[Qemu-devel] [PATCH v2 09/10] target-arm: optimize neon vld/vst ops

[juha . riihimaki]

From: Juha Riihimäki <address@hidden>

Reduce the amount of TCG ops generated from NEON vld/vst instructions
by simplifying the code generation.

Signed-off-by: Juha Riihimäki <address@hidden>
---
 target-arm/translate.c |   67 ++++++++++++++++++++++++-----------------------
 1 files changed, 34 insertions(+), 33 deletions(-)

diff --git a/target-arm/translate.c b/target-arm/translate.c
index f262758..55d6377 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -3708,6 +3708,7 @@ static int disas_neon_ls_insn(CPUState * env, 
DisasContext *s, uint32_t insn)
     TCGv tmp;
     TCGv tmp2;
     TCGv_i64 tmp64;
+    TCGv stride_var;
 
     if (!vfp_enabled(env))
       return 1;
@@ -3729,6 +3730,7 @@ static int disas_neon_ls_insn(CPUState * env, 
DisasContext *s, uint32_t insn)
             return 1;
         load_reg_var(s, addr, rn);
         stride = (1 << size) * interleave;
+        stride_var = tcg_const_i32(stride);
         for (reg = 0; reg < nregs; reg++) {
             if (interleave > 2 || (interleave == 2 && nregs == 2)) {
                 load_reg_var(s, addr, rn);
@@ -3747,7 +3749,7 @@ static int disas_neon_ls_insn(CPUState * env, 
DisasContext *s, uint32_t insn)
                     neon_load_reg64(tmp64, rd);
                     gen_st64(tmp64, addr, IS_USER(s));
                 }
-                tcg_gen_addi_i32(addr, addr, stride);
+                tcg_gen_add_i32(addr, addr, stride_var);
             } else {
                 for (pass = 0; pass < 2; pass++) {
                     if (size == 2) {
@@ -3758,58 +3760,57 @@ static int disas_neon_ls_insn(CPUState * env, 
DisasContext *s, uint32_t insn)
                             tmp = neon_load_reg(rd, pass);
                             gen_st32(tmp, addr, IS_USER(s));
                         }
-                        tcg_gen_addi_i32(addr, addr, stride);
+                        tcg_gen_add_i32(addr, addr, stride_var);
                     } else if (size == 1) {
                         if (load) {
                             tmp = gen_ld16u(addr, IS_USER(s));
-                            tcg_gen_addi_i32(addr, addr, stride);
+                            tcg_gen_add_i32(addr, addr, stride_var);
                             tmp2 = gen_ld16u(addr, IS_USER(s));
-                            tcg_gen_addi_i32(addr, addr, stride);
-                            gen_bfi(tmp, tmp, tmp2, 16, 0xffff);
+                            tcg_gen_add_i32(addr, addr, stride_var);
+                            tcg_gen_shli_i32(tmp2, tmp2, 16);
+                            tcg_gen_or_i32(tmp, tmp, tmp2);
                             dead_tmp(tmp2);
                             neon_store_reg(rd, pass, tmp);
                         } else {
                             tmp = neon_load_reg(rd, pass);
-                            tmp2 = new_tmp();
-                            tcg_gen_shri_i32(tmp2, tmp, 16);
-                            gen_st16(tmp, addr, IS_USER(s));
-                            tcg_gen_addi_i32(addr, addr, stride);
-                            gen_st16(tmp2, addr, IS_USER(s));
-                            tcg_gen_addi_i32(addr, addr, stride);
+                            tcg_gen_qemu_st16(tmp, addr, IS_USER(s));
+                            tcg_gen_add_i32(addr, addr, stride_var);
+                            tcg_gen_shri_i32(tmp, tmp, 16);
+                            tcg_gen_qemu_st16(tmp, addr, IS_USER(s));
+                            tcg_gen_add_i32(addr, addr, stride_var);
+                            dead_tmp(tmp);
                         }
                     } else /* size == 0 */ {
                         if (load) {
-                            TCGV_UNUSED(tmp2);
-                            for (n = 0; n < 4; n++) {
-                                tmp = gen_ld8u(addr, IS_USER(s));
-                                tcg_gen_addi_i32(addr, addr, stride);
-                                if (n == 0) {
-                                    tmp2 = tmp;
-                                } else {
-                                    gen_bfi(tmp2, tmp2, tmp, n * 8, 0xff);
-                                    dead_tmp(tmp);
-                                }
+                            tmp = gen_ld8u(addr, IS_USER(s));
+                            tcg_gen_add_i32(addr, addr, stride_var);
+                            for (n = 1; n < 4; n++) {
+                                tmp2 = gen_ld8u(addr, IS_USER(s));
+                                tcg_gen_add_i32(addr, addr, stride_var);
+                                tcg_gen_shli_i32(tmp2, tmp2, n * 8);
+                                tcg_gen_or_i32(tmp, tmp, tmp2);
+                                dead_tmp(tmp2);
                             }
-                            neon_store_reg(rd, pass, tmp2);
+                            neon_store_reg(rd, pass, tmp);
                         } else {
-                            tmp2 = neon_load_reg(rd, pass);
-                            for (n = 0; n < 4; n++) {
-                                tmp = new_tmp();
-                                if (n == 0) {
-                                    tcg_gen_mov_i32(tmp, tmp2);
-                                } else {
-                                    tcg_gen_shri_i32(tmp, tmp2, n * 8);
-                                }
-                                gen_st8(tmp, addr, IS_USER(s));
-                                tcg_gen_addi_i32(addr, addr, stride);
+                            tmp2 = tcg_const_i32(8);
+                            tmp = neon_load_reg(rd, pass);
+                            for (n = 0; n < 3; n++) {
+                                tcg_gen_qemu_st8(tmp, addr, IS_USER(s));
+                                tcg_gen_add_i32(addr, addr, stride_var);
+                                tcg_gen_shr_i32(tmp, tmp, tmp2);
                             }
-                            dead_tmp(tmp2);
+                            tcg_gen_qemu_st8(tmp, addr, IS_USER(s));
+                            tcg_gen_add_i32(addr, addr, stride_var);
+                            dead_tmp(tmp);
+                            tcg_temp_free_i32(tmp2);
                         }
                     }
                 }
             }
             rd += spacing;
         }
+        tcg_temp_free_i32(stride_var);
         stride = nregs * 8;
     } else {
         size = (insn >> 10) & 3;
-- 
1.6.5