[Qemu-devel] [PATCH v2 3/9] target-s390: Implement SAM31 and SAM64

[Richard Henderson <rth@twiddle.net>]

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 target-s390x/insn-data.def |  8 ++++----
 target-s390x/translate.c   | 26 ++++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/target-s390x/insn-data.def b/target-s390x/insn-data.def
index 4b462d4..c528eb4 100644
--- a/target-s390x/insn-data.def
+++ b/target-s390x/insn-data.def
@@ -566,6 +566,10 @@
 
 /* SET ACCESS */
     C(0xb24e, SAR,     RRE,   Z,   0, r2_o, 0, 0, sar, 0)
+/* SET ADDRESSING MODE */
+    /* We only do 32 and 64-bit.  Let SAM24 signal illegal instruction.  */
+    C(0x010d, SAM31,   E,     Z,   0, 0, 0, 0, sam31, 0)
+    C(0x010e, SAM64,   E,     Z,   0, 0, 0, 0, sam64, 0)
 /* SET FPC */
     C(0xb384, SFPC,    RRE,   Z,   0, r1_o, 0, 0, sfpc, 0)
 /* SET FPC AND SIGNAL */
@@ -745,10 +749,6 @@
     C(0xb22a, RRBE,    RRE,   Z,   0, r2_o, 0, 0, rrbe, 0)
 /* SERVICE CALL LOGICAL PROCESSOR (PV hypercall) */
     C(0xb220, SERVC,   RRE,   Z,   r1_o, r2_o, 0, 0, servc, 0)
-/* SET ADDRESSING MODE */
-    /* We only do 64-bit, so accept this as a no-op.
-       Let SAM24 and SAM31 signal illegal instruction.  */
-    C(0x010e, SAM64,   E,     Z,   0, 0, 0, 0, 0, 0)
 /* SET ADDRESS SPACE CONTROL FAST */
     C(0xb279, SACF,    S,     Z,   0, a2, 0, 0, sacf, 0)
 /* SET CLOCK */
diff --git a/target-s390x/translate.c b/target-s390x/translate.c
index 7356625..f8732bb 100644
--- a/target-s390x/translate.c
+++ b/target-s390x/translate.c
@@ -2912,6 +2912,32 @@ static ExitStatus op_sacf(DisasContext *s, DisasOps *o)
 }
 #endif
 
+static ExitStatus op_sam31(DisasContext *s, DisasOps *o)
+{
+    /* Bizzare but true, we check the address of the current insn for the
+       specification exception, not the next to be executed.  Thus the PoO
+       documents that Bad Things Happen at 0x7ffffffe.  */
+    if (s->pc & ~0x7ffffff) {
+        gen_program_exception(s, PGM_SPECIFICATION);
+        return EXIT_NORETURN;
+    }
+    s->next_pc &= 0x7fffffff;
+
+    tcg_gen_andi_i64(psw_mask, psw_mask, ~PSW_MASK_64);
+    tcg_gen_ori_i64(psw_mask, psw_mask, PSW_MASK_32);
+
+    /* Always exit the TB, since we (may have) changed execution mode.  */
+    return EXIT_PC_STALE;
+}
+
+static ExitStatus op_sam64(DisasContext *s, DisasOps *o)
+{
+    tcg_gen_ori_i64(psw_mask, psw_mask, PSW_MASK_32 | PSW_MASK_64);
+
+    /* Always exit the TB, since we (may have) changed execution mode.  */
+    return EXIT_PC_STALE;
+}
+
 static ExitStatus op_sar(DisasContext *s, DisasOps *o)
 {
     int r1 = get_field(s->fields, r1);
-- 
1.8.1.4