sim: cgen: add MUL2OFSI and MUL1OFSI functions (needed for OR1K l.mul[u])

sim/common/ChangeLog:

2017-12-12  Peter Gavin  <pgavin@gmail.com>
	    Stafford Horne  <shorne@gmail.com>

	* cgen-ops.h (MUL2OFSI): New function, 2's complement overflow
	flag.
	(MUL1OFSI): New function, 1's complement overflow flag.

sim/common/ChangeLog

@@ -1,3 +1,10 @@
+2017-12-12  Peter Gavin  <pgavin@gmail.com>
+	    Stafford Horne  <shorne@gmail.com>
+
+	* cgen-ops.h (MUL2OFSI): New function, 2's complement overflow
+	flag.
+	(MUL1OFSI): New function, 1's complement overflow flag.
+
 2017-12-12  Peter Gavin  <pgavin@gmail.com>
 	    Stafford Horne <shorne@gmail.com>
 

sim/common/cgen-ops.h

@@ -631,6 +631,22 @@ SUBOFQI (QI a, QI b, BI c)
   return res;
 }
 
+SEMOPS_INLINE BI
+MUL2OFSI (SI a, SI b)
+{
+  DI tmp = MULDI (EXTSIDI (a), EXTSIDI (b));
+  BI res = tmp < -0x80000000LL || tmp > 0x7fffffffLL;
+  return res;
+}
+
+SEMOPS_INLINE BI
+MUL1OFSI (USI a, USI b)
+{
+  UDI tmp = MULDI (ZEXTSIDI (a), ZEXTSIDI (b));
+  BI res = (tmp > 0xFFFFFFFFULL);
+  return res;
+}
+
 #else
 
 SI ADDCSI (SI, SI, BI);
@@ -651,6 +667,8 @@ UBI ADDOFQI (QI, QI, BI);
 QI SUBCQI (QI, QI, BI);
 UBI SUBCFQI (QI, QI, BI);
 UBI SUBOFQI (QI, QI, BI);
+BI MUL1OFSI (SI a, SI b);
+BI MUL2OFSI (SI a, SI b);
 
 #endif