ppc: spapr: cleanup cr get/set with helpers.

The bits in cr reg are grouped into eight 4-bit fields represented
by env->crf[8] and the related calculations should be abstracted to
keep the calling routines simpler to read. This is a step towards
cleaning up the related/calling code for better readability.

Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230503093619.2530487-2-harshpb@linux.ibm.com>
[danielhb: add 'const' modifier to fix linux-user build]
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

target/ppc/cpu.c

@@ -67,6 +67,23 @@ uint32_t ppc_get_vscr(CPUPPCState *env)
     return env->vscr | (sat << VSCR_SAT);
 }
 
+void ppc_set_cr(CPUPPCState *env, uint64_t cr)
+{
+    for (int i = 7; i >= 0; i--) {
+        env->crf[i] = cr & 0xf;
+        cr >>= 4;
+    }
+}
+
+uint64_t ppc_get_cr(const CPUPPCState *env)
+{
+    uint64_t cr = 0;
+    for (int i = 0; i < 8; i++) {
+        cr |= (env->crf[i] & 0xf) << (4 * (7 - i));
+    }
+    return cr;
+}
+
 /* GDBstub can read and write MSR... */
 void ppc_store_msr(CPUPPCState *env, target_ulong value)
 {

target/ppc/cpu.h

@@ -2773,6 +2773,8 @@ void dump_mmu(CPUPPCState *env);
 void ppc_maybe_bswap_register(CPUPPCState *env, uint8_t *mem_buf, int len);
 void ppc_store_vscr(CPUPPCState *env, uint32_t vscr);
 uint32_t ppc_get_vscr(CPUPPCState *env);
+void ppc_set_cr(CPUPPCState *env, uint64_t cr);
+uint64_t ppc_get_cr(const CPUPPCState *env);
 
 /*****************************************************************************/
 /* Power management enable checks                                            */

target/ppc/gdbstub.c

@@ -145,11 +145,7 @@ int ppc_cpu_gdb_read_register(CPUState *cs, GByteArray *buf, int n)
             break;
         case 66:
             {
-                uint32_t cr = 0;
-                int i;
-                for (i = 0; i < 8; i++) {
-                    cr |= env->crf[i] << (32 - ((i + 1) * 4));
-                }
+                uint32_t cr = ppc_get_cr(env);
                 gdb_get_reg32(buf, cr);
                 break;
             }
@@ -203,11 +199,7 @@ int ppc_cpu_gdb_read_register_apple(CPUState *cs, GByteArray *buf, int n)
             break;
         case 66 + 32:
             {
-                uint32_t cr = 0;
-                int i;
-                for (i = 0; i < 8; i++) {
-                    cr |= env->crf[i] << (32 - ((i + 1) * 4));
-                }
+                uint32_t cr = ppc_get_cr(env);
                 gdb_get_reg32(buf, cr);
                 break;
             }
@@ -257,10 +249,7 @@ int ppc_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
         case 66:
             {
                 uint32_t cr = ldl_p(mem_buf);
-                int i;
-                for (i = 0; i < 8; i++) {
-                    env->crf[i] = (cr >> (32 - ((i + 1) * 4))) & 0xF;
-                }
+                ppc_set_cr(env, cr);
                 break;
             }
         case 67:
@@ -307,10 +296,7 @@ int ppc_cpu_gdb_write_register_apple(CPUState *cs, uint8_t *mem_buf, int n)
         case 66 + 32:
             {
                 uint32_t cr = ldl_p(mem_buf);
-                int i;
-                for (i = 0; i < 8; i++) {
-                    env->crf[i] = (cr >> (32 - ((i + 1) * 4))) & 0xF;
-                }
+                ppc_set_cr(env, cr);
                 break;
             }
         case 67 + 32:

target/ppc/kvm.c

@@ -927,10 +927,7 @@ int kvm_arch_put_registers(CPUState *cs, int level)
         regs.gpr[i] = env->gpr[i];
     }
 
-    regs.cr = 0;
-    for (i = 0; i < 8; i++) {
-        regs.cr |= (env->crf[i] & 15) << (4 * (7 - i));
-    }
+    regs.cr = ppc_get_cr(env);
 
     ret = kvm_vcpu_ioctl(cs, KVM_SET_REGS, &regs);
     if (ret < 0) {
@@ -1205,7 +1202,6 @@ int kvm_arch_get_registers(CPUState *cs)
     PowerPCCPU *cpu = POWERPC_CPU(cs);
     CPUPPCState *env = &cpu->env;
     struct kvm_regs regs;
-    uint32_t cr;
     int i, ret;
 
     ret = kvm_vcpu_ioctl(cs, KVM_GET_REGS, &regs);
@@ -1213,12 +1209,7 @@ int kvm_arch_get_registers(CPUState *cs)
         return ret;
     }
 
-    cr = regs.cr;
-    for (i = 7; i >= 0; i--) {
-        env->crf[i] = cr & 15;
-        cr >>= 4;
-    }
-
+    ppc_set_cr(env, regs.cr);
     env->ctr = regs.ctr;
     env->lr = regs.lr;
     cpu_write_xer(env, regs.xer);

target/ppc/ppc-qmp-cmds.c

@@ -37,12 +37,8 @@ static target_long monitor_get_ccr(Monitor *mon, const struct MonitorDef *md,
 {
     CPUArchState *env = mon_get_cpu_env(mon);
     unsigned int u;
-    int i;
 
-    u = 0;
-    for (i = 0; i < 8; i++) {
-        u |= env->crf[i] << (32 - (4 * (i + 1)));
-    }
+    u = ppc_get_cr(env);
 
     return u;
 }