diff mbox

patch to fix constant math - first small patch

Message ID 506F5B50.2040800@naturalbridge.com
State New
Headers show

Commit Message

Kenneth Zadeck Oct. 5, 2012, 10:12 p.m. UTC 
this patch adds two groups of things to hwint.h that are needed for 
wide-int.[ch].

A new data type, the HOST_HALF_WIDE_INT (and all of it related 
macros).   This type is defined to be exactly 1/2 the width of a 
HOST_WIDE_INT.  This is used by the multiplication and division routines 
in wide-int.c.   This is the type for the "digits" that are multiplied 
together or divided since you want to do the largest multiplication that 
you can do that yields a HOST_WIDE_INT as the result.

The zext_hwi and sext_hwi are simple convenience functions on HWIs.   
These were moved from the wide-int.h in the original patch at the 
request of richi.

ok for commit?

Kenny
2012-10-5  Kenneth Zadeck <zadeck@naturalbridge.com>

	* hwint.h (HOST_BITS_PER_HALF_WIDE_INT, HOST_HALF_WIDE_INT,
	HOST_HALF_WIDE_INT_PRINT, HOST_HALF_WIDE_INT_PRINT_C,
	HOST_HALF_WIDE_INT_PRINT_DEC, HOST_HALF_WIDE_INT_PRINT_DEC_C,
	HOST_HALF_WIDE_INT_PRINT_UNSIGNED, HOST_HALF_WIDE_INT_PRINT_HEX,
	HOST_HALF_WIDE_INT_PRINT_HEX_PURE): New symbols.
	(sext_hwi, zext_hwi): New functions.

Comments

Joseph Myers Oct. 6, 2012, 12:14 a.m. UTC | #1 
On Fri, 5 Oct 2012, Kenneth Zadeck wrote:

> +# define HOST_HALF_WIDE_INT_PRINT "h"

This may cause problems on hosts not supporting %hd (MinGW?), and there's 
no real need for using "h" here given the promotion of short to int; you 
can just use "" (rather than e.g. needing special handling in xm-mingw32.h 
like is done for HOST_LONG_LONG_FORMAT).
Kenneth Zadeck Oct. 8, 2012, 7:25 p.m. UTC | #2 
is this ok to commit with this change?

kenny
On 10/05/2012 08:14 PM, Joseph S. Myers wrote:
> On Fri, 5 Oct 2012, Kenneth Zadeck wrote:
>
>> +# define HOST_HALF_WIDE_INT_PRINT "h"
> This may cause problems on hosts not supporting %hd (MinGW?), and there's
> no real need for using "h" here given the promotion of short to int; you
> can just use "" (rather than e.g. needing special handling in xm-mingw32.h
> like is done for HOST_LONG_LONG_FORMAT).
>
diff mbox

Patch

diff --git a/gcc/hwint.h b/gcc/hwint.h
index ca47148..07c4748 100644
--- a/gcc/hwint.h
+++ b/gcc/hwint.h
@@ -77,6 +77,40 @@  extern char sizeof_long_long_must_be_8[sizeof(long long) == 8 ? 1 : -1];
 # endif
 #endif
 
