@@ -339,13 +339,13 @@
do { \
TCGv LSB = tcg_temp_local_new(); \
TCGLabel *label = gen_new_label(); \
- GET_EA; \
+ tcg_gen_movi_tl(EA, 0); \
PRED; \
+ CHECK_NOSHUF_PRED(GET_EA, SIZE, LSB); \
PRED_LOAD_CANCEL(LSB, EA); \
tcg_gen_movi_tl(RdV, 0); \
- CHECK_NOSHUF; \
tcg_gen_brcondi_tl(TCG_COND_EQ, LSB, 0, label); \
- fLOAD(1, SIZE, SIGN, EA, RdV); \
+ fLOAD(1, SIZE, SIGN, EA, RdV); \
gen_set_label(label); \
tcg_temp_free(LSB); \
} while (0)
@@ -399,13 +399,13 @@
do { \
TCGv LSB = tcg_temp_local_new(); \
TCGLabel *label = gen_new_label(); \
- GET_EA; \
+ tcg_gen_movi_tl(EA, 0); \
PRED; \
+ CHECK_NOSHUF_PRED(GET_EA, 8, LSB); \
PRED_LOAD_CANCEL(LSB, EA); \
tcg_gen_movi_i64(RddV, 0); \
- CHECK_NOSHUF; \
tcg_gen_brcondi_tl(TCG_COND_EQ, LSB, 0, label); \
- fLOAD(1, 8, u, EA, RddV); \
+ fLOAD(1, 8, u, EA, RddV); \
gen_set_label(label); \
tcg_temp_free(LSB); \
} while (0)
@@ -104,6 +104,7 @@ DEF_HELPER_1(vwhist128q, void, env)
DEF_HELPER_2(vwhist128m, void, env, s32)
DEF_HELPER_2(vwhist128qm, void, env, s32)
+DEF_HELPER_4(probe_noshuf_load, void, env, i32, int, int)
DEF_HELPER_2(probe_pkt_scalar_store_s0, void, env, int)
DEF_HELPER_2(probe_hvx_stores, void, env, int)
DEF_HELPER_3(probe_pkt_scalar_hvx_stores, void, env, int, int)
@@ -87,11 +87,28 @@
*
*
* For qemu, we look for a load in slot 0 when there is a store in slot 1
- * in the same packet. When we see this, we call a helper that merges the
- * bytes from the store buffer with the value loaded from memory.
+ * in the same packet. When we see this, we call a helper that probes the
+ * load to make sure it doesn't fault. Then, we process the store ahead of
+ * the actual load.
+
*/
-#define CHECK_NOSHUF \
+#define CHECK_NOSHUF(VA, SIZE) \
do { \
+ if (insn->slot == 0 && pkt->pkt_has_store_s1) { \
+ probe_noshuf_load(VA, SIZE, ctx->mem_idx); \
+ process_store(ctx, pkt, 1); \
+ } \
+ } while (0)
+
+#define CHECK_NOSHUF_PRED(GET_EA, SIZE, PRED) \
+ do { \
+ TCGLabel *label = gen_new_label(); \
+ tcg_gen_brcondi_tl(TCG_COND_EQ, PRED, 0, label); \
+ GET_EA; \
+ if (insn->slot == 0 && pkt->pkt_has_store_s1) { \
+ probe_noshuf_load(EA, SIZE, ctx->mem_idx); \
+ } \
+ gen_set_label(label); \
if (insn->slot == 0 && pkt->pkt_has_store_s1) { \
process_store(ctx, pkt, 1); \
} \
@@ -99,37 +116,37 @@
#define MEM_LOAD1s(DST, VA) \
do { \
- CHECK_NOSHUF; \
+ CHECK_NOSHUF(VA, 1); \
tcg_gen_qemu_ld8s(DST, VA, ctx->mem_idx); \
} while (0)
#define MEM_LOAD1u(DST, VA) \
do { \
- CHECK_NOSHUF; \
+ CHECK_NOSHUF(VA, 1); \
tcg_gen_qemu_ld8u(DST, VA, ctx->mem_idx); \
} while (0)
#define MEM_LOAD2s(DST, VA) \
do { \
- CHECK_NOSHUF; \
+ CHECK_NOSHUF(VA, 2); \
tcg_gen_qemu_ld16s(DST, VA, ctx->mem_idx); \
} while (0)
#define MEM_LOAD2u(DST, VA) \
do { \
- CHECK_NOSHUF; \
+ CHECK_NOSHUF(VA, 2); \
tcg_gen_qemu_ld16u(DST, VA, ctx->mem_idx); \
} while (0)
#define MEM_LOAD4s(DST, VA) \
do { \
- CHECK_NOSHUF; \
+ CHECK_NOSHUF(VA, 4); \
tcg_gen_qemu_ld32s(DST, VA, ctx->mem_idx); \
} while (0)
