[PATCH] linux-user/sparc64: Translate flushw opcode

[LemonBoy <thatlemon@gmail.com>]

From 11d0cfe58d12e0f191b435ade88622cfceb2098a Mon Sep 17 00:00:00 2001
From: LemonBoy <thatlemon@gmail.com>
Date: Fri, 10 Apr 2020 22:55:26 +0200
Subject: [PATCH] linux-user/sparc64: Translate flushw opcode

The ifdef logic should unconditionally compile in the `xop == 0x2b` case
when targeting sparc64.

Fix the handling of window spill traps by keeping cansave into account
when calculating the new CWP.

Signed-off-by: Giuseppe Musacchio <thatlemon@gmail.com>
---
 bsd-user/main.c             | 4 +++-
 linux-user/sparc/cpu_loop.c | 4 +++-
 target/sparc/translate.c    | 2 ++
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/bsd-user/main.c b/bsd-user/main.c
index 770c2b267a..d6b1c997e3 100644
--- a/bsd-user/main.c
+++ b/bsd-user/main.c
@@ -413,7 +413,9 @@ static void save_window(CPUSPARCState *env)
     save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
     env->wim = new_wim;
 #else
-    save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
+    /* cansave is zero if the spill trap handler is triggered by `save` and */
+    /* nonzero if triggered by a `flushw` */
+    save_window_offset(env, cpu_cwp_dec(env, env->cwp - env->cansave - 2));
     env->cansave++;
     env->canrestore--;
 #endif
diff --git a/linux-user/sparc/cpu_loop.c b/linux-user/sparc/cpu_loop.c
index 7645cc04ca..20a7401126 100644
--- a/linux-user/sparc/cpu_loop.c
+++ b/linux-user/sparc/cpu_loop.c
@@ -69,7 +69,9 @@ static void save_window(CPUSPARCState *env)
     save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
     env->wim = new_wim;
 #else
-    save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
+    /* cansave is zero if the spill trap handler is triggered by `save` and */
+    /* nonzero if triggered by a `flushw` */
+    save_window_offset(env, cpu_cwp_dec(env, env->cwp - env->cansave - 2));
     env->cansave++;
     env->canrestore--;
 #endif
diff --git a/target/sparc/translate.c b/target/sparc/translate.c
index 9416a551cf..1a4efd4ed6 100644
--- a/target/sparc/translate.c
+++ b/target/sparc/translate.c
@@ -3663,6 +3663,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
 #endif
                 gen_store_gpr(dc, rd, cpu_tmp0);
                 break;
+#endif
+#if defined(TARGET_SPARC64) || !defined(CONFIG_USER_ONLY)
             } else if (xop == 0x2b) { /* rdtbr / V9 flushw */
 #ifdef TARGET_SPARC64
                 gen_helper_flushw(cpu_env);
-- 
2.20.1