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-rw-r--r--include/internal/ftcalc.h289
1 files changed, 262 insertions, 27 deletions
diff --git a/include/internal/ftcalc.h b/include/internal/ftcalc.h
index 03bd68e..75752c3 100644
--- a/include/internal/ftcalc.h
+++ b/include/internal/ftcalc.h
@@ -4,7 +4,7 @@
/* */
/* Arithmetic computations (specification). */
/* */
-/* Copyright 1996-2006, 2008, 2009, 2012-2013 by */
+/* Copyright 1996-2015 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
@@ -27,36 +27,223 @@
FT_BEGIN_HEADER
-#if 0
-
/*************************************************************************/
/* */
- /* <Function> */
- /* FT_SqrtFixed */
- /* */
- /* <Description> */
- /* Computes the square root of a 16.16 fixed-point value. */
- /* */
- /* <Input> */
- /* x :: The value to compute the root for. */
- /* */
- /* <Return> */
- /* The result of `sqrt(x)'. */
- /* */
- /* <Note> */
- /* This function is not very fast. */
+ /* FT_MulDiv() and FT_MulFix() are declared in freetype.h. */
/* */
- FT_BASE( FT_Int32 )
- FT_SqrtFixed( FT_Int32 x );
+ /*************************************************************************/
-#endif /* 0 */
+#ifndef FT_CONFIG_OPTION_NO_ASSEMBLER
+ /* Provide assembler fragments for performance-critical functions. */
+ /* These must be defined `static __inline__' with GCC. */
+#if defined( __CC_ARM ) || defined( __ARMCC__ ) /* RVCT */
- /*************************************************************************/
- /* */
- /* FT_MulDiv() and FT_MulFix() are declared in freetype.h. */
- /* */
- /*************************************************************************/
+#define FT_MULFIX_ASSEMBLER FT_MulFix_arm
+
+ /* documentation is in freetype.h */
+
+ static __inline FT_Int32
+ FT_MulFix_arm( FT_Int32 a,
+ FT_Int32 b )
+ {
+ register FT_Int32 t, t2;
+
+
+ __asm
+ {
+ smull t2, t, b, a /* (lo=t2,hi=t) = a*b */
+ mov a, t, asr #31 /* a = (hi >> 31) */
+ add a, a, #0x8000 /* a += 0x8000 */
+ adds t2, t2, a /* t2 += a */
+ adc t, t, #0 /* t += carry */
+ mov a, t2, lsr #16 /* a = t2 >> 16 */
+ orr a, a, t, lsl #16 /* a |= t << 16 */
+ }
+ return a;
+ }
+
+#endif /* __CC_ARM || __ARMCC__ */
+
+
+#ifdef __GNUC__
+
+#if defined( __arm__ ) && \
+ ( !defined( __thumb__ ) || defined( __thumb2__ ) ) && \
+ !( defined( __CC_ARM ) || defined( __ARMCC__ ) )
+
+#define FT_MULFIX_ASSEMBLER FT_MulFix_arm
+
+ /* documentation is in freetype.h */
+
+ static __inline__ FT_Int32
+ FT_MulFix_arm( FT_Int32 a,
+ FT_Int32 b )
+ {
+ register FT_Int32 t, t2;
+
+
+ __asm__ __volatile__ (
+ "smull %1, %2, %4, %3\n\t" /* (lo=%1,hi=%2) = a*b */
+ "mov %0, %2, asr #31\n\t" /* %0 = (hi >> 31) */
+#if defined( __clang__ ) && defined( __thumb2__ )
+ "add.w %0, %0, #0x8000\n\t" /* %0 += 0x8000 */
+#else
+ "add %0, %0, #0x8000\n\t" /* %0 += 0x8000 */
+#endif
+ "adds %1, %1, %0\n\t" /* %1 += %0 */
+ "adc %2, %2, #0\n\t" /* %2 += carry */
+ "mov %0, %1, lsr #16\n\t" /* %0 = %1 >> 16 */
+ "orr %0, %0, %2, lsl #16\n\t" /* %0 |= %2 << 16 */
+ : "=r"(a), "=&r"(t2), "=&r"(t)
+ : "r"(a), "r"(b)
+ : "cc" );
+ return a;
+ }
+
+#endif /* __arm__ && */
+ /* ( __thumb2__ || !__thumb__ ) && */
+ /* !( __CC_ARM || __ARMCC__ ) */
+
+
+#if defined( __i386__ )
+
+#define FT_MULFIX_ASSEMBLER FT_MulFix_i386
+
+ /* documentation is in freetype.h */
+
+ static __inline__ FT_Int32
+ FT_MulFix_i386( FT_Int32 a,
+ FT_Int32 b )
+ {
+ register FT_Int32 result;
+
+
+ __asm__ __volatile__ (
+ "imul %%edx\n"
+ "movl %%edx, %%ecx\n"
+ "sarl $31, %%ecx\n"
+ "addl $0x8000, %%ecx\n"
+ "addl %%ecx, %%eax\n"
+ "adcl $0, %%edx\n"
+ "shrl $16, %%eax\n"
+ "shll $16, %%edx\n"
+ "addl %%edx, %%eax\n"
+ : "=a"(result), "=d"(b)
+ : "a"(a), "d"(b)
+ : "%ecx", "cc" );
+ return result;
+ }
+
+#endif /* i386 */
+
+#endif /* __GNUC__ */
+
+
+#ifdef _MSC_VER /* Visual C++ */
+
+#ifdef _M_IX86
+
+#define FT_MULFIX_ASSEMBLER FT_MulFix_i386
+
+ /* documentation is in freetype.h */
+
