From b854fd06a868e0308bcfe05ad0a71210705814c7 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 8 May 2020 08:43:51 -0700 Subject: [PATCH] target/arm: Use SVEContLdSt in sve_ld1_r First use of the new helper functions, so we can remove the unused markup. No longer need a scratch for user-only, as we completely probe the page set before reading; system mode still requires a scratch for MMIO. Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-id: 20200508154359.7494-12-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- target/arm/sve_helper.c | 188 +++++++++++++++++++++++++----------------------- 1 file changed, 97 insertions(+), 91 deletions(-) diff --git a/target/arm/sve_helper.c b/target/arm/sve_helper.c index d007137735..6bae342a17 100644 --- a/target/arm/sve_helper.c +++ b/target/arm/sve_helper.c @@ -4221,9 +4221,9 @@ typedef struct { * final element on each page. Identify any single element that spans * the page boundary. Return true if there are any active elements. */ -static bool __attribute__((unused)) -sve_cont_ldst_elements(SVEContLdSt *info, target_ulong addr, uint64_t *vg, - intptr_t reg_max, int esz, int msize) +static bool sve_cont_ldst_elements(SVEContLdSt *info, target_ulong addr, + uint64_t *vg, intptr_t reg_max, + int esz, int msize) { const int esize = 1 << esz; const uint64_t pg_mask = pred_esz_masks[esz]; @@ -4313,10 +4313,9 @@ sve_cont_ldst_elements(SVEContLdSt *info, target_ulong addr, uint64_t *vg, * Control the generation of page faults with @fault. Return false if * there is no work to do, which can only happen with @fault == FAULT_NO. */ -static bool __attribute__((unused)) -sve_cont_ldst_pages(SVEContLdSt *info, SVEContFault fault, CPUARMState *env, - target_ulong addr, MMUAccessType access_type, - uintptr_t retaddr) +static bool sve_cont_ldst_pages(SVEContLdSt *info, SVEContFault fault, + CPUARMState *env, target_ulong addr, + MMUAccessType access_type, uintptr_t retaddr) { int mmu_idx = cpu_mmu_index(env, false); int mem_off = info->mem_off_first[0]; @@ -4388,109 +4387,116 @@ static inline bool test_host_page(void *host) /* * Common helper for all contiguous one-register predicated loads. */ -static void sve_ld1_r(CPUARMState *env, void *vg, const target_ulong addr, - uint32_t desc, const uintptr_t retaddr, - const int esz, const int msz, - sve_ldst1_host_fn *host_fn, - sve_ldst1_tlb_fn *tlb_fn) +static inline QEMU_ALWAYS_INLINE +void sve_ld1_r(CPUARMState *env, uint64_t *vg, const target_ulong addr, + uint32_t desc, const uintptr_t retaddr, + const int esz, const int msz, + sve_ldst1_host_fn *host_fn, + sve_ldst1_tlb_fn *tlb_fn) { - const TCGMemOpIdx oi = extract32(desc, SIMD_DATA_SHIFT, MEMOPIDX_SHIFT); - const int mmu_idx = get_mmuidx(oi); const unsigned rd = extract32(desc, SIMD_DATA_SHIFT + MEMOPIDX_SHIFT, 5); void *vd = &env->vfp.zregs[rd]; - const int diffsz = esz - msz; const intptr_t reg_max = simd_oprsz(desc); - const intptr_t mem_max = reg_max >> diffsz; - ARMVectorReg scratch; + intptr_t reg_off, reg_last, mem_off; + SVEContLdSt info; void *host; - intptr_t split, reg_off, mem_off; + int flags; - /* Find the first active element. */ - reg_off = find_next_active(vg, 0, reg_max, esz); - if (unlikely(reg_off == reg_max)) { + /* Find the active elements. */ + if (!sve_cont_ldst_elements(&info, addr, vg, reg_max, esz, 1 << msz)) { /* The entire predicate was false; no load occurs. */ memset(vd, 0, reg_max); return; } - mem_off = reg_off >> diffsz; - /* - * If the (remaining) load is entirely within a single page, then: - * For softmmu, and the tlb hits, then no faults will occur; - * For user-only, either the first load will fault or none will. - * We can thus perform the load directly to the destination and - * Vd will be unmodified on any exception path. - */ - split = max_for_page(addr, mem_off, mem_max); - if (likely(split == mem_max)) { - host = tlb_vaddr_to_host(env, addr + mem_off, MMU_DATA_LOAD, mmu_idx); - if (test_host_page(host)) { - intptr_t i = reg_off; - host -= mem_off; - do { - host_fn(vd, i, host + (i >> diffsz)); - i = find_next_active(vg, i + (1 << esz), reg_max, esz); - } while (i < reg_max); - /* After having taken any fault, zero leading inactive elements. */ - swap_memzero(vd, reg_off); - return; - } - } + /* Probe the page(s). Exit with exception for any invalid page. */ + sve_cont_ldst_pages(&info, FAULT_ALL, env, addr, MMU_DATA_LOAD, retaddr); - /* - * Perform the predicated read into a temporary, thus ensuring - * if the load of the last element faults, Vd is not modified. - */ + flags = info.page[0].flags | info.page[1].flags; + if (unlikely(flags != 0)) { #ifdef CONFIG_USER_ONLY - swap_memzero(&scratch, reg_off); - host = g2h(addr); - do { - host_fn(&scratch, reg_off, host + (reg_off >> diffsz)); - reg_off += 1 << esz; - reg_off = find_next_active(vg, reg_off, reg_max, esz); - } while (reg_off < reg_max); + g_assert_not_reached(); #else - memset(&scratch, 0, reg_max); - goto start; - while (1) { - reg_off = find_next_active(vg, reg_off, reg_max, esz); - if (reg_off >= reg_max) { - break; - } - mem_off = reg_off >> diffsz; - split = max_for_page(addr, mem_off, mem_max); - - start: - if (split - mem_off >= (1 << msz)) { - /* At least one whole element on this page. */ - host = tlb_vaddr_to_host(env, addr + mem_off, - MMU_DATA_LOAD, mmu_idx); - if (host) { - host -= mem_off; - do { - host_fn(&scratch, reg_off, host + mem_off); - reg_off += 1 << esz; - reg_off = find_next_active(vg, reg_off, reg_max, esz); - mem_off = reg_off >> diffsz; - } while (split - mem_off >= (1 << msz)); - continue; + /* + * At least one page includes MMIO (or watchpoints). + * Any bus operation can fail with cpu_transaction_failed, + * which for ARM will raise SyncExternal. Perform the load + * into scratch memory to preserve register state until the end. + */ + ARMVectorReg scratch; + + memset(&scratch, 0, reg_max); + mem_off = info.mem_off_first[0]; + reg_off = info.reg_off_first[0]; + reg_last = info.reg_off_last[1]; + if (reg_last < 0) { + reg_last = info.reg_off_split; + if (reg_last < 0) { + reg_last = info.reg_off_last[0]; } } - /* - * Perform one normal read. This may fault, longjmping out to the - * main loop in order to raise an exception. It may succeed, and - * as a side-effect load the TLB entry for the next round. Finally, - * in the extremely unlikely case we're performing this operation - * on I/O memory, it may succeed but not bring in the TLB entry. - * But even then we have still made forward progress. - */ - tlb_fn(env, &scratch, reg_off, addr + mem_off, retaddr); - reg_off += 1 << esz; - } + do { + uint64_t pg = vg[reg_off >> 6]; + do { + if ((pg >> (reg_off & 63)) & 1) { + tlb_fn(env, &scratch, reg_off, addr + mem_off, retaddr); + } + reg_off += 1 << esz; + mem_off += 1 << msz; + } while (reg_off & 63); + } while (reg_off <= reg_last); + + memcpy(vd, &scratch, reg_max); + return; #endif + } + + /* The entire operation is in RAM, on valid pages. */ + + memset(vd, 0, reg_max); + mem_off = info.mem_off_first[0]; + reg_off = info.reg_off_first[0]; + reg_last = info.reg_off_last[0]; + host = info.page[0].host; - memcpy(vd, &scratch, reg_max); + while (reg_off <= reg_last) { + uint64_t pg = vg[reg_off >> 6]; + do { + if ((pg >> (reg_off & 63)) & 1) { + host_fn(vd, reg_off, host + mem_off); + } + reg_off += 1 << esz; + mem_off += 1 << msz; + } while (reg_off <= reg_last && (reg_off & 63)); + } + + /* + * Use the slow path to manage the cross-page misalignment. + * But we know this is RAM and cannot trap. + */ + mem_off = info.mem_off_split; + if (unlikely(mem_off >= 0)) { + tlb_fn(env, vd, info.reg_off_split, addr + mem_off, retaddr); + } + + mem_off = info.mem_off_first[1]; + if (unlikely(mem_off >= 0)) { + reg_off = info.reg_off_first[1]; + reg_last = info.reg_off_last[1]; + host = info.page[1].host; + + do { + uint64_t pg = vg[reg_off >> 6]; + do { + if ((pg >> (reg_off & 63)) & 1) { + host_fn(vd, reg_off, host + mem_off); + } + reg_off += 1 << esz; + mem_off += 1 << msz; + } while (reg_off & 63); + } while (reg_off <= reg_last); + } } #define DO_LD1_1(NAME, ESZ) \ -- 2.11.0