Initial support for saturated arithmetic

The tinygo compiler would sometimes use these instructions making it very useful to have them.

Author: MaartenS11

src/Interpreter/instructions.cpp

@@ -1294,6 +1294,54 @@ bool i_instr_extension(Module *m, uint8_t opcode) {
     return true;
 }
 
+/**
+ * 0xfc misc operations for saturated arithmetic and bulk memory/tables
+ */
+bool i_instr_sat_bulk(Module *m) {
+    uint32_t opcode = read_LEB_32(&m->pc_ptr);
+    switch (opcode) {
+        case 0x00: // i32.trunc_sat_s_f32
+            m->stack[m->sp].value.int32 = m->stack[m->sp].value.f32;
+            m->stack[m->sp].value_type = I32;
+            break;
+        case 0x01: // i32.trunc_sat_u_f32
+            m->stack[m->sp].value.uint32 = m->stack[m->sp].value.f32;
+            m->stack[m->sp].value_type = I32;
+            break;
+        case 0x02: // i32.trunc_sat_s_f64
+            m->stack[m->sp].value.int32 = m->stack[m->sp].value.f64;
+            m->stack[m->sp].value_type = I32;
+            break;
+        case 0x03: // i32.trunc_sat_u_f64
+            m->stack[m->sp].value.uint32 = m->stack[m->sp].value.f64;
+            m->stack[m->sp].value_type = I32;
+            break;
+        case 0x04: // i64.trunc_sat_s_f32
+            m->stack[m->sp].value.int64 = m->stack[m->sp].value.f32;
+            m->stack[m->sp].value_type = I64;
+            break;
+        case 0x05: // i64.trunc_sat_u_f32
+            m->stack[m->sp].value.uint64 = m->stack[m->sp].value.f32;
+            m->stack[m->sp].value_type = I64;
+            break;
+        case 0x06: // i64.trunc_sat_s_f64
+            m->stack[m->sp].value.int64 = m->stack[m->sp].value.f64;
+            m->stack[m->sp].value_type = I64;
+            break;
+        case 0x07: // i64.trunc_sat_u_f32
+            m->stack[m->sp].value.uint64 = m->stack[m->sp].value.f64;
+            m->stack[m->sp].value_type = I64;
+            break;
+        case 0x08 ... 0x11:
+            FATAL("Bulk memory/table operations currently not supported!\n");
+            break;
+        default:
+            return false;
+    }
+
+    return true;
+}
+
 /**
  * 0xe0 ... 0xe3 callback operations
  */

src/Interpreter/instructions.h

@@ -74,4 +74,6 @@ bool i_instr_conversion(Module *m, uint8_t opcode);
 
 bool i_instr_extension(Module *m, uint8_t opcode);
 
+bool i_instr_sat_bulk(Module *m);
+
 bool i_instr_callback(Module *m, uint8_t opcode);

src/Interpreter/interpreter.cpp

@@ -440,6 +440,9 @@ bool Interpreter::interpret(Module *m, bool waiting) {
             case 0xc0 ... 0xc4:
                 success &= i_instr_extension(m, opcode);
                 continue;
+                // saturated arithmetic + bulk operations
+            case 0xfc:
+                success &= i_instr_sat_bulk(m);
 
                 // callback operations
             case 0xe0 ... 0xe3: