diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-01-29 08:52:50 +1100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-01-29 08:52:50 +1100 |
commit | e189f3495c4e30fc84fc9241096edf3932e23439 (patch) | |
tree | 5916c89ace81537a02ae01869386ba6caafdab9c /arch/sh/kernel/cpu/sh4/softfloat.c | |
parent | f4798748dee00c807a63f5518f08b3df161e0f6d (diff) | |
parent | 6582d7b7376aa587d74b08c74457dc28abc1a9fa (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (197 commits)
sh: add spi header and r2d platform data V3
sh: update r7780rp interrupt code
sh: remove consistent alloc stuff from the machine vector
sh: use declared coherent memory for dreamcast pci ethernet adapter
sh: declared coherent memory support V2
sh: Add support for SDK7780 board.
sh: constify function pointer tables
sh: Kill off -traditional for linker script.
cdrom: Add support for Sega Dreamcast GD-ROM.
sh: Kill off hs7751rvoip reference from arch/sh/Kconfig.
sh: Drop r7780rp_defconfig, use r7780mp_defconfig as kbuild default.
sh: Kill off dead HS771RVoIP board support.
sh: r7785rp: Fix up DECLARE_INTC_DESC() arg mismatch.
sh: r7785rp: Hook up the rest of the HL7785 FPGA IRQ vectors.
sh: r2d - enable sm501 usb host function
sh: remove voyagergx
sh: r2d - add lcd planel timings to sm501 platform data
sh: Add OHCI and UDC platform devices for SH7720.
sh: intc - remove default interrupt priority tables
sh: Correct pte size mismatch for X2 TLB.
...
Diffstat (limited to 'arch/sh/kernel/cpu/sh4/softfloat.c')
-rw-r--r-- | arch/sh/kernel/cpu/sh4/softfloat.c | 892 |
1 files changed, 892 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/sh4/softfloat.c b/arch/sh/kernel/cpu/sh4/softfloat.c new file mode 100644 index 00000000000..7b2d337ee41 --- /dev/null +++ b/arch/sh/kernel/cpu/sh4/softfloat.c @@ -0,0 +1,892 @@ +/* + * Floating point emulation support for subnormalised numbers on SH4 + * architecture This file is derived from the SoftFloat IEC/IEEE + * Floating-point Arithmetic Package, Release 2 the original license of + * which is reproduced below. + * + * ======================================================================== + * + * This C source file is part of the SoftFloat IEC/IEEE Floating-point + * Arithmetic Package, Release 2. + * + * Written by John R. Hauser. This work was made possible in part by the + * International Computer Science Institute, located at Suite 600, 1947 Center + * Street, Berkeley, California 94704. Funding was partially provided by the + * National Science Foundation under grant MIP-9311980. The original version + * of this code was written as part of a project to build a fixed-point vector + * processor in collaboration with the University of California at Berkeley, + * overseen by Profs. Nelson Morgan and John Wawrzynek. More information + * is available through the web page `http://HTTP.CS.Berkeley.EDU/~jhauser/ + * arithmetic/softfloat.html'. + * + * THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort + * has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT + * TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO + * PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY + * AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE. + * + * Derivative works are acceptable, even for commercial purposes, so long as + * (1) they include prominent notice that the work is derivative, and (2) they + * include prominent notice akin to these three paragraphs for those parts of + * this code that are retained. + * + * ======================================================================== + * + * SH4 modifications by Ismail Dhaoui <ismail.dhaoui@st.com> + * and Kamel Khelifi <kamel.khelifi@st.com> + */ +#include <linux/kernel.h> +#include <asm/cpu/fpu.h> + +#define LIT64( a ) a##LL + +typedef char flag; +typedef unsigned char uint8; +typedef signed char int8; +typedef int uint16; +typedef int int16; +typedef unsigned int uint32; +typedef signed int int32; + +typedef unsigned long long int bits64; +typedef signed long long int sbits64; + +typedef unsigned char bits8; +typedef signed char sbits8; +typedef unsigned short int bits16; +typedef signed short int sbits16; +typedef unsigned int bits32; +typedef signed int sbits32; + +typedef unsigned long long int uint64; +typedef signed long long int int64; + +typedef unsigned long int float32; +typedef unsigned long long float64; + +extern void float_raise(unsigned int flags); /* in fpu.c */ +extern int float_rounding_mode(void); /* in fpu.c */ + +inline bits64 extractFloat64Frac(float64 a); +inline flag extractFloat64Sign(float64 a); +inline int16 extractFloat64Exp(float64 a); +inline int16 extractFloat32Exp(float32 a); +inline flag extractFloat32Sign(float32 a); +inline bits32 extractFloat32Frac(float32 a); +inline float64 packFloat64(flag zSign, int16 zExp, bits64 zSig); +inline void shift64RightJamming(bits64 a, int16 count, bits64 * zPtr); +inline float32 packFloat32(flag zSign, int16 zExp, bits32 zSig); +inline void shift32RightJamming(bits32 a, int16 count, bits32 * zPtr); +float64 float64_sub(float64 a, float64 b); +float32 float32_sub(float32 a, float32 b); +float32 float32_add(float32 a, float32 b); +float64 float64_add(float64 a, float64 b); +float64 float64_div(float64 a, float64 b); +float32 float32_div(float32 a, float32 b); +float32 float32_mul(float32 a, float32 b); +float64 float64_mul(float64 a, float64 b); +inline void add128(bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 * z0Ptr, + bits64 * z1Ptr); +inline void sub128(bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 * z0Ptr, + bits64 * z1Ptr); +inline void mul64To128(bits64 a, bits64 b, bits64 * z0Ptr, bits64 * z1Ptr); + +static int8 countLeadingZeros32(bits32 a); +static int8 countLeadingZeros64(bits64 a); +static float64 normalizeRoundAndPackFloat64(flag zSign, int16 zExp, + bits64 zSig); +static float64 subFloat64Sigs(float64 a, float64 b, flag zSign); +static float64 addFloat64Sigs(float64 a, float64 b, flag zSign); +static float32 roundAndPackFloat32(flag zSign, int16 zExp, bits32 zSig); +static float32 normalizeRoundAndPackFloat32(flag zSign, int16 zExp, + bits32 zSig); +static float64 roundAndPackFloat64(flag zSign, int16 zExp, bits64 zSig); +static float32 