[Qemu-devel] [PULL 06/21] target/arm: Use pointers in neon tbl helper

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

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

Rather than passing a regno to the helper, pass pointers to the
vector register directly.  This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180119045438.28582-5-richard.henderson@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/helper.h    |  2 +-
 target/arm/op_helper.c | 17 +++++++----------
 target/arm/translate.c |  8 ++++----
 3 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/target/arm/helper.h b/target/arm/helper.h
index dbdc38f..5dec2e6 100644
--- a/target/arm/helper.h
+++ b/target/arm/helper.h
@@ -188,7 +188,7 @@ DEF_HELPER_FLAGS_2(rsqrte_f32, TCG_CALL_NO_RWG, f32, f32, ptr)
 DEF_HELPER_FLAGS_2(rsqrte_f64, TCG_CALL_NO_RWG, f64, f64, ptr)
 DEF_HELPER_2(recpe_u32, i32, i32, ptr)
 DEF_HELPER_FLAGS_2(rsqrte_u32, TCG_CALL_NO_RWG, i32, i32, ptr)
-DEF_HELPER_5(neon_tbl, i32, env, i32, i32, i32, i32)
+DEF_HELPER_FLAGS_4(neon_tbl, TCG_CALL_NO_RWG, i32, i32, i32, ptr, i32)
 
 DEF_HELPER_3(shl_cc, i32, env, i32, i32)
 DEF_HELPER_3(shr_cc, i32, env, i32, i32)
diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
index 712c5c5..a937e76 100644
--- a/target/arm/op_helper.c
+++ b/target/arm/op_helper.c
@@ -54,20 +54,17 @@ static int exception_target_el(CPUARMState *env)
     return target_el;
 }
 
-uint32_t HELPER(neon_tbl)(CPUARMState *env, uint32_t ireg, uint32_t def,
-                          uint32_t rn, uint32_t maxindex)
+uint32_t HELPER(neon_tbl)(uint32_t ireg, uint32_t def, void *vn,
+                          uint32_t maxindex)
 {
-    uint32_t val;
-    uint32_t tmp;
-    int index;
-    int shift;
-    uint64_t *table;
-    table = (uint64_t *)&env->vfp.regs[rn];
+    uint32_t val, shift;
+    uint64_t *table = vn;
+
     val = 0;
     for (shift = 0; shift < 32; shift += 8) {
-        index = (ireg >> shift) & 0xff;
+        uint32_t index = (ireg >> shift) & 0xff;
         if (index < maxindex) {
-            tmp = (table[index >> 3] >> ((index & 7) << 3)) & 0xff;
+            uint32_t tmp = (table[index >> 3] >> ((index & 7) << 3)) & 0xff;
             val |= tmp << shift;
         } else {
             val |= def & (0xff << shift);
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 6f02c56..852d2a7 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -7544,9 +7544,9 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn)
                     tcg_gen_movi_i32(tmp, 0);
                 }
                 tmp2 = neon_load_reg(rm, 0);
-                tmp4 = tcg_const_i32(rn);
+                ptr1 = vfp_reg_ptr(true, rn);
                 tmp5 = tcg_const_i32(n);
-                gen_helper_neon_tbl(tmp2, cpu_env, tmp2, tmp, tmp4, tmp5);
+                gen_helper_neon_tbl(tmp2, tmp2, tmp, ptr1, tmp5);
                 tcg_temp_free_i32(tmp);
                 if (insn & (1 << 6)) {
                     tmp = neon_load_reg(rd, 1);
@@ -7555,9 +7555,9 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn)
                     tcg_gen_movi_i32(tmp, 0);
                 }
                 tmp3 = neon_load_reg(rm, 1);
-                gen_helper_neon_tbl(tmp3, cpu_env, tmp3, tmp, tmp4, tmp5);
+                gen_helper_neon_tbl(tmp3, tmp3, tmp, ptr1, tmp5);
                 tcg_temp_free_i32(tmp5);
-                tcg_temp_free_i32(tmp4);
+                tcg_temp_free_ptr(ptr1);
                 neon_store_reg(rd, 0, tmp2);
                 neon_store_reg(rd, 1, tmp3);
                 tcg_temp_free_i32(tmp);
-- 
2.7.4