From 8869ad02bfd9737f6a8fceab5ca286eaa899b790 Mon Sep 17 00:00:00 2001
From: Yongbok Kim <yongbok.kim@mips.com>
Date: Thu, 2 Aug 2018 16:16:09 +0200
Subject: [PATCH] target/mips: Add emulation of nanoMIPS 16-bit misc
 instructions

Add emulation of misc nanoMIPS 16-bit instructions.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Yongbok Kim <yongbok.kim@mips.com>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Stefan Markovic <smarkovic@wavecomp.com>
---
 target/mips/translate.c | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/target/mips/translate.c b/target/mips/translate.c
index e3fac1ab0b..c774dc9e42 100644
--- a/target/mips/translate.c
+++ b/target/mips/translate.c
@@ -16763,6 +16763,40 @@ static int decode_nanomips_opc(CPUMIPSState *env, DisasContext *ctx)
     op = extract32(ctx->opcode, 10, 6);
     switch (op) {
     case NM_P16_MV:
+        rt = NANOMIPS_EXTRACT_RD5(ctx->opcode);
+        if (rt != 0) {
+            /* MOVE */
+            rs = NANOMIPS_EXTRACT_RS5(ctx->opcode);
+            gen_arith(ctx, OPC_ADDU, rt, rs, 0);
+        } else {
+            /* P16.RI */
+            switch (extract32(ctx->opcode, 3, 2)) {
+            case NM_P16_SYSCALL:
+                if (extract32(ctx->opcode, 2, 1) == 0) {
+                    generate_exception_end(ctx, EXCP_SYSCALL);
+                } else {
+                    generate_exception_end(ctx, EXCP_RI);
+                }
+                break;
+            case NM_BREAK16:
+                generate_exception_end(ctx, EXCP_BREAK);
+                break;
+            case NM_SDBBP16:
+                if (is_uhi(extract32(ctx->opcode, 0, 3))) {
+                    gen_helper_do_semihosting(cpu_env);
+                } else {
+                    if (ctx->hflags & MIPS_HFLAG_SBRI) {
+                        generate_exception_end(ctx, EXCP_RI);
+                    } else {
+                        generate_exception_end(ctx, EXCP_DBp);
+                    }
+                }
+                break;
+            default:
+                generate_exception_end(ctx, EXCP_RI);
+                break;
+            }
+        }
         break;
     case NM_P16_SHIFT:
         {
@@ -16842,6 +16876,13 @@ static int decode_nanomips_opc(CPUMIPSState *env, DisasContext *ctx)
         }
         break;
     case NM_LI16:
+        {
+            int imm = extract32(ctx->opcode, 0, 7);
+            imm = (imm == 0x7f ? -1 : imm);
+            if (rt != 0) {
+                tcg_gen_movi_tl(cpu_gpr[rt], imm);
+            }
+        }
         break;
     case NM_ANDI16:
         break;