subFloat32Sigs(float32 a, float32 b, flag zSign); +static float32 addFloat32Sigs(float32 a, float32 b, flag zSign); +static void normalizeFloat64Subnormal(bits64 aSig, int16 * zExpPtr, + bits64 * zSigPtr); +static bits64 estimateDiv128To64(bits64 a0, bits64 a1, bits64 b); +static void normalizeFloat32Subnormal(bits32 aSig, int16 * zExpPtr, + bits32 * zSigPtr); + +inline bits64 extractFloat64Frac(float64 a) +{ + return a & LIT64(0x000FFFFFFFFFFFFF); +} + +inline flag extractFloat64Sign(float64 a) +{ + return a >> 63; +} + +inline int16 extractFloat64Exp(float64 a) +{ + return (a >> 52) & 0x7FF; +} + +inline int16 extractFloat32Exp(float32 a) +{ + return (a >> 23) & 0xFF; +} + +inline flag extractFloat32Sign(float32 a) +{ + return a >> 31; +} + +inline bits32 extractFloat32Frac(float32 a) +{ + return a & 0x007FFFFF; +} + +inline float64 packFloat64(flag zSign, int16 zExp, bits64 zSig) +{ + return (((bits64) zSign) << 63) + (((bits64) zExp) << 52) + zSig; +} + +inline void shift64RightJamming(bits64 a, int16 count, bits64 * zPtr) +{ + bits64 z; + + if (count == 0) { + z = a; + } else if (count < 64) { + z = (a >> count) | ((a << ((-count) & 63)) != 0); + } else { + z = (a != 0); + } + *zPtr = z; +} + +static int8 countLeadingZeros32(bits32 a) +{ + static const int8 countLeadingZerosHigh[] = { + 8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, + 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, + 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, + 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 + }; + int8 shiftCount; + + shiftCount = 0; + if (a < 0x10000) { + shiftCount += 16; + a <<= 16; + } + if (a < 0x1000000) { + shiftCount += 8; + a <<= 8; + } + shiftCount += countLeadingZerosHigh[a >> 24]; + return shiftCount; + +} + +static int8 countLeadingZeros64(bits64 a) +{ + int8 shiftCount; + + shiftCount = 0; + if (a < ((bits64) 1) << 32) { + shiftCount += 32; + } else { + a >>= 32; + } + shiftCount += countLeadingZeros32(a); + return shiftCount; + +} + +static float64 normalizeRoundAndPackFloat64(flag zSign, int16 zExp, bits64 zSig) +{ + int8 shiftCount; + + shiftCount = countLeadingZeros64(zSig) - 1; + return roundAndPackFloat64(zSign, zExp - shiftCount, + zSig << shiftCount); + +} + +static float64 subFloat64Sigs(float64 a, float64 b, flag zSign) +{ + int16 aExp, bExp, zExp; + bits64 aSig, bSig, zSig; + int16 expDiff; + + aSig = extractFloat64Frac(a); + aExp = extractFloat64Exp(a); + bSig = extractFloat64Frac(b); + bExp = extractFloat64Exp(b); + expDiff = aExp - bExp; + aSig <<= 10; + bSig <<= 10; + if (0 < expDiff) + goto aExpBigger; + if (expDiff < 0) + goto bExpBigger; + if (aExp == 0) { + aExp = 1; + bExp = 1; + } + if (bSig < aSig) + goto aBigger; + if (aSig < bSig) + goto bBigger; + return packFloat64(float_rounding_mode() == FPSCR_RM_ZERO, 0, 0); + bExpBigger: + if (bExp == 0x7FF) { + return packFloat64(zSign ^ 1, 0x7FF, 0); + } + if (aExp == 0) { + ++expDiff; + } else { + aSig |= LIT64(0x4000000000000000); + } + shift64RightJamming(aSig, -expDiff, &aSig); + bSig |= LIT64(0x4000000000000000); + bBigger: + zSig = bSig - aSig; + zExp = bExp; + zSign ^= 1; + goto normalizeRoundAndPack; + aExpBigger: + if (aExp == 0x7FF) { + return a; + } + if (bExp == 0) { + --expDiff; + } else { + bSig |= LIT64(0x4000000000000000); + } + shift64RightJamming(bSig, expDiff, &bSig); + aSig |= LIT64(0x4000000000000000); + aBigger: + zSig = aSig - bSig; + zExp = aExp; + normalizeRoundAndPack: + --zExp; + return normalizeRoundAndPackFloat64(zSign, zExp, zSig); + +} +static float64 addFloat64Sigs(float64 a, float64 b, flag zSign) +{ + int16 aExp, bExp, zExp; + bits64 aSig, bSig, zSig; + int16 expDiff; + + aSig = extractFloat64Frac(a); + aExp = extractFloat64Exp(a); + bSig = extractFloat64Frac(b); + bExp = extractFloat64Exp(b); + expDiff = aExp - bExp; + aSig <<= 9; + bSig <<= 9; + if (0 < expDiff) { + if (aExp == 0x7FF) { + return a; + } + if (bExp == 0) { + --expDiff; + } else { + bSig |= LIT64(0x2000000000000000); + } + shift64RightJamming(bSig, expDiff, &bSig); + zExp = aExp; + } else if (expDiff < 0) { + if (bExp == 0x7FF) { + return packFloat64(zSign, 0x7FF, 0); + } + if (aExp == 0) { + ++expDiff; + } else { + aSig |= LIT64(0x2000000000000000); + } + shift64RightJamming(aSig, -expDiff, &aSig); + zExp = bExp; + } else { + if (aExp == 0x7FF) { + return a; + } + if (aExp == 0) + return packFloat64(zSign, 0, (aSig + bSig) >> 9); + zSig = LIT64(0x4000000000000000) + aSig + bSig; + zExp = aExp; + goto roundAndPack; + } + aSig |= LIT64(0x2000000000000000); + zSig = (aSig + bSig) << 1; + --zExp; + if ((sbits64) zSig < 0) { + zSig = aSig + bSig; + ++zExp; + } + roundAndPack: + return roundAndPackFloat64(zSign, zExp, zSig); + +} + +inline float32 packFloat32(flag zSign, int16 zExp, bits32 zSig) +{ + return (((bits32) zSign) << 31) + (((bits32) zExp) << 23) + zSig; +} + +inline void shift32RightJamming(bits32 a, int16 count, bits32 * zPtr) +{ + bits32 z; + if (count == 0) { + z = a; + } else if (count < 32) { + z = (a >> count) | ((a << ((-count) & 31)) != 0); + } else { + z = (a != 0); + } + *zPtr = z; +} + +static float32 roundAndPackFloat32(flag zSign, int16 zExp, bits32 zSig) +{ + flag roundNearestEven; + int8 roundIncrement, roundBits; + flag isTiny; + + /* SH4 has only 2 rounding modes - round to nearest and round to zero */ + roundNearestEven = (float_rounding_mode() == FPSCR_RM_NEAREST); + roundIncrement = 0x40; + if (!roundNearestEven) { + roundIncrement = 0; + } + roundBits = zSig & 0x7F; + if (0xFD <= (bits16) zExp) { + if ((0xFD < zExp) + || ((zExp == 0xFD) + && ((sbits32) (zSig + roundIncrement) < 0)) + ) { + float_raise(FPSCR_CAUSE_OVERFLOW | FPSCR_CAUSE_INEXACT); + return packFloat32(zSign, 0xFF, + 0) - (roundIncrement == 0); + } + if (zExp < 0) { + isTiny = (zExp < -1) + || (zSig + roundIncrement < 0x80000000); + shift32RightJamming(zSig, -zExp, &zSig); + zExp = 0; + roundBits = zSig & 0x7F; + if (isTiny && roundBits) + float_raise(FPSCR_CAUSE_UNDERFLOW); + } + } + if (roundBits) + float_raise(FPSCR_CAUSE_INEXACT); + zSig = (zSig + roundIncrement) >> 7; + zSig &= ~(((roundBits ^ 0x40) == 0) & roundNearestEven); + if (zSig == 0) + zExp = 0; + return packFloat32(zSign, zExp, zSig); + +} + +static