+ static __inline FT_Int32
+ FT_MulFix_i386( FT_Int32 a,
+ FT_Int32 b )
+ {
+ register FT_Int32 result;
+
+ __asm
+ {
+ mov eax, a
+ mov edx, b
+ imul edx
+ mov ecx, edx
+ sar ecx, 31
+ add ecx, 8000h
+ add eax, ecx
+ adc edx, 0
+ shr eax, 16
+ shl edx, 16
+ add eax, edx
+ mov result, eax
+ }
+ return result;
+ }
+
+#endif /* _M_IX86 */
+
+#endif /* _MSC_VER */
+
+
+#if defined( __GNUC__ ) && defined( __x86_64__ )
+
+#define FT_MULFIX_ASSEMBLER FT_MulFix_x86_64
+
+ static __inline__ FT_Int32
+ FT_MulFix_x86_64( FT_Int32 a,
+ FT_Int32 b )
+ {
+ /* Temporarily disable the warning that C90 doesn't support */
+ /* `long long'. */
+#if __GNUC__ > 4 || ( __GNUC__ == 4 && __GNUC_MINOR__ >= 6 )
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wlong-long"
+#endif
+
+#if 1
+ /* Technically not an assembly fragment, but GCC does a really good */
+ /* job at inlining it and generating good machine code for it. */
+ long long ret, tmp;
+
+
+ ret = (long long)a * b;
+ tmp = ret >> 63;
+ ret += 0x8000 + tmp;
+
+ return (FT_Int32)( ret >> 16 );
+#else
+
+ /* For some reason, GCC 4.6 on Ubuntu 12.04 generates invalid machine */
+ /* code from the lines below. The main issue is that `wide_a' is not */
+ /* properly initialized by sign-extending `a'. Instead, the generated */
+ /* machine code assumes that the register that contains `a' on input */
+ /* can be used directly as a 64-bit value, which is wrong most of the */
+ /* time. */
+ long long wide_a = (long long)a;
+ long long wide_b = (long long)b;
+ long long result;
+
+
+ __asm__ __volatile__ (
+ "imul %2, %1\n"
+ "mov %1, %0\n"
+ "sar $63, %0\n"
+ "lea 0x8000(%1, %0), %0\n"
+ "sar $16, %0\n"
+ : "=&r"(result), "=&r"(wide_a)
+ : "r"(wide_b)
+ : "cc" );
+
+ return (FT_Int32)result;
+#endif
+
+#if __GNUC__ > 4 || ( __GNUC__ == 4 && __GNUC_MINOR__ >= 6 )
+#pragma GCC diagnostic pop
+#endif
+ }
+
+#endif /* __GNUC__ && __x86_64__ */
+
+#endif /* !FT_CONFIG_OPTION_NO_ASSEMBLER */
+
+
+#ifdef FT_CONFIG_OPTION_INLINE_MULFIX
+#ifdef FT_MULFIX_ASSEMBLER
+#define FT_MulFix( a, b ) FT_MULFIX_ASSEMBLER( (FT_Int32)(a), (FT_Int32)(b) )
+#endif
+#endif
/*************************************************************************/
@@ -124,10 +311,11 @@ FT_BEGIN_HEADER
FT_Pos out_x,
FT_Pos out_y );
+
/*
* Return TRUE if a corner is flat or nearly flat. This is equivalent to
- * saying that the angle difference between the `in' and `out' vectors is
- * very small.
+ * saying that the corner point is close to its neighbors, or inside an
+ * ellipse defined by the neighbor focal points to be more precise.
*/
FT_BASE( FT_Int )
ft_corner_is_flat( FT_Pos in_x,
@@ -139,9 +327,31 @@ FT_BEGIN_HEADER
/*
* Return the most significant bit index.
*/
+
+#ifndef FT_CONFIG_OPTION_NO_ASSEMBLER
+#if defined( __GNUC__ ) && \
+ ( __GNUC__ > 3 || ( __GNUC__ == 3 && __GNUC_MINOR__ >= 4 ) )
+
+#if FT_SIZEOF_INT == 4
+
+#define FT_MSB( x ) ( 31 - __builtin_clz( x ) )
+
+#elif FT_SIZEOF_LONG == 4
+
+#define FT_MSB( x ) ( 31 - __builtin_clzl( x ) )
+
+#endif
+
+#endif /* __GNUC__ */
+#endif /* !FT_CONFIG_OPTION_NO_ASSEMBLER */
+
+#ifndef FT_MSB
+
FT_BASE( FT_Int )
FT_MSB( FT_UInt32 z );
+#endif
+
/*
* Return sqrt(x*x+y*y), which is the same as `FT_Vector_Length' but uses
@@ -152,6 +362,31 @@ FT_BEGIN_HEADER
FT_Fixed y );
+#if 0
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* FT_SqrtFixed */
+ /* */
+ /* <Description> */
+ /* Computes the square root of a 16.16 fixed-point value. */
+ /* */
+ /* <Input> */
+ /* x :: The value to compute the root for. */
+ /* */
+ /* <Return> */
+ /* The result of `sqrt(x)'. */
+ /* */
+ /* <Note> */
+ /* This function is not very fast. */
+ /* */
+ FT_BASE( FT_Int32 )
+ FT_SqrtFixed( FT_Int32 x );
+
+#endif /* 0 */
+
+
#define INT_TO_F26DOT6( x ) ( (FT_Long)(x) << 6 )
#define INT_TO_F2DOT14( x ) ( (FT_Long)(x) << 14 )
#define INT_TO_FIXED( x ) ( (FT_Long)(x) << 16 )
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 05:10:28 +0000