[PULL 23/34] target/arm: Reuse sve_probe_page for gather first-fault loads

[Peter Maydell <peter.maydell@linaro.org>]

From: Richard Henderson <richard.henderson@linaro.org>

This avoids the need for a separate set of helpers to implement
no-fault semantics, and will enable MTE in the future.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200508154359.7494-17-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/sve_helper.c | 323 ++++++++++++++++------------------------
 1 file changed, 127 insertions(+), 196 deletions(-)

diff --git a/target/arm/sve_helper.c b/target/arm/sve_helper.c
index 4ed9bbe1ee0..1560129b080 100644
--- a/target/arm/sve_helper.c
+++ b/target/arm/sve_helper.c
@@ -5254,231 +5254,162 @@ DO_LD1_ZPZ_D(dd_be, zd)
 
 /* First fault loads with a vector index.  */
 
-/* Load one element into VD+REG_OFF from (ENV,VADDR) without faulting.
- * The controlling predicate is known to be true.  Return true if the
- * load was successful.
- */
-typedef bool sve_ld1_nf_fn(CPUARMState *env, void *vd, intptr_t reg_off,
-                           target_ulong vaddr, int mmu_idx);
-
-#ifdef CONFIG_SOFTMMU
-#define DO_LD_NF(NAME, H, TYPEE, TYPEM, HOST) \
-static bool sve_ld##NAME##_nf(CPUARMState *env, void *vd, intptr_t reg_off, \
-                              target_ulong addr, int mmu_idx)               \
-{                                                                           \
-    target_ulong next_page = -(addr | TARGET_PAGE_MASK);                    \
-    if (likely(next_page - addr >= sizeof(TYPEM))) {                        \
-        void *host = tlb_vaddr_to_host(env, addr, MMU_DATA_LOAD, mmu_idx);  \
-        if (likely(host)) {                                                 \
-            TYPEM val = HOST(host);                                         \
-            *(TYPEE *)(vd + H(reg_off)) = val;                              \
-            return true;                                                    \
-        }                                                                   \
-    }                                                                       \
-    return false;                                                           \
-}
-#else
-#define DO_LD_NF(NAME, H, TYPEE, TYPEM, HOST) \
-static bool sve_ld##NAME##_nf(CPUARMState *env, void *vd, intptr_t reg_off, \
-                            target_ulong addr, int mmu_idx)                 \
-{                                                                           \
-    if (likely(page_check_range(addr, sizeof(TYPEM), PAGE_READ))) {         \
-        TYPEM val = HOST(g2h(addr));                                        \
-        *(TYPEE *)(vd + H(reg_off)) = val;                                  \
-        return true;                                                        \
-    }                                                                       \
-    return false;                                                           \
-}
-#endif
-
-DO_LD_NF(bsu, H1_4, uint32_t, uint8_t, ldub_p)
-DO_LD_NF(bss, H1_4, uint32_t,  int8_t, ldsb_p)
-DO_LD_NF(bdu,     , uint64_t, uint8_t, ldub_p)
-DO_LD_NF(bds,     , uint64_t,  int8_t, ldsb_p)
-
-DO_LD_NF(hsu_le, H1_4, uint32_t, uint16_t, lduw_le_p)
-DO_LD_NF(hss_le, H1_4, uint32_t,  int16_t, ldsw_le_p)
-DO_LD_NF(hsu_be, H1_4, uint32_t, uint16_t, lduw_be_p)
-DO_LD_NF(hss_be, H1_4, uint32_t,  int16_t, ldsw_be_p)
-DO_LD_NF(hdu_le,     , uint64_t, uint16_t, lduw_le_p)
-DO_LD_NF(hds_le,     , uint64_t,  int16_t, ldsw_le_p)
-DO_LD_NF(hdu_be,     , uint64_t, uint16_t, lduw_be_p)
-DO_LD_NF(hds_be,     , uint64_t,  int16_t, ldsw_be_p)
-
-DO_LD_NF(ss_le,  H1_4, uint32_t, uint32_t, ldl_le_p)
-DO_LD_NF(ss_be,  H1_4, uint32_t, uint32_t, ldl_be_p)
-DO_LD_NF(sdu_le,     , uint64_t, uint32_t, ldl_le_p)
-DO_LD_NF(sds_le,     , uint64_t,  int32_t, ldl_le_p)
-DO_LD_NF(sdu_be,     , uint64_t, uint32_t, ldl_be_p)
-DO_LD_NF(sds_be,     , uint64_t,  int32_t, ldl_be_p)
-
-DO_LD_NF(dd_le,      , uint64_t, uint64_t, ldq_le_p)
-DO_LD_NF(dd_be,      , uint64_t, uint64_t, ldq_be_p)
-
 /*
- * Common helper for all gather first-faulting loads.
+ * Common helpers for all gather first-faulting loads.
  */
-static inline void sve_ldff1_zs(CPUARMState *env, void *vd, void *vg, void *vm,
-                                target_ulong base, uint32_t desc, uintptr_t ra,
-                                zreg_off_fn *off_fn, sve_ldst1_tlb_fn *tlb_fn,
-                                sve_ld1_nf_fn *nonfault_fn)
+
+static inline QEMU_ALWAYS_INLINE
+void sve_ldff1_z(CPUARMState *env, void *vd, uint64_t *vg, void *vm,
+                 target_ulong base, uint32_t desc, uintptr_t retaddr,
+                 const int esz, const int msz, zreg_off_fn *off_fn,
+                 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 int mmu_idx = cpu_mmu_index(env, false);
     const int scale = extract32(desc, SIMD_DATA_SHIFT + MEMOPIDX_SHIFT, 2);
-    intptr_t reg_off, reg_max = simd_oprsz(desc);
-    target_ulong addr;
+    const int esize = 1 << esz;
+    const int msize = 1 << msz;
+    const intptr_t reg_max = simd_oprsz(desc);
+    intptr_t reg_off;
+    SVEHostPage info;
+    target_ulong addr, in_page;
 
     /* Skip to the first true predicate.  */
-    reg_off = find_next_active(vg, 0, reg_max, MO_32);
-    if (likely(reg_off < reg_max)) {
-        /* Perform one normal read, which will fault or not.  */
-        addr = off_fn(vm, reg_off);
-        addr = base + (addr << scale);
-        tlb_fn(env, vd, reg_off, addr, ra);
-
-        /* The rest of the reads will be non-faulting.  */
+    reg_off = find_next_active(vg, 0, reg_max, esz);
+    if (unlikely(reg_off >= reg_max)) {
+        /* The entire predicate was false; no load occurs.  */
+        memset(vd, 0, reg_max);
+        return;
     }
 
-    /* After any fault, zero the leading predicated false elements.  */
+    /*
+     * Probe the first element, allowing faults.
+     */
+    addr = base + (off_fn(vm, reg_off) << scale);
+    tlb_fn(env, vd, reg_off, addr, retaddr);
+
+    /* After any fault, zero the other elements. */
     swap_memzero(vd, reg_off);
+    reg_off += esize;
+    swap_memzero(vd + reg_off, reg_max - reg_off);
 
-    while (likely((reg_off += 4) < reg_max)) {
-        uint64_t pg = *(uint64_t *)(vg + (reg_off >> 6) * 8);
-        if (likely((pg >> (reg_off & 63)) & 1)) {
-            addr = off_fn(vm, reg_off);
-            addr = base + (addr << scale);
-            if (!nonfault_fn(env, vd, reg_off, addr, mmu_idx)) {
-                record_fault(env, reg_off, reg_max);
-                break;
+    /*
+     * Probe the remaining elements, not allowing faults.
+     */
+    while (reg_off < reg_max) {
+        uint64_t pg = vg[reg_off >> 6];
+        do {
+            if (likely((pg >> (reg_off & 63)) & 1)) {
+                addr = base + (off_fn(vm, reg_off) << scale);
+                in_page = -(addr | TARGET_PAGE_MASK);
+
+                if (unlikely(in_page < msize)) {
+                    /* Stop if the element crosses a page boundary. */
+                    goto fault;
+                }
+
+                sve_probe_page(&info, true, env, addr, 0, MMU_DATA_LOAD,
+                               mmu_idx, retaddr);
+                if (unlikely(info.flags & (TLB_INVALID_MASK | TLB_MMIO))) {
+                    goto fault;
+                }
+                if (unlikely(info.flags & TLB_WATCHPOINT) &&
+                    (cpu_watchpoint_address_matches
+                     (env_cpu(env), addr, msize) & BP_MEM_READ)) {
+                    goto fault;
+                }
+                /* TODO: MTE check. */
+
+                host_fn(vd, reg_off, info.host);
             }
-        } else {
-            *(uint32_t *)(vd + H1_4(reg_off)) = 0;
-        }
+            reg_off += esize;
+        } while (reg_off & 63);
     }
+    return;
+
+ fault:
+    record_fault(env, reg_off, reg_max);
 }
 
-static inline void sve_ldff1_zd(CPUARMState *env, void *vd, void *vg, void *vm,
-                                target_ulong base, uint32_t desc, uintptr_t ra,
-                                zreg_off_fn *off_fn, sve_ldst1_tlb_fn *tlb_fn,
-                                sve_ld1_nf_fn *nonfault_fn)
-{
-    const TCGMemOpIdx oi = extract32(desc, SIMD_DATA_SHIFT, MEMOPIDX_SHIFT);
-    const int mmu_idx = get_mmuidx(oi);
-    const int scale = extract32(desc, SIMD_DATA_SHIFT + MEMOPIDX_SHIFT, 2);
-    intptr_t reg_off, reg_max = simd_oprsz(desc);
-    target_ulong addr;
-
-    /* Skip to the first true predicate.  */
-    reg_off = find_next_active(vg, 0, reg_max, MO_64);
-    if (likely(reg_off < reg_max)) {
-        /* Perform one normal read, which will fault or not.  */
-        addr = off_fn(vm, reg_off);
-        addr = base + (addr << scale);
-        tlb_fn(env, vd, reg_off, addr, ra);
-
-        /* The rest of the reads will be non-faulting.  */
-    }
-
-    /* After any fault, zero the leading predicated false elements.  */
-    swap_memzero(vd, reg_off);
-
-    while (likely((reg_off += 8) < reg_max)) {
-        uint8_t pg = *(uint8_t *)(vg + H1(reg_off >> 3));
-        if (likely(pg & 1)) {
-            addr = off_fn(vm, reg_off);
-            addr = base + (addr << scale);
-            if (!nonfault_fn(env, vd, reg_off, addr, mmu_idx)) {
-                record_fault(env, reg_off, reg_max);
-                break;
-            }
-        } else {
-            *(uint64_t *)(vd + reg_off) = 0;
-        }
-    }
+#define DO_LDFF1_ZPZ_S(MEM, OFS, MSZ) \
+void HELPER(sve_ldff##MEM##_##OFS)(CPUARMState *env, void *vd, void *vg,       \
+                                   void *vm, target_ulong base, uint32_t desc) \
+{                                                                              \
+    sve_ldff1_z(env, vd, vg, vm, base, desc, GETPC(), MO_32, MSZ,              \
+                off_##OFS##_s, sve_ld1##MEM##_host, sve_ld1##MEM##_tlb);       \
 }
 
-#define DO_LDFF1_ZPZ_S(MEM, OFS) \
-void HELPER(sve_ldff##MEM##_##OFS)                                      \
-    (CPUARMState *env, void *vd, void *vg, void *vm,                    \
-     target_ulong base, uint32_t desc)                                  \
-{                                                                       \
-    sve_ldff1_zs(env, vd, vg, vm, base, desc, GETPC(),                  \
-                 off_##OFS##_s, sve_ld1##MEM##_tlb, sve_ld##MEM##_nf);  \
+#define DO_LDFF1_ZPZ_D(MEM, OFS, MSZ) \
+void HELPER(sve_ldff##MEM##_##OFS)(CPUARMState *env, void *vd, void *vg,       \
+                                   void *vm, target_ulong base, uint32_t desc) \
+{                                                                              \
+    sve_ldff1_z(env, vd, vg, vm, base, desc, GETPC(), MO_64, MSZ,              \
+                off_##OFS##_d, sve_ld1##MEM##_host, sve_ld1##MEM##_tlb);       \
 }
 