#define MEM_LOAD4u(DST, VA) \
do { \
- CHECK_NOSHUF; \
+ CHECK_NOSHUF(VA, 4); \
tcg_gen_qemu_ld32s(DST, VA, ctx->mem_idx); \
} while (0)
#define MEM_LOAD8u(DST, VA) \
do { \
- CHECK_NOSHUF; \
+ CHECK_NOSHUF(VA, 8); \
tcg_gen_qemu_ld64(DST, VA, ctx->mem_idx); \
} while (0)
@@ -638,5 +638,12 @@ static void vec_to_qvec(size_t size, intptr_t dstoff, intptr_t srcoff)
tcg_temp_free_i64(mask);
}
+static void probe_noshuf_load(TCGv va, int s, int mi)
+{
+ TCGv size = tcg_constant_tl(s);
+ TCGv mem_idx = tcg_constant_tl(mi);
+ gen_helper_probe_noshuf_load(cpu_env, va, size, mem_idx);
+}
+
#include "tcg_funcs_generated.c.inc"
#include "tcg_func_table_generated.c.inc"
@@ -442,6 +442,17 @@ static void probe_store(CPUHexagonState *env, int slot, int mmu_idx)
}
}
+/*
+ * Called from a mem_noshuf packet to make sure the load doesn't
+ * raise an exception
+ */
+void HELPER(probe_noshuf_load)(CPUHexagonState *env, target_ulong va,
+ int size, int mmu_idx)
+{
+ uintptr_t retaddr = GETPC();
+ probe_read(env, va, size, mmu_idx, retaddr);
+}
+
/* Called during packet commit when there are two scalar stores */
void HELPER(probe_pkt_scalar_store_s0)(CPUHexagonState *env, int mmu_idx)
{
@@ -514,10 +525,12 @@ void HELPER(probe_pkt_scalar_hvx_stores)(CPUHexagonState *env, int mask,
* If the load is in slot 0 and there is a store in slot1 (that
* wasn't cancelled), we have to do the store first.
*/
-static void check_noshuf(CPUHexagonState *env, uint32_t slot)
+static void check_noshuf(CPUHexagonState *env, uint32_t slot,
+ target_ulong vaddr, int size)
{
if (slot == 0 && env->pkt_has_store_s1 &&
((env->slot_cancelled & (1 << 1)) == 0)) {
+ HELPER(probe_noshuf_load)(env, vaddr, size, MMU_USER_IDX);
HELPER(commit_store)(env, 1);
}
}
@@ -526,7 +539,7 @@ static uint8_t mem_load1(CPUHexagonState *env, uint32_t slot,
target_ulong vaddr)
{
uintptr_t ra = GETPC();
- check_noshuf(env, slot);
+ check_noshuf(env, slot, vaddr, 1);
return cpu_ldub_data_ra(env, vaddr, ra);
}
@@ -534,7 +547,7 @@ static uint16_t mem_load2(CPUHexagonState *env, uint32_t slot,
target_ulong vaddr)
{
uintptr_t ra = GETPC();
- check_noshuf(env, slot);
+ check_noshuf(env, slot, vaddr, 2);
return cpu_lduw_data_ra(env, vaddr, ra);
}
@@ -542,7 +555,7 @@ static uint32_t mem_load4(CPUHexagonState *env, uint32_t slot,
target_ulong vaddr)
{
uintptr_t ra = GETPC();
- check_noshuf(env, slot);
+ check_noshuf(env, slot, vaddr, 4);
return cpu_ldl_data_ra(env, vaddr, ra);
}
@@ -550,7 +563,7 @@ static uint64_t mem_load8(CPUHexagonState *env, uint32_t slot,
target_ulong vaddr)
{
uintptr_t ra = GETPC();
- check_noshuf(env, slot);
+ check_noshuf(env, slot, vaddr, 8);
return cpu_ldq_data_ra(env, vaddr, ra);
}
new file mode 100644
@@ -0,0 +1,146 @@
+/*
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * Test the VLIW semantics of exceptions with mem_noshuf
+ *
+ * When a packet has the :mem_noshuf attribute, the semantics dictate
+ * That the load will get the data from the store if the addresses overlap.
