changed: small optimization in ttmath_subindexed_x64()

(asm for x86_64 on MS VC)
changed: removed some MS VC warnings
changed: if TTMATH_DEBUG_LOG is defined then UInt::UInt()
         constructor fills the table with special values
added:   macro: TTMATH_BITS(min_bits)
         which returns the number of machine words
         capable to hold min_bits bits


git-svn-id: svn://ttmath.org/publicrep/ttmath/trunk@201 e52654a7-88a9-db11-a3e9-0013d4bc506e

ttmath/ttmath.h

@@ -46,10 +46,13 @@
 */
 
 #ifdef _MSC_VER
-//warning C4127: conditional expression is constant
 #pragma warning( disable: 4127 )
+//warning C4127: conditional expression is constant
+#pragma warning( disable: 4702 )
+//warning C4702: unreachable code
 #endif
 
+
 #include "ttmathbig.h"
 #include "ttmathobjects.h"
 
@@ -2788,6 +2791,8 @@ namespace ttmath
 #ifdef _MSC_VER
 #pragma warning( default: 4127 )
 //warning C4127: conditional expression is constant
+#pragma warning( disable: 4702 )
+//warning C4702: unreachable code
 #endif
 
 #endif

ttmath/ttmathtypes.h

@@ -157,6 +157,13 @@ namespace ttmath
 	*/
 	#define TTMATH_BUILTIN_VARIABLES_SIZE 256u
 
+	/*!
+		this macro returns the number of machine words 
+		capable to hold min_bits bits
+		e.g. TTMATH_BITS(128) returns 4
+	*/
+	#define TTMATH_BITS(min_bits) ((min_bits-1)/32 + 1)
+
 #else
 
 	/*!
@@ -203,6 +210,13 @@ namespace ttmath
 	*/
 	#define TTMATH_BUILTIN_VARIABLES_SIZE 128ul
 
+	/*!
+		this macro returns the number of machine words 
+		capable to hold min_bits bits
+		e.g. TTMATH_BITS(128) returns 2
+	*/
+	#define TTMATH_BITS(min_bits) ((min_bits-1)/64 + 1)
+
 #endif
 }
 
@@ -279,6 +293,7 @@ namespace ttmath
 
 
 
+
 namespace ttmath
 {
 

ttmath/ttmathuint.h

@@ -2594,6 +2594,18 @@ public:
 	*/
 	UInt()
 	{
+	// when macro TTMATH_DEBUG_LOG is defined
+	// we set special values to the table
+	// in order to be everywhere the same value of the UInt object
+	#ifdef TTMATH_DEBUG_LOG
+		#ifdef TTMATH_PLATFORM32
+				for(uint i=0 ; i<value_size ; ++i)
+					table[i] = 0xc1c1c1c1;
+		#else
+				for(uint i=0 ; i<value_size ; ++i)
+					table[i] = 0xc1c1c1c1c1c1c1c1;
+		#endif
+	#endif
 	}
 
 

ttmath/ttmathuint_x86_64.h

@@ -390,7 +390,7 @@ namespace ttmath
 
 		#endif
 
-		TTMATH_LOG("UInt::AddVector")
+//		TTMATH_LOG("UInt::AddVector")
 
 	return c;
 	}
@@ -613,7 +613,7 @@ namespace ttmath
 
 		#endif
 
-		TTMATH_LOG("UInt::SubVector")
+//		TTMATH_LOG("UInt::SubVector")
 
 	return c;
 	}

ttmath/ttmathuint_x86_64_msvc.asm

@@ -44,11 +44,11 @@
 PUBLIC	ttmath_adc_x64
 PUBLIC	ttmath_addindexed_x64
 PUBLIC	ttmath_addindexed2_x64
-PUBLIC  ttmath_addvector_x64
+PUBLIC	ttmath_addvector_x64
 
 PUBLIC	ttmath_sbb_x64
 PUBLIC	ttmath_subindexed_x64
-PUBLIC  ttmath_subvector_x64
+PUBLIC	ttmath_subvector_x64
 
 PUBLIC	ttmath_rcl_x64
 PUBLIC	ttmath_rcr_x64
@@ -58,6 +58,8 @@ PUBLIC	ttmath_rcr2_x64
 
 PUBLIC	ttmath_div_x64
 
+;
+; Microsoft x86_64 convention: http://msdn.microsoft.com/en-us/library/9b372w95.aspx
 ;
 ;	"rax, rcx, rdx, r8-r11 are volatile."
 ;	"rbx, rbp, rdi, rsi, r12-r15 are nonvolatile."
@@ -289,16 +291,14 @@ loop1:
 		mov		r9, 1
 		dec		rdx
 		jnz		loop1
-		jc		return_1	; most of the times, there will be NO carry (I hope)
+
+		mov		rax, 1
+		ret
 
 done:
 		xor		rax, rax
 		ret
 
-  return_1:
-		mov		rax, 1
-		ret
-
 ttmath_subindexed_x64	ENDP