-#define DO_LDFF1_ZPZ_D(MEM, OFS) \
-void HELPER(sve_ldff##MEM##_##OFS)                                      \
-    (CPUARMState *env, void *vd, void *vg, void *vm,                    \
-     target_ulong base, uint32_t desc)                                  \
-{                                                                       \
-    sve_ldff1_zd(env, vd, vg, vm, base, desc, GETPC(),                  \
-                 off_##OFS##_d, sve_ld1##MEM##_tlb, sve_ld##MEM##_nf);  \
-}
+DO_LDFF1_ZPZ_S(bsu, zsu, MO_8)
+DO_LDFF1_ZPZ_S(bsu, zss, MO_8)
+DO_LDFF1_ZPZ_D(bdu, zsu, MO_8)
+DO_LDFF1_ZPZ_D(bdu, zss, MO_8)
+DO_LDFF1_ZPZ_D(bdu, zd, MO_8)
 
-DO_LDFF1_ZPZ_S(bsu, zsu)
-DO_LDFF1_ZPZ_S(bsu, zss)
-DO_LDFF1_ZPZ_D(bdu, zsu)
-DO_LDFF1_ZPZ_D(bdu, zss)
-DO_LDFF1_ZPZ_D(bdu, zd)
+DO_LDFF1_ZPZ_S(bss, zsu, MO_8)
+DO_LDFF1_ZPZ_S(bss, zss, MO_8)
+DO_LDFF1_ZPZ_D(bds, zsu, MO_8)
+DO_LDFF1_ZPZ_D(bds, zss, MO_8)
+DO_LDFF1_ZPZ_D(bds, zd, MO_8)
 
-DO_LDFF1_ZPZ_S(bss, zsu)
-DO_LDFF1_ZPZ_S(bss, zss)
-DO_LDFF1_ZPZ_D(bds, zsu)
-DO_LDFF1_ZPZ_D(bds, zss)
-DO_LDFF1_ZPZ_D(bds, zd)
+DO_LDFF1_ZPZ_S(hsu_le, zsu, MO_16)
+DO_LDFF1_ZPZ_S(hsu_le, zss, MO_16)
+DO_LDFF1_ZPZ_D(hdu_le, zsu, MO_16)
+DO_LDFF1_ZPZ_D(hdu_le, zss, MO_16)
+DO_LDFF1_ZPZ_D(hdu_le, zd, MO_16)
 
-DO_LDFF1_ZPZ_S(hsu_le, zsu)
-DO_LDFF1_ZPZ_S(hsu_le, zss)
-DO_LDFF1_ZPZ_D(hdu_le, zsu)
-DO_LDFF1_ZPZ_D(hdu_le, zss)
-DO_LDFF1_ZPZ_D(hdu_le, zd)
+DO_LDFF1_ZPZ_S(hsu_be, zsu, MO_16)
+DO_LDFF1_ZPZ_S(hsu_be, zss, MO_16)
+DO_LDFF1_ZPZ_D(hdu_be, zsu, MO_16)
+DO_LDFF1_ZPZ_D(hdu_be, zss, MO_16)
+DO_LDFF1_ZPZ_D(hdu_be, zd, MO_16)
 
-DO_LDFF1_ZPZ_S(hsu_be, zsu)
-DO_LDFF1_ZPZ_S(hsu_be, zss)
-DO_LDFF1_ZPZ_D(hdu_be, zsu)
-DO_LDFF1_ZPZ_D(hdu_be, zss)
-DO_LDFF1_ZPZ_D(hdu_be, zd)
+DO_LDFF1_ZPZ_S(hss_le, zsu, MO_16)
+DO_LDFF1_ZPZ_S(hss_le, zss, MO_16)
+DO_LDFF1_ZPZ_D(hds_le, zsu, MO_16)
+DO_LDFF1_ZPZ_D(hds_le, zss, MO_16)
+DO_LDFF1_ZPZ_D(hds_le, zd, MO_16)
 