+ * To accomplish this, we perform the store first. However, we have to
+ * handle the case where the store raises an exception. In that case, the
+ * store should not alter the machine state.
+ *
+ * We test this with a mem_noshuf packet with a store to a global variable,
+ * "should_not_change" and a load from NULL. After the SIGSEGV is caught,
+ * we check * that the "should_not_change" value is the same.
+ *
+ * We also check that a predicated load where the predicate is false doesn't
+ * raise an exception and allows the store to happen.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <setjmp.h>
+#include <signal.h>
+
+int err;
+int segv_caught;
+
+#define SHOULD_NOT_CHANGE_VAL 5
+int should_not_change = SHOULD_NOT_CHANGE_VAL;
+
+#define OK_TO_CHANGE_VAL 13
+int ok_to_change = OK_TO_CHANGE_VAL;
+
+static void __check(const char *filename, int line, int x, int expect)
+{
+ if (x != expect) {
+ printf("ERROR %s:%d - %d != %d\n",
+ filename, line, x, expect);
+ err++;
+ }
+}
+
+#define check(x, expect) __check(__FILE__, __LINE__, (x), (expect))
+
+static void __chk_error(const char *filename, int line, int ret)
+{
+ if (ret < 0) {
+ printf("ERROR %s:%d - %d\n", filename, line, ret);
+ err++;
+ }
+}
+
+#define chk_error(ret) __chk_error(__FILE__, __LINE__, (ret))
+
+jmp_buf jmp_env;
+
+static void sig_segv(int sig, siginfo_t *info, void *puc)
+{
+ check(sig, SIGSEGV);
+ segv_caught = 1;
+ longjmp(jmp_env, 1);
+}
+
+int main()
+{
+ struct sigaction act;
+ int dummy32;
+ long long dummy64;
+ void *p;
+
+ /* SIGSEGV test */
+ act.sa_sigaction = sig_segv;
+ sigemptyset(&act.sa_mask);
+ act.sa_flags = SA_SIGINFO;
+ chk_error(sigaction(SIGSEGV, &act, NULL));
+ if (setjmp(jmp_env) == 0) {
+ asm volatile("r18 = ##should_not_change\n\t"
+ "r19 = #0\n\t"
+ "{\n\t"
+ " memw(r18) = #7\n\t"
+ " %0 = memw(r19)\n\t"
+ "}:mem_noshuf\n\t"
+ : "=r"(dummy32) : : "r18", "r19", "memory");
+ }
+
+ act.sa_handler = SIG_DFL;
+ sigemptyset(&act.sa_mask);
+ act.sa_flags = 0;
+ chk_error(sigaction(SIGSEGV, &act, NULL));
+
+ check(segv_caught, 1);
+ check(should_not_change, SHOULD_NOT_CHANGE_VAL);
+
+ /*
+ * Check that a predicated load where the predicate is false doesn't
+ * raise an exception and allows the store to happen.
+ */
+ asm volatile("r18 = ##ok_to_change\n\t"
+ "r19 = #0\n\t"
+ "p0 = cmp.gt(r0, r0)\n\t"
+ "{\n\t"
+ " memw(r18) = #7\n\t"
+ " if (p0) %0 = memw(r19)\n\t"
+ "}:mem_noshuf\n\t"
+ : "=r"(dummy32) : : "r18", "r19", "p0", "memory");
+
+ check(ok_to_change, 7);
+
+ /*
+ * Also check that the post-increment doesn't happen when the
+ * predicate is false.
+ */
+ ok_to_change = OK_TO_CHANGE_VAL;
+ p = NULL;
+ asm volatile("r18 = ##ok_to_change\n\t"
+ "p0 = cmp.gt(r0, r0)\n\t"
+ "{\n\t"
+ " memw(r18) = #9\n\t"
+ " if (p0) %1 = memd(%0 ++ #8)\n\t"
+ "}:mem_noshuf\n\t"
+ : "+r"(p), "=r"(dummy64) : : "r18", "p0", "memory");
+
+ check(ok_to_change, 9);
+ check((int)p, (int)NULL);
+
+ puts(err ? "FAIL" : "PASS");
+ return err ? EXIT_FAILURE : EXIT_SUCCESS;
+}
@@ -35,6 +35,7 @@ HEX_TESTS += preg_alias
HEX_TESTS += dual_stores
HEX_TESTS += multi_result
HEX_TESTS += mem_noshuf
+HEX_TESTS += mem_noshuf_exception
HEX_TESTS += circ
HEX_TESTS += brev
HEX_TESTS += load_unpack