提交: 056c8c9d381867aa3d96bcf05e9a165e42771547 - libNibBit (git)

This is for exploring and demonstrating ways to extend the available integer math in C. Ｃコンパイラが提供する整数を拡張するための探険用のソースコードです。

Commit MetaInfo

• 修訂: 056c8c9d381867aa3d96bcf05e9a165e42771547 (tree)
• 時間: 2013-07-29 11:34:41
• 作者: Joel Matthew Rees <reiisi@user...>
• Commiter: Joel Matthew Rees

Log Message

Where I ran out of time last week. Demonstrats add/sub/mul/bitdiv.
C's lack of an overflow target for math (especially division) makes it hard to expand.
But division is hard anyway, and the carry/overflow for the rest really is not that bad.

Change Summary

• modified: Makefile
• modified: nibAdd.c
• modified: nibAddTest.c
• modified: nibBit.c
• modified: nibBit.h
• modified: nibDiv.c
• modified: nibDivTest.c
• modified: nibMul.c
• modified: nibSub.c
• modified: nibSubTest.c

差異

--- a/Makefile
+++ b/Makefile
@@ -17,7 +17,7 @@ nibObjects = nibBit.o
 nibLibObjects = nibMul.o nibDiv.o nibAdd.o nibSub.o 
 
 #nibExecutables = nibAddTest nibSubTest nibMulTest nibDivTest
-nibExecutables = nibAddTest nibSubTest nibMulTest 
+nibExecutables = nibAddTest nibSubTest nibMulTest nibDivTest
 
 #nibSources = nibBit.c
 
@@ -44,9 +44,9 @@ nibMul.o: nibBit.h
 
 nibMulTest: nibMulTest.o nibMul.o $(nibObjects)
 
-#nibDiv.o: nibDiv.c nibMul.c nibSub.c nibBit.h
+nibDiv.o: nibMul.o nibSub.o nibBit.h
 
-#nibDivTest: nibDivTest.o nibDiv.o nibSub.o $(nibObjects)
+nibDivTest: nibDivTest.o nibDiv.o $(nibObjects)
 
 
 # Note that the goal object is the independent of the LD/ST accumulator syntax.

--- a/nibAdd.c
+++ b/nibAdd.c
@@ -14,7 +14,7 @@
 
 /* Push order: left right 
 // return order: lsbyte msbyte
-// (most significant on bottom)
+// (most significant on top-of-stack -- low address)
 */
 void nibDAdd( void )
 {

--- a/nibAddTest.c
+++ b/nibAddTest.c
@@ -57,7 +57,7 @@ int main( int argc, char * argv[] )
             {  rangeMiss += 1;
 /*
                printf( "out-of-range(%ld): ", rangeMiss );
-               printf( "%ud + %ud = %ud synth: %ud\n",
+               printf( "%u + %u = %u synth: %u\n",
                        i, j, sum, synthetic );
                printf( "0x%05x + 0x%05x = 0x%05x synth: 0x%05x\n",
                        i, j, sum, synthetic );
@@ -66,7 +66,7 @@ int main( int argc, char * argv[] )
             else
             {  bad += 1;
                printf( "*** bad(%ld): ", bad );
-               printf( "%ud + %ud = %ud synth: %ud\n",
+               printf( "%u + %u = %u synth: %u\n",
                        i, j, sum, synthetic );
                printf( "0x%05x + 0x%05x = 0x%05x synth: 0x%05x\n",
                        i, j, sum, synthetic );

--- a/nibBit.c
+++ b/nibBit.c
@@ -16,6 +16,10 @@
 uchar_t myStack[ STACKDEPTH ];
 uchar_t * mySP = myStack + STACKDEPTH;
 
+/* This doesn't placate the warnings about myStack not being 
+// -- explicitly!! --
+// initialized.
+*/
 void initMyStack( void )
 {  mySP = myStack + STACKDEPTH;
 }

--- a/nibBit.h
+++ b/nibBit.h
@@ -56,6 +56,8 @@ extern void nibUMul( void );
 
 
 extern void nibUDiv( void );
+/* Sould be commented out except to show the high word in testing. */
+#define TESTUDIVHIGHWORD
 
 extern void nibBUDiv( void );
 

--- a/nibDiv.c
+++ b/nibDiv.c
@@ -206,9 +206,9 @@ printf( "nibble qHi: %d, qLo: %d, rem: %d\n",
 printf( "nibble qHi: %d, qLo: %d, rem: %d\n", 
         mySP[ 0 ], mySP[ 1 ], mySP[ 2 ] );
 */
-#else / * !defined TESTUDIVHIGHWORD * /
+#else /* !defined TESTUDIVHIGHWORD */
       ++mySP;
-#endif / * defined TESTUDIVHIGHWORD * /
+#endif /* defined TESTUDIVHIGHWORD */
 
       return;
    }

--- a/nibDivTest.c
+++ b/nibDivTest.c
@@ -63,9 +63,9 @@ return -1;
 
    initMyStack();
 
-   for ( i = dividendstart; i < dividendlimit; ++i )
+   for ( i = dividendstart; i <= dividendlimit; ++i )
    {  /* no divide by zero */
-      for ( j = divisorstart; j < divisorlimit; ++j )
+      for ( j = divisorstart; j <= divisorlimit; ++j )
       {  unsigned q = i / j;
          unsigned r = i % j;
          unsigned sq, sr, bq, br;

--- a/nibMul.c
+++ b/nibMul.c
@@ -14,7 +14,7 @@
 
 /* Push order: left right 
 // return order: lsbyte msbyte
-// (most significant on bottom)
+// (most significant on top-of-stack -- low address)
 */
 void nibUMul( void )
 {

--- a/nibSub.c
+++ b/nibSub.c
@@ -14,7 +14,7 @@
 
 /* Push order: left right 
 // return order: lsbyte msbyte
-// (most significant on bottom)
+// (most significant on top-of-stack -- low address)
 */
 void nibDSub( void )
 {

--- a/nibSubTest.c
+++ b/nibSubTest.c
@@ -1,4 +1,4 @@
-/* Addition tester for an eight-bit framework 
+/* Subtraction tester for an eight-bit framework 
 // for testing various arithmetic techniques.
 // Written by Joel Matthew Rees
 // Copyright 2013, Joel Matthew Rees