+/* Print support for half a host wide int.  */
+#define HOST_BITS_PER_HALF_WIDE_INT (HOST_BITS_PER_WIDE_INT / 2)
+#if HOST_BITS_PER_HALF_WIDE_INT == HOST_BITS_PER_LONG
+# define HOST_HALF_WIDE_INT long
+# define HOST_HALF_WIDE_INT_PRINT HOST_LONG_FORMAT
+# define HOST_HALF_WIDE_INT_PRINT_C "L"
+# define HOST_HALF_WIDE_INT_PRINT_DEC "%" HOST_HALF_WIDE_INT_PRINT "d"
+# define HOST_HALF_WIDE_INT_PRINT_DEC_C HOST_HALF_WIDE_INT_PRINT_DEC HOST_HALF_WIDE_INT_PRINT_C
+# define HOST_HALF_WIDE_INT_PRINT_UNSIGNED "%" HOST_HALF_WIDE_INT_PRINT "u"
+# define HOST_HALF_WIDE_INT_PRINT_HEX "%#" HOST_HALF_WIDE_INT_PRINT "x"
+# define HOST_HALF_WIDE_INT_PRINT_HEX_PURE "%" HOST_HALF_WIDE_INT_PRINT "x"
+#elif HOST_BITS_PER_HALF_WIDE_INT == HOST_BITS_PER_INT
+# define HOST_HALF_WIDE_INT int
+# define HOST_HALF_WIDE_INT_PRINT ""
+# define HOST_HALF_WIDE_INT_PRINT_C ""
+# define HOST_HALF_WIDE_INT_PRINT_DEC "%" HOST_HALF_WIDE_INT_PRINT "d"
+# define HOST_HALF_WIDE_INT_PRINT_DEC_C HOST_HALF_WIDE_INT_PRINT_DEC HOST_HALF_WIDE_INT_PRINT_C
+# define HOST_HALF_WIDE_INT_PRINT_UNSIGNED "%" HOST_HALF_WIDE_INT_PRINT "u"
+# define HOST_HALF_WIDE_INT_PRINT_HEX "%#" HOST_HALF_WIDE_INT_PRINT "x"
+# define HOST_HALF_WIDE_INT_PRINT_HEX_PURE "%" HOST_HALF_WIDE_INT_PRINT "x"
+#elif HOST_BITS_PER_HALF_WIDE_INT == HOST_BITS_PER_SHORT
+# define HOST_HALF_WIDE_INT short
+# define HOST_HALF_WIDE_INT_PRINT "h"
+# define HOST_HALF_WIDE_INT_PRINT_C ""
+# define HOST_HALF_WIDE_INT_PRINT_DEC "%" HOST_HALF_WIDE_INT_PRINT "d"
+# define HOST_HALF_WIDE_INT_PRINT_DEC_C HOST_HALF_WIDE_INT_PRINT_DEC HOST_HALF_WIDE_INT_PRINT_C
+# define HOST_HALF_WIDE_INT_PRINT_UNSIGNED "%" HOST_HALF_WIDE_INT_PRINT "u"
+# define HOST_HALF_WIDE_INT_PRINT_HEX "%#" HOST_HALF_WIDE_INT_PRINT "x"
+# define HOST_HALF_WIDE_INT_PRINT_HEX_PURE "%" HOST_HALF_WIDE_INT_PRINT "x"
+#else
+#error Please add support for HOST_HALF_WIDE_INT
+#endif
+
+
 #define HOST_WIDE_INT_1 HOST_WIDE_INT_C(1)
 
 /* This is a magic identifier which allows GCC to figure out the type
@@ -94,9 +128,13 @@  typedef HOST_WIDE_INT __gcc_host_wide_int__;
 # if HOST_BITS_PER_WIDE_INT == 64
 #  define HOST_WIDE_INT_PRINT_DOUBLE_HEX \
      "0x%" HOST_LONG_FORMAT "x%016" HOST_LONG_FORMAT "x"
+#  define HOST_WIDE_INT_PRINT_PADDED_HEX \
+     "%016" HOST_LONG_FORMAT "x"
 # else
 #  define HOST_WIDE_INT_PRINT_DOUBLE_HEX \
      "0x%" HOST_LONG_FORMAT "x%08" HOST_LONG_FORMAT "x"
+#  define HOST_WIDE_INT_PRINT_PADDED_HEX \
+     "%08" HOST_LONG_FORMAT "x"
 # endif
 #else
 # define HOST_WIDE_INT_PRINT HOST_LONG_LONG_FORMAT
@@ -104,6 +142,8 @@  typedef HOST_WIDE_INT __gcc_host_wide_int__;
   /* We can assume that 'long long' is at least 64 bits.  */
 # define HOST_WIDE_INT_PRINT_DOUBLE_HEX \
     "0x%" HOST_LONG_LONG_FORMAT "x%016" HOST_LONG_LONG_FORMAT "x"
+# define HOST_WIDE_INT_PRINT_PADDED_HEX \
+    "%016" HOST_LONG_LONG_FORMAT "x"
 #endif /* HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG */
 
 #define HOST_WIDE_INT_PRINT_DEC "%" HOST_WIDE_INT_PRINT "d"
@@ -277,4 +317,32 @@  extern HOST_WIDE_INT pos_mul_hwi (HOST_WIDE_INT, HOST_WIDE_INT);
 extern HOST_WIDE_INT mul_hwi (HOST_WIDE_INT, HOST_WIDE_INT);
 extern HOST_WIDE_INT least_common_multiple (HOST_WIDE_INT, HOST_WIDE_INT);
 
+/* Sign extend SRC starting from PREC.  */
+
+static inline HOST_WIDE_INT
+sext_hwi (HOST_WIDE_INT src, int prec)
+{
+  if (prec == HOST_BITS_PER_WIDE_INT)
+    return src;
+  else
+    {
+      int shift = HOST_BITS_PER_WIDE_INT - (prec & (HOST_BITS_PER_WIDE_INT - 1));
+      return (src << shift) >> shift;
+    }
+}
+
+/* Zero extend SRC starting from PREC.  */
+
+static inline HOST_WIDE_INT
+zext_hwi (HOST_WIDE_INT src, int prec)
+{
+  if (prec == HOST_BITS_PER_WIDE_INT)
+    return src;
+  else
+    return src & (((HOST_WIDE_INT)1
+		   << (prec & (HOST_BITS_PER_WIDE_INT - 1))) - 1);
+}
+
+
+
 #endif /* ! GCC_HWINT_H */