[Qemu-devel] [PATCH v3 09/13] target/mips: Add emulation of MMI instruction PEXTLH

[Mateja Marjanovic]

From: Mateja Marjanovic <address@hidden>

Add emulation of MMI instruction PEXTLH. The emulation is implemented
using TCG front end operations directly to achieve better performance.

Signed-off-by: Mateja Marjanovic <address@hidden>
---
 target/mips/translate.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 69 insertions(+), 1 deletion(-)

diff --git a/target/mips/translate.c b/target/mips/translate.c
index e84262f..5c2fc07 100644
--- a/target/mips/translate.c
+++ b/target/mips/translate.c
@@ -24874,6 +24874,72 @@ static void gen_mmi_pextlb(DisasContext *ctx)
     }
 }
 
+/*
+ *  PEXTLH rd, rs, rt
+ *
+ *  Parallel Extend Lower from Halfword
+ *
+ *   1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
+ *  +-----------+---------+---------+---------+---------+-----------+
+ *  |    MMI    |    rs   |   rt    |   rd    | PEXTLH  |    MMI0   |
+ *  +-----------+---------+---------+---------+---------+-----------+
+ */
+
+static void gen_mmi_pextlh(DisasContext *ctx)
+{
+    uint32_t rs, rt, rd;
+    uint32_t opcode;
+
+    opcode = ctx->opcode;
+
+    rs = extract32(opcode, 21, 5);
+    rt = extract32(opcode, 16, 5);
+    rd = extract32(opcode, 11, 5);
+
+    if (rd == 0) {
+        /* nop */
+    } else {
+        TCGv_i64 t0 = tcg_temp_new();
+        TCGv_i64 t1 = tcg_temp_new();
+        uint64_t mask = ((1ULL << 16) - 1) << 48;
+
+        tcg_gen_movi_i64(t1, 0);
+        tcg_gen_andi_i64(t0, cpu_gpr[rs], mask);
+        tcg_gen_or_i64(t1, t0, t1);
+        tcg_gen_andi_i64(t0, cpu_gpr[rt], mask);
+        tcg_gen_shri_i64(t0, t0, 16);
+        tcg_gen_or_i64(t1, t0, t1);
+        mask >>= 16;
+        tcg_gen_andi_i64(t0, cpu_gpr[rs], mask);
+        tcg_gen_or_i64(t1, t0, t1);
+        tcg_gen_andi_i64(t0, cpu_gpr[rt], mask);
+        tcg_gen_shri_i64(t0, t0, 16);
+        tcg_gen_or_i64(t1, t0, t1);
+
+        tcg_gen_mov_i64(cpu_mmr[rd], t1);
+
+        mask >>= 16;
+        tcg_gen_movi_i64(t1, 0);
+        tcg_gen_andi_i64(t0, cpu_gpr[rs], mask);
+        tcg_gen_or_i64(t1, t0, t1);
+        tcg_gen_andi_i64(t0, cpu_gpr[rt], mask);
+        tcg_gen_shri_i64(t0, t0, 16);
+        tcg_gen_or_i64(t1, t0, t1);
+        mask >>= 16;
+        tcg_gen_andi_i64(t0, cpu_gpr[rs], mask);
+        tcg_gen_or_i64(t1, t0, t1);
+        tcg_gen_andi_i64(t0, cpu_gpr[rt], mask);
+        tcg_gen_shri_i64(t0, t0, 16);
+        tcg_gen_or_i64(t1, t0, t1);
+        mask >>= 16;
+
+        tcg_gen_mov_i64(cpu_gpr[rd], t1);
+
+        tcg_temp_free(t0);
+        tcg_temp_free(t1);
+    }
+}
+
 #endif
 
 
@@ -27825,7 +27891,6 @@ static void decode_mmi0(CPUMIPSState *env, DisasContext 
*ctx)
     case MMI_OPC_0_PPACW:     /* TODO: MMI_OPC_0_PPACW */
     case MMI_OPC_0_PADDSH:    /* TODO: MMI_OPC_0_PADDSH */
     case MMI_OPC_0_PSUBSH:    /* TODO: MMI_OPC_0_PSUBSH */
-    case MMI_OPC_0_PEXTLH:    /* TODO: MMI_OPC_0_PEXTLH */
     case MMI_OPC_0_PPACH:     /* TODO: MMI_OPC_0_PPACH */
     case MMI_OPC_0_PADDSB:    /* TODO: MMI_OPC_0_PADDSB */
     case MMI_OPC_0_PSUBSB:    /* TODO: MMI_OPC_0_PSUBSB */
@@ -27837,6 +27902,9 @@ static void decode_mmi0(CPUMIPSState *env, DisasContext 
*ctx)
    case MMI_OPC_0_PEXTLB:
         gen_mmi_pextlb(ctx);
         break;
+    case MMI_OPC_0_PEXTLH:
+        gen_mmi_pextlh(ctx);
+        break;
     default:
         MIPS_INVAL("TX79 MMI class MMI0");
         generate_exception_end(ctx, EXCP_RI);
-- 
2.7.4