target-s390: Reorg exception handling

Make the user path more like the system path.  Prepare for more kinds
of runtime exceptions.  Rename ILC to ILEN to make it clear that we
want to pass around a full instruction length, rather than a "code"
that happens to be stored one bit left in a larger field.

Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 22 insertions, 27 deletions

diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
index 529716de47..83e618ab0e 100644
--- a/target-s390x/cpu.h
+++ b/target-s390x/cpu.h
@@ -79,10 +79,10 @@ typedef struct CPUS390XState {
     uint64_t psa;
 
     uint32_t int_pgm_code;
-    uint32_t int_pgm_ilc;
+    uint32_t int_pgm_ilen;
 
     uint32_t int_svc_code;
-    uint32_t int_svc_ilc;
+    uint32_t int_svc_ilen;
 
     uint64_t cregs[16]; /* control registers */
 
@@ -253,25 +253,31 @@ static inline void cpu_get_tb_cpu_state(CPUS390XState* env, target_ulong *pc,
              ((env->psw.mask & PSW_MASK_32) ? FLAG_MASK_32 : 0);
 }
 
-static inline int get_ilc(uint8_t opc)
+/* While the PoO talks about ILC (a number between 1-3) what is actually
+   stored in LowCore is shifted left one bit (an even between 2-6).  As
+   this is the actual length of the insn and therefore more useful, that
+   is what we want to pass around and manipulate.  To make sure that we
+   have applied this distinction universally, rename the "ILC" to "ILEN".  */
+static inline int get_ilen(uint8_t opc)
 {
     switch (opc >> 6) {
     case 0:
-        return 1;
+        return 2;
     case 1:
     case 2:
-        return 2;
-    case 3:
-        return 3;
+        return 4;
+    default:
+        return 6;
     }
-
-    return 0;
 }
 
-#define ILC_LATER       0x20
-#define ILC_LATER_INC   0x21
-#define ILC_LATER_INC_2 0x22
-
+#ifndef CONFIG_USER_ONLY
+/* In several cases of runtime exceptions, we havn't recorded the true
+   instruction length.  Use these codes when raising exceptions in order
+   to re-compute the length by examining the insn in memory.  */
+#define ILEN_LATER       0x20
+#define ILEN_LATER_INC   0x21
+#endif
 
 S390CPU *cpu_s390x_init(const char *cpu_model);
 void s390x_translate_init(void);
@@ -352,21 +358,10 @@ static inline void cpu_set_tls(CPUS390XState *env, target_ulong newtls)
 
 #include "exec/exec-all.h"
 
-#ifdef CONFIG_USER_ONLY
-
-#define EXCP_OPEX 1 /* operation exception (sigill) */
-#define EXCP_SVC 2 /* supervisor call (syscall) */
-#define EXCP_ADDR 5 /* addressing exception */
-#define EXCP_SPEC 6 /* specification exception */
-
-#else
-
 #define EXCP_EXT 1 /* external interrupt */
 #define EXCP_SVC 2 /* supervisor call (syscall) */
 #define EXCP_PGM 3 /* program interruption */
 
-#endif /* CONFIG_USER_ONLY */
-
 #define INTERRUPT_EXT        (1 << 0)
 #define INTERRUPT_TOD        (1 << 1)
 #define INTERRUPT_CPUTIMER   (1 << 2)
@@ -532,9 +527,9 @@ typedef struct LowCore
     uint32_t        ext_params;               /* 0x080 */
     uint16_t        cpu_addr;                 /* 0x084 */
     uint16_t        ext_int_code;             /* 0x086 */
-    uint16_t        svc_ilc;                  /* 0x088 */
+    uint16_t        svc_ilen;                 /* 0x088 */
     uint16_t        svc_code;                 /* 0x08a */
-    uint16_t        pgm_ilc;                  /* 0x08c */
+    uint16_t        pgm_ilen;                 /* 0x08c */
     uint16_t        pgm_code;                 /* 0x08e */
     uint32_t        data_exc_code;            /* 0x090 */
     uint16_t        mon_class_num;            /* 0x094 */
@@ -924,6 +919,6 @@ uint32_t set_cc_nz_f32(float32 v);
 uint32_t set_cc_nz_f64(float64 v);
 
 /* misc_helper.c */
-void program_interrupt(CPUS390XState *env, uint32_t code, int ilc);
+void program_interrupt(CPUS390XState *env, uint32_t code, int ilen);
 
 #endif