-DO_LDFF1_ZPZ_S(hss_le, zsu)
-DO_LDFF1_ZPZ_S(hss_le, zss)
-DO_LDFF1_ZPZ_D(hds_le, zsu)
-DO_LDFF1_ZPZ_D(hds_le, zss)
-DO_LDFF1_ZPZ_D(hds_le, zd)
+DO_LDFF1_ZPZ_S(hss_be, zsu, MO_16)
+DO_LDFF1_ZPZ_S(hss_be, zss, MO_16)
+DO_LDFF1_ZPZ_D(hds_be, zsu, MO_16)
+DO_LDFF1_ZPZ_D(hds_be, zss, MO_16)
+DO_LDFF1_ZPZ_D(hds_be, zd, MO_16)
 
-DO_LDFF1_ZPZ_S(hss_be, zsu)
-DO_LDFF1_ZPZ_S(hss_be, zss)
-DO_LDFF1_ZPZ_D(hds_be, zsu)
-DO_LDFF1_ZPZ_D(hds_be, zss)
-DO_LDFF1_ZPZ_D(hds_be, zd)
+DO_LDFF1_ZPZ_S(ss_le,  zsu, MO_32)
+DO_LDFF1_ZPZ_S(ss_le,  zss, MO_32)
+DO_LDFF1_ZPZ_D(sdu_le, zsu, MO_32)
+DO_LDFF1_ZPZ_D(sdu_le, zss, MO_32)
+DO_LDFF1_ZPZ_D(sdu_le, zd, MO_32)
 
-DO_LDFF1_ZPZ_S(ss_le,  zsu)
-DO_LDFF1_ZPZ_S(ss_le,  zss)
-DO_LDFF1_ZPZ_D(sdu_le, zsu)
-DO_LDFF1_ZPZ_D(sdu_le, zss)
-DO_LDFF1_ZPZ_D(sdu_le, zd)
+DO_LDFF1_ZPZ_S(ss_be,  zsu, MO_32)
+DO_LDFF1_ZPZ_S(ss_be,  zss, MO_32)
+DO_LDFF1_ZPZ_D(sdu_be, zsu, MO_32)
+DO_LDFF1_ZPZ_D(sdu_be, zss, MO_32)
+DO_LDFF1_ZPZ_D(sdu_be, zd, MO_32)
 
-DO_LDFF1_ZPZ_S(ss_be,  zsu)
-DO_LDFF1_ZPZ_S(ss_be,  zss)
-DO_LDFF1_ZPZ_D(sdu_be, zsu)
-DO_LDFF1_ZPZ_D(sdu_be, zss)
-DO_LDFF1_ZPZ_D(sdu_be, zd)
+DO_LDFF1_ZPZ_D(sds_le, zsu, MO_32)
+DO_LDFF1_ZPZ_D(sds_le, zss, MO_32)
+DO_LDFF1_ZPZ_D(sds_le, zd, MO_32)
 
-DO_LDFF1_ZPZ_D(sds_le, zsu)
-DO_LDFF1_ZPZ_D(sds_le, zss)
-DO_LDFF1_ZPZ_D(sds_le, zd)
+DO_LDFF1_ZPZ_D(sds_be, zsu, MO_32)
+DO_LDFF1_ZPZ_D(sds_be, zss, MO_32)
+DO_LDFF1_ZPZ_D(sds_be, zd, MO_32)
 
-DO_LDFF1_ZPZ_D(sds_be, zsu)
-DO_LDFF1_ZPZ_D(sds_be, zss)
-DO_LDFF1_ZPZ_D(sds_be, zd)
+DO_LDFF1_ZPZ_D(dd_le, zsu, MO_64)
+DO_LDFF1_ZPZ_D(dd_le, zss, MO_64)
+DO_LDFF1_ZPZ_D(dd_le, zd, MO_64)
 
-DO_LDFF1_ZPZ_D(dd_le, zsu)
-DO_LDFF1_ZPZ_D(dd_le, zss)
-DO_LDFF1_ZPZ_D(dd_le, zd)
-
-DO_LDFF1_ZPZ_D(dd_be, zsu)
-DO_LDFF1_ZPZ_D(dd_be, zss)
-DO_LDFF1_ZPZ_D(dd_be, zd)
+DO_LDFF1_ZPZ_D(dd_be, zsu, MO_64)
+DO_LDFF1_ZPZ_D(dd_be, zss, MO_64)
+DO_LDFF1_ZPZ_D(dd_be, zd, MO_64)
 
 /* Stores with a vector index.  */
 
-- 
2.20.1