[Qemu-devel] [PATCH 3/3] target-mips: Misaligned Memory Accesses for MSA

[Yongbok Kim]

MIPS SIMD Architecture vector loads and stores require misalignment support.
MSA Memory access should work as an atomic operation. Therefore, it has to
check validity of all the addresses for the operation.

Signed-off-by: Yongbok Kim <address@hidden>
---
 target-mips/op_helper.c |   30 ++++++++++++++++++++++++++++++
 1 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/target-mips/op_helper.c b/target-mips/op_helper.c
index dacc92b..89a7de6 100644
--- a/target-mips/op_helper.c
+++ b/target-mips/op_helper.c
@@ -3571,6 +3571,24 @@ FOP_CONDN_S(sne,  (float32_lt(fst1, fst0, 
&env->active_fpu.fp_status)
 /* Element-by-element access macros */
 #define DF_ELEMENTS(df) (MSA_WRLEN / DF_BITS(df))
 
+#if !defined(CONFIG_USER_ONLY)
+static bool cpu_mips_validate_msa_block_access(CPUMIPSState *env,
+                                        target_ulong address, int df, int rw)
+{
+    int i;
+    for (i = 0; i < DF_ELEMENTS(df); i++) {
+        if (!cpu_mips_validate_access(env, address + (i << df),
+            address, (1 << df), rw)) {
+            CPUState *cs = CPU(mips_env_get_cpu(env));
+            helper_raise_exception_err(env, cs->exception_index,
+                                       env->error_code);
+            return false;
+        }
+    }
+    return true;
+}
+#endif
+
 void helper_msa_ld_df(CPUMIPSState *env, uint32_t df, uint32_t wd, uint32_t rs,
                      int32_t s10)
 {
@@ -3578,6 +3596,12 @@ void helper_msa_ld_df(CPUMIPSState *env, uint32_t df, 
uint32_t wd, uint32_t rs,
     target_ulong addr = env->active_tc.gpr[rs] + (s10 << df);
     int i;
 
+#if !defined(CONFIG_USER_ONLY)
+    if (!cpu_mips_validate_msa_block_access(env, addr, df, MMU_DATA_LOAD)) {
+        return;
+    }
+#endif
+
     switch (df) {
     case DF_BYTE:
         for (i = 0; i < DF_ELEMENTS(DF_BYTE); i++) {
@@ -3613,6 +3637,12 @@ void helper_msa_st_df(CPUMIPSState *env, uint32_t df, 
uint32_t wd, uint32_t rs,
     target_ulong addr = env->active_tc.gpr[rs] + (s10 << df);
     int i;
 
+#if !defined(CONFIG_USER_ONLY)
+    if (!cpu_mips_validate_msa_block_access(env, addr, df, MMU_DATA_STORE)) {
+        return;
+    }
+#endif
+
     switch (df) {
     case DF_BYTE:
         for (i = 0; i < DF_ELEMENTS(DF_BYTE); i++) {
-- 
1.7.5.4