diff options
Diffstat (limited to 'freetype/include/internal/ftcalc.h')
| -rw-r--r-- | freetype/include/internal/ftcalc.h | 289 |
1 files changed, 262 insertions, 27 deletions
diff --git a/freetype/include/internal/ftcalc.h b/freetype/include/internal/ftcalc.h index 03bd68eb1..14ec37b9c 100644 --- a/freetype/include/internal/ftcalc.h +++ b/freetype/include/internal/ftcalc.h @@ -4,7 +4,7 @@ /* */ /* Arithmetic computations (specification). */ /* */ -/* Copyright 1996-2006, 2008, 2009, 2012-2013 by */ +/* Copyright 1996-2006, 2008, 2009, 2012-2014 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 ) |