Avoid stack overflow with -msoft-float

pk/fp_asm.S

@@ -1,5 +1,7 @@
 // See LICENSE for license details.
 
+#ifdef __riscv_hard_float
+
 #define get_f32(which) fmv.x.s a0, which; jr t0
 #define put_f32(which) fmv.s.x which, a0; jr t0
 #ifdef __riscv64
@@ -153,3 +155,5 @@
     put_f64(f29)
     put_f64(f30)
     put_f64(f31)
+
+#endif

pk/init.c

@@ -84,7 +84,7 @@ struct mainvars* parse_args(struct mainvars* args)
   return (struct mainvars*)&args->argv[a0-1];
 }
 
-void boot_loader(struct mainvars* args)
+void load_program(struct mainvars* args)
 {
   // load program named by argv[0]
   long phdrs[128];
@@ -93,6 +93,4 @@ void boot_loader(struct mainvars* args)
   if (!args->argc)
     panic("tell me what ELF to load!");
   load_elf((char*)(uintptr_t)args->argv[0], &current);
-
-  run_loaded_program(args);
 }

pk/minit.c

@@ -67,7 +67,8 @@ static void init_first_hart()
 
   memory_init();
   vm_init();
-  boot_loader(args);
+  load_program(args);
+  run_loaded_program(args);
 }
 
 static void init_other_hart()

pk/pk.h

@@ -60,7 +60,7 @@ void handle_misaligned_load(trapframe_t*);
 void handle_misaligned_store(trapframe_t*);
 void handle_fault_load(trapframe_t*);
 void handle_fault_store(trapframe_t*);
-void boot_loader(struct mainvars*);
+void load_program(struct mainvars*);
 void run_loaded_program(struct mainvars*);
 void boot_other_hart();