrn.58.2023.05.06.00.22.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 06 May 2023 00:22:43 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Cc: git@xen0n.name, gaosong@loongson.cn, philmd@linaro.org, qemu-arm@nongnu.org, qemu-riscv@nongnu.org, qemu-s390x@nongnu.org Subject: [PATCH v5 09/30] tcg/s390x: Introduce prepare_host_addr Date: Sat, 6 May 2023 08:22:14 +0100 Message-Id: <20230506072235.597467-10-richard.henderson@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230506072235.597467-1-richard.henderson@linaro.org> References: <20230506072235.597467-1-richard.henderson@linaro.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2a00:1450:4864:20::42c; envelope-from=richard.henderson@linaro.org; helo=mail-wr1-x42c.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patch=linaro.org@nongnu.org Sender: qemu-devel-bounces+patch=linaro.org@nongnu.org Merge tcg_out_tlb_load, add_qemu_ldst_label, tcg_out_test_alignment, tcg_prepare_user_ldst, and some code that lived in both tcg_out_qemu_ld and tcg_out_qemu_st into one function that returns HostAddress and TCGLabelQemuLdst structures. Signed-off-by: Richard Henderson Reviewed-by: Alex Bennée --- tcg/s390x/tcg-target.c.inc | 263 ++++++++++++++++--------------------- 1 file changed, 113 insertions(+), 150 deletions(-) diff --git a/tcg/s390x/tcg-target.c.inc b/tcg/s390x/tcg-target.c.inc index da7ee5b085..c3157d22be 100644 --- a/tcg/s390x/tcg-target.c.inc +++ b/tcg/s390x/tcg-target.c.inc @@ -1718,78 +1718,6 @@ static void tcg_out_qemu_st_direct(TCGContext *s, MemOp opc, TCGReg data, } #if defined(CONFIG_SOFTMMU) -/* We're expecting to use a 20-bit negative offset on the tlb memory ops. */ -QEMU_BUILD_BUG_ON(TLB_MASK_TABLE_OFS(0) > 0); -QEMU_BUILD_BUG_ON(TLB_MASK_TABLE_OFS(0) < -(1 << 19)); - -/* Load and compare a TLB entry, leaving the flags set. Loads the TLB - addend into R2. Returns a register with the santitized guest address. */ -static TCGReg tcg_out_tlb_read(TCGContext *s, TCGReg addr_reg, MemOp opc, - int mem_index, bool is_ld) -{ - unsigned s_bits = opc & MO_SIZE; - unsigned a_bits = get_alignment_bits(opc); - unsigned s_mask = (1 << s_bits) - 1; - unsigned a_mask = (1 << a_bits) - 1; - int fast_off = TLB_MASK_TABLE_OFS(mem_index); - int mask_off = fast_off + offsetof(CPUTLBDescFast, mask); - int table_off = fast_off + offsetof(CPUTLBDescFast, table); - int ofs, a_off; - uint64_t tlb_mask; - - tcg_out_sh64(s, RSY_SRLG, TCG_REG_R2, addr_reg, TCG_REG_NONE, - TARGET_PAGE_BITS - CPU_TLB_ENTRY_BITS); - tcg_out_insn(s, RXY, NG, TCG_REG_R2, TCG_AREG0, TCG_REG_NONE, mask_off); - tcg_out_insn(s, RXY, AG, TCG_REG_R2, TCG_AREG0, TCG_REG_NONE, table_off); - - /* For aligned accesses, we check the first byte and include the alignment - bits within the address. For unaligned access, we check that we don't - cross pages using the address of the last byte of the access. */ - a_off = (a_bits >= s_bits ? 0 : s_mask - a_mask); - tlb_mask = (uint64_t)TARGET_PAGE_MASK | a_mask; - if (a_off == 0) { - tgen_andi_risbg(s, TCG_REG_R3, addr_reg, tlb_mask); - } else { - tcg_out_insn(s, RX, LA, TCG_REG_R3, addr_reg, TCG_REG_NONE, a_off); - tgen_andi(s, TCG_TYPE_TL, TCG_REG_R3, tlb_mask); - } - - if (is_ld) { - ofs = offsetof(CPUTLBEntry, addr_read); - } else { - ofs = offsetof(CPUTLBEntry, addr_write); - } - if (TARGET_LONG_BITS == 32) { - tcg_out_insn(s, RX, C, TCG_REG_R3, TCG_REG_R2, TCG_REG_NONE, ofs); - } else { - tcg_out_insn(s, RXY, CG, TCG_REG_R3, TCG_REG_R2, TCG_REG_NONE, ofs); - } - - tcg_out_insn(s, RXY, LG, TCG_REG_R2, TCG_REG_R2, TCG_REG_NONE, - offsetof(CPUTLBEntry, addend)); - - if (TARGET_LONG_BITS == 32) { - tcg_out_ext32u(s, TCG_REG_R3, addr_reg); - return TCG_REG_R3; - } - return addr_reg; -} - -static void add_qemu_ldst_label(TCGContext *s, bool is_ld, MemOpIdx oi, - TCGType type, TCGReg data, TCGReg addr, - tcg_insn_unit *raddr, tcg_insn_unit *label_ptr) -{ - TCGLabelQemuLdst *label = new_ldst_label(s); - - label->is_ld = is_ld; - label->oi = oi; - label->type = type; - label->datalo_reg = data; - label->addrlo_reg = addr; - label->raddr = tcg_splitwx_to_rx(raddr); - label->label_ptr[0] = label_ptr; -} - static bool tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *lb) { TCGReg addr_reg = lb->addrlo_reg; @@ -1842,26 +1770,6 @@ static bool tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *lb) return true; } #else -static void tcg_out_test_alignment(TCGContext *s, bool is_ld, - TCGReg addrlo, unsigned a_bits) -{ - unsigned a_mask = (1 << a_bits) - 1; - TCGLabelQemuLdst *l = new_ldst_label(s); - - l->is_ld = is_ld; - l->addrlo_reg = addrlo; - - /* We are expecting a_bits to max out at 7, much lower than TMLL. */ - tcg_debug_assert(a_bits < 16); - tcg_out_insn(s, RI, TMLL, addrlo, a_mask); - - tcg_out16(s, RI_BRC | (7 << 4)); /* CC in {1,2,3} */ - l->label_ptr[0] = s->code_ptr; - s->code_ptr += 1; - - l->raddr = tcg_splitwx_to_rx(s->code_ptr); -} - static bool tcg_out_fail_alignment(TCGContext *s, TCGLabelQemuLdst *l) { if (!patch_reloc(l->label_ptr[0], R_390_PC16DBL, @@ -1888,91 +1796,146 @@ static bool tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *l) { return tcg_out_fail_alignment(s, l); } +#endif /* CONFIG_SOFTMMU */ -static HostAddress tcg_prepare_user_ldst(TCGContext *s, TCGReg addr_reg) +/* + * For softmmu, perform the TLB load and compare. + * For useronly, perform any required alignment tests. + * In both cases, return a TCGLabelQemuLdst structure if the slow path + * is required and fill in @h with the host address for the fast path. + */ +static TCGLabelQemuLdst *prepare_host_addr(TCGContext *s, HostAddress *h, + TCGReg addr_reg, MemOpIdx oi, + bool is_ld) { - TCGReg index; - int disp; + TCGLabelQemuLdst *ldst = NULL; + MemOp opc = get_memop(oi); + unsigned a_bits = get_alignment_bits(opc); + unsigned a_mask = (1u << a_bits) - 1; +#ifdef CONFIG_SOFTMMU + unsigned s_bits = opc & MO_SIZE; + unsigned s_mask = (1 << s_bits) - 1; + int mem_index = get_mmuidx(oi); + int fast_off = TLB_MASK_TABLE_OFS(mem_index); + int mask_off = fast_off + offsetof(CPUTLBDescFast, mask); + int table_off = fast_off + offsetof(CPUTLBDescFast, table); + int ofs, a_off; + uint64_t tlb_mask; + + ldst = new_ldst_label(s); + ldst->is_ld = is_ld; + ldst->oi = oi; + ldst->addrlo_reg = addr_reg; + + tcg_out_sh64(s, RSY_SRLG, TCG_REG_R2, addr_reg, TCG_REG_NONE, + TARGET_PAGE_BITS - CPU_TLB_ENTRY_BITS); + + QEMU_BUILD_BUG_ON(TLB_MASK_TABLE_OFS(0) > 0); + QEMU_BUILD_BUG_ON(TLB_MASK_TABLE_OFS(0) < -(1 << 19)); + tcg_out_insn(s, RXY, NG, TCG_REG_R2, TCG_AREG0, TCG_REG_NONE, mask_off); + tcg_out_insn(s, RXY, AG, TCG_REG_R2, TCG_AREG0, TCG_REG_NONE, table_off); + + /* + * For aligned accesses, we check the first byte and include the alignment + * bits within the address. For unaligned access, we check that we don't + * cross pages using the address of the last byte of the access. + */ + a_off = (a_bits >= s_bits ? 0 : s_mask - a_mask); + tlb_mask = (uint64_t)TARGET_PAGE_MASK | a_mask; + if (a_off == 0) { + tgen_andi_risbg(s, TCG_REG_R3, addr_reg, tlb_mask); + } else { + tcg_out_insn(s, RX, LA, TCG_REG_R3, addr_reg, TCG_REG_NONE, a_off); + tgen_andi(s, TCG_TYPE_TL, TCG_REG_R3, tlb_mask); + } + + if (is_ld) { + ofs = offsetof(CPUTLBEntry, addr_read); + } else { + ofs = offsetof(CPUTLBEntry, addr_write); + } + if (TARGET_LONG_BITS == 32) { + tcg_out_insn(s, RX, C, TCG_REG_R3, TCG_REG_R2, TCG_REG_NONE, ofs); + } else { + tcg_out_insn(s, RXY, CG, TCG_REG_R3, TCG_REG_R2, TCG_REG_NONE, ofs); + } + + tcg_out16(s, RI_BRC | (S390_CC_NE << 4)); + ldst->label_ptr[0] = s->code_ptr++; + + h->index = TCG_REG_R2; + tcg_out_insn(s, RXY, LG, h->index, TCG_REG_R2, TCG_REG_NONE, + offsetof(CPUTLBEntry, addend)); + + h->base = addr_reg; + if (TARGET_LONG_BITS == 32) { + tcg_out_ext32u(s, TCG_REG_R3, addr_reg); + h->base = TCG_REG_R3; + } + h->disp = 0; +#else + if (a_mask) { + ldst = new_ldst_label(s); + ldst->is_ld = is_ld; + ldst->oi = oi; + ldst->addrlo_reg = addr_reg; + + /* We are expecting a_bits to max out at 7, much lower than TMLL. */ + tcg_debug_assert(a_bits < 16); + tcg_out_insn(s, RI, TMLL, addr_reg, a_mask); + + tcg_out16(s, RI_BRC | (7 << 4)); /* CC in {1,2,3} */ + ldst->label_ptr[0] = s->code_ptr++; + } + + h->base = addr_reg; if (TARGET_LONG_BITS == 32) { tcg_out_ext32u(s, TCG_TMP0, addr_reg); - addr_reg = TCG_TMP0; + h->base = TCG_TMP0; } if (guest_base < 0x80000) { - index = TCG_REG_NONE; - disp = guest_base; + h->index = TCG_REG_NONE; + h->disp = guest_base; } else { - index = TCG_GUEST_BASE_REG; - disp = 0; + h->index = TCG_GUEST_BASE_REG; + h->disp = 0; } - return (HostAddress){ .base = addr_reg, .index = index, .disp = disp }; +#endif + + return ldst; } -#endif /* CONFIG_SOFTMMU */ static void tcg_out_qemu_ld(TCGContext* s, TCGReg data_reg, TCGReg addr_reg, MemOpIdx oi, TCGType data_type) { - MemOp opc = get_memop(oi); + TCGLabelQemuLdst *ldst; HostAddress h; -#ifdef CONFIG_SOFTMMU - unsigned mem_index = get_mmuidx(oi); - tcg_insn_unit *label_ptr; + ldst = prepare_host_addr(s, &h, addr_reg, oi, true); + tcg_out_qemu_ld_direct(s, get_memop(oi), data_reg, h); - h.base = tcg_out_tlb_read(s, addr_reg, opc, mem_index, 1); - h.index = TCG_REG_R2; - h.disp = 0; - - tcg_out16(s, RI_BRC | (S390_CC_NE << 4)); - label_ptr = s->code_ptr; - s->code_ptr += 1; - - tcg_out_qemu_ld_direct(s, opc, data_reg, h); - - add_qemu_ldst_label(s, true, oi, data_type, data_reg, addr_reg, - s->code_ptr, label_ptr); -#else - unsigned a_bits = get_alignment_bits(opc); - - if (a_bits) { - tcg_out_test_alignment(s, true, addr_reg, a_bits); + if (ldst) { + ldst->type = data_type; + ldst->datalo_reg = data_reg; + ldst->raddr = tcg_splitwx_to_rx(s->code_ptr); } - h = tcg_prepare_user_ldst(s, addr_reg); - tcg_out_qemu_ld_direct(s, opc, data_reg, h); -#endif } static void tcg_out_qemu_st(TCGContext* s, TCGReg data_reg, TCGReg addr_reg, MemOpIdx oi, TCGType data_type) { - MemOp opc = get_memop(oi); + TCGLabelQemuLdst *ldst; HostAddress h; -#ifdef CONFIG_SOFTMMU - unsigned mem_index = get_mmuidx(oi); - tcg_insn_unit *label_ptr; + ldst = prepare_host_addr(s, &h, addr_reg, oi, false); + tcg_out_qemu_st_direct(s, get_memop(oi), data_reg, h); - h.base = tcg_out_tlb_read(s, addr_reg, opc, mem_index, 0); - h.index = TCG_REG_R2; - h.disp = 0; - - tcg_out16(s, RI_BRC | (S390_CC_NE << 4)); - label_ptr = s->code_ptr; - s->code_ptr += 1; - - tcg_out_qemu_st_direct(s, opc, data_reg, h); - - add_qemu_ldst_label(s, false, oi, data_type, data_reg, addr_reg, - s->code_ptr, label_ptr); -#else - unsigned a_bits = get_alignment_bits(opc); - - if (a_bits) { - tcg_out_test_alignment(s, false, addr_reg, a_bits); + if (ldst) { + ldst->type = data_type; + ldst->datalo_reg = data_reg; + ldst->raddr = tcg_splitwx_to_rx(s->code_ptr); } - h = tcg_prepare_user_ldst(s, addr_reg); - tcg_out_qemu_st_direct(s, opc, data_reg, h); -#endif } static void tcg_out_exit_tb(TCGContext *s, uintptr_t a0)