float32 normalizeRoundAndPackFloat32(flag zSign, int16 zExp, bits32 zSig) +{ + int8 shiftCount; + + shiftCount = countLeadingZeros32(zSig) - 1; + return roundAndPackFloat32(zSign, zExp - shiftCount, + zSig << shiftCount); +} + +static float64 roundAndPackFloat64(flag zSign, int16 zExp, bits64 zSig) +{ + flag roundNearestEven; + int16 roundIncrement, roundBits; + flag isTiny; + + /* SH4 has only 2 rounding modes - round to nearest and round to zero */ + roundNearestEven = (float_rounding_mode() == FPSCR_RM_NEAREST); + roundIncrement = 0x200; + if (!roundNearestEven) { + roundIncrement = 0; + } + roundBits = zSig & 0x3FF; + if (0x7FD <= (bits16) zExp) { + if ((0x7FD < zExp) + || ((zExp == 0x7FD) + && ((sbits64) (zSig + roundIncrement) < 0)) + ) { + float_raise(FPSCR_CAUSE_OVERFLOW | FPSCR_CAUSE_INEXACT); + return packFloat64(zSign, 0x7FF, + 0) - (roundIncrement == 0); + } + if (zExp < 0) { + isTiny = (zExp < -1) + || (zSig + roundIncrement < + LIT64(0x8000000000000000)); + shift64RightJamming(zSig, -zExp, &zSig); + zExp = 0; + roundBits = zSig & 0x3FF; + if (isTiny && roundBits) + float_raise(FPSCR_CAUSE_UNDERFLOW); + } + } + if (roundBits) + float_raise(FPSCR_CAUSE_INEXACT); + zSig = (zSig + roundIncrement) >> 10; + zSig &= ~(((roundBits ^ 0x200) == 0) & roundNearestEven); + if (zSig == 0) + zExp = 0; + return packFloat64(zSign, zExp, zSig); + +} + +static float32 subFloat32Sigs(float32 a, float32 b, flag zSign) +{ + int16 aExp, bExp, zExp; + bits32 aSig, bSig, zSig; + int16 expDiff; + + aSig = extractFloat32Frac(a); + aExp = extractFloat32Exp(a); + bSig = extractFloat32Frac(b); + bExp = extractFloat32Exp(b); + expDiff = aExp - bExp; + aSig <<= 7; + bSig <<= 7; + if (0 < expDiff) + goto aExpBigger; + if (expDiff < 0) + goto bExpBigger; + if (aExp == 0) { + aExp = 1; + bExp = 1; + } + if (bSig < aSig) + goto aBigger; + if (aSig < bSig) + goto bBigger; + return packFloat32(float_rounding_mode() == FPSCR_RM_ZERO, 0, 0); + bExpBigger: + if (bExp == 0xFF) { + return packFloat32(zSign ^ 1, 0xFF, 0); + } + if (aExp == 0) { + ++expDiff; + } else { + aSig |= 0x40000000; + } + shift32RightJamming(aSig, -expDiff, &aSig); + bSig |= 0x40000000; + bBigger: + zSig = bSig - aSig; + zExp = bExp; + zSign ^= 1; + goto normalizeRoundAndPack; + aExpBigger: + if (aExp == 0xFF) { + return a; + } + if (bExp == 0) { + --expDiff; + } else { + bSig |= 0x40000000; + } + shift32RightJamming(bSig, expDiff, &bSig); + aSig |= 0x40000000; + aBigger: + zSig = aSig - bSig; + zExp = aExp; + normalizeRoundAndPack: + --zExp; + return normalizeRoundAndPackFloat32(zSign, zExp, zSig); + +} + +static float32 addFloat32Sigs(float32 a, float32 b, flag zSign) +{ + int16 aExp, bExp, zExp; + bits32 aSig, bSig, zSig; + int16 expDiff; + + aSig = extractFloat32Frac(a); + aExp = extractFloat32Exp(a); + bSig = extractFloat32Frac(b); + bExp = extractFloat32Exp(b); + expDiff = aExp - bExp; + aSig <<= 6; + bSig <<= 6; + if (0 < expDiff) { + if (aExp == 0xFF) { + return a; + } + if (bExp == 0) { + --expDiff; + } else { + bSig |= 0x20000000; + } + shift32RightJamming(bSig, expDiff, &bSig); + zExp = aExp; + } else if (expDiff < 0) { + if (bExp == 0xFF) { + return packFloat32(zSign, 0xFF, 0); + } + if (aExp == 0) { + ++expDiff; + } else { + aSig |= 0x20000000; + } + shift32RightJamming(aSig, -expDiff, &aSig); + zExp = bExp; + } else { + if (aExp == 0xFF) { + return a; + } + if (aExp == 0) + return packFloat32(zSign, 0, (aSig + bSig) >> 6); + zSig = 0x40000000 + aSig + bSig; + zExp = aExp; + goto roundAndPack; + } + aSig |= 0x20000000; + zSig = (aSig + bSig) << 1; + --zExp; + if ((sbits32) zSig < 0) { + zSig = aSig + bSig; + ++zExp; + } + roundAndPack: + return roundAndPackFloat32(zSign, zExp, zSig); + +} + +float64 float64_sub(float64 a, float64 b) +{ + flag aSign, bSign; + + aSign = extractFloat64Sign(a); + bSign = extractFloat64Sign(b); + if (aSign == bSign) { + return subFloat64Sigs(a, b, aSign); + } else { + return addFloat64Sigs(a, b, aSign); + } + +} + +float32 float32_sub(float32 a, float32 b) +{ + flag aSign, bSign; + + aSign = extractFloat32Sign(a); + bSign = extractFloat32Sign(b); + if (aSign == bSign) { + return subFloat32Sigs(a, b, aSign); + } else { + return addFloat32Sigs(a, b, aSign); + } + +} + +float32 float32_add(float32 a, float32 b) +{ + flag aSign, bSign; + + aSign = extractFloat32Sign(a); + bSign = extractFloat32Sign(b); + if (aSign == bSign) { + return addFloat32Sigs(a, b, aSign); + } else { + return subFloat32Sigs(a, b, aSign); + } + +} + +float64 float64_add(float64 a, float64 b) +{ + flag aSign, bSign; + + aSign = extractFloat64Sign(a); + bSign = extractFloat64Sign(b); + if (aSign == bSign) { + return addFloat64Sigs(a, b, aSign); + } else { + return subFloat64Sigs(a, b, aSign); + } +} + +static void +normalizeFloat64Subnormal(bits64 aSig, int16 * zExpPtr, bits64 * zSigPtr) +{ + int8 shiftCount; + + shiftCount = countLeadingZeros64(aSig) - 11; + *zSigPtr = aSig << shiftCount; + *zExpPtr = 1 - shiftCount; +} + +inline void add128(bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 * z0Ptr, + bits64 * z1Ptr) +{ + bits64 z1; + + z1 = a1 + b1; + *z1Ptr = z1; + *z0Ptr = a0 + b0 + (z1 < a1); +} + +inline void +sub128(bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 * z0Ptr, + bits64 * z1Ptr) +{ + *z1Ptr = a1 - b1; + *z0Ptr = a0 - b0 - (a1 < b1); +} + +static bits64 estimateDiv128To64(bits64 a0, bits64 a1, bits64 b) +{ + bits64 b0, b1; + bits64 rem0, rem1, term0, term1; + bits64 z; + if (b <= a0) + return LIT64(0xFFFFFFFFFFFFFFFF); + b0 = b >> 32; + z = (b0 << 32 <= a0) ? LIT64(0xFFFFFFFF00000000) : (a0 / b0) << 32; + mul64To128(b, z, &term0, &term1); + sub128(a0, a1, term0, term1, &rem0, &rem1); + while (((sbits64) rem0) < 0) { + z -= LIT64(0x100000000); + b1 = b << 32; + add128(rem0, rem1, b0, b1, &rem0, &rem1); + } + rem0 = (rem0 << 32) | (rem1 >> 32); + z |= (b0 << 32 <= rem0) ? 0xFFFFFFFF : rem0 / b0; + return z; +} + +inline void mul64To128(bits64 a, bits64 b, bits64 * z0Ptr, bits64 * z1Ptr) +{ + bits32 aHigh, aLow, bHigh, bLow; + bits64 z0, zMiddleA, zMiddleB, z1; + + aLow = a; + aHigh = a >> 32; + bLow = b; + bHigh = b >> 32; + z1 = ((bits64) aLow) * bLow; + zMiddleA = ((bits64) aLow) * bHigh; + zMiddleB = ((bits64) aHigh) * bLow; + