Added rough emulation support for div/rem/mul.

4 files changed, 77 insertions, 1 deletions

diff --git a/pk/handlers.c b/pk/handlers.c
index 817f14d..8b959e8 100644
--- a/pk/handlers.c
+++ b/pk/handlers.c
@@ -4,7 +4,7 @@
 
 int have_fp = 1; // initialized to 1 because it can't be in the .bss section!
 int have_vector = 1;
-
+  
 static void handle_vector_disabled(trapframe_t* tf)
 {
   if (have_vector)
@@ -41,6 +41,12 @@ static void handle_illegal_instruction(trapframe_t* tf)
   }
 #endif
 
+  if(emulate_int(tf) == 0)
+  {
+    advance_pc(tf);
+    return;
+  }
+
   dump_tf(tf);
   panic("An illegal instruction was executed!");
 }
diff --git a/pk/int.c b/pk/int.c
new file mode 100644
index 0000000..1424e73
--- /dev/null
+++ b/pk/int.c
@@ -0,0 +1,66 @@
+#include "pk.h"
+#include "pcr.h"
+
+
+#include "softint.h"
+#include "riscv-opc.h"
+#include <stdint.h>
+
+#define noisy 0
+
+
+int emulate_int(trapframe_t* tf)
+{
+  if(noisy)
+    printk("Int emulation at pc %lx, insn %x\n",tf->epc,(uint32_t)tf->insn);
+
+  #define RS1 ((tf->insn >> 22) & 0x1F)
+  #define RS2 ((tf->insn >> 17) & 0x1F)
+  #define RD  ((tf->insn >> 27) & 0x1F)
+
+//  #define XRS1 (tf->gpr[RS1])
+//  #define XRS2 (tf->gpr[RS2])
+  #define XRD  (tf->gpr[RD])
+
+  unsigned long xrs1 = tf->gpr[RS1];
+  unsigned long xrs2 = tf->gpr[RS2];
+
+  #define IS_INSN(x) ((tf->insn & MASK_ ## x) == MATCH_ ## x)
+   
+  if(IS_INSN(DIV))
+  {
+    if(noisy)
+      printk("emulating div\n");
+    XRD = softint_divu(xrs1, xrs2);
+  }
+  else if(IS_INSN(DIVU))
+  {
+    if(noisy)
+      printk("emulating divu\n");
+    XRD = softint_divu( xrs1, xrs2);
+  }
+  else if(IS_INSN(MUL))
+  {
+    if(noisy)
+      printk("emulating mul\n");
+    XRD = softint_mul(xrs1, xrs2);
+  }
+  else if(IS_INSN(REM))
+  {
+    if(noisy)
+      printk("emulating rem\n");
+    XRD = softint_remu(xrs1, xrs2);
+  }
+  else if(IS_INSN(REMU))
+  {
+    if(noisy)
+      printk("emulating remu\n");
+    XRD = softint_remu(xrs1, xrs2);
+  }
+  else
+    return -1;
+
+  return 0;
+}
+
+
diff --git a/pk/pk.h b/pk/pk.h
index 4c343a5..84d1b9a 100644
--- a/pk/pk.h
+++ b/pk/pk.h
@@ -32,6 +32,8 @@ extern uint32_t mem_mb;
 int emulate_fp(trapframe_t*);
 void init_fp(trapframe_t* tf);
 
+int emulate_int(trapframe_t*);
+
 void printk(const char* s, ...);
 void init_tf(trapframe_t*, long pc, long sp, int user64);
 void pop_tf(trapframe_t*);
diff --git a/pk/pk.mk.in b/pk/pk.mk.in
index 19e630c..2a3c863 100644
--- a/pk/pk.mk.in
+++ b/pk/pk.mk.in
@@ -1,6 +1,7 @@
 pk_subproject_deps = \
 	softfloat_riscv \
 	softfloat \
+	softint \
 
 pk_hdrs = \
 	pk.h \
@@ -19,6 +20,7 @@ pk_c_srcs = \
 	handlers.c \
 	frontend.c \
 	fp.c \
+	int.c \
 	memset.c \
 	strlen.c \
 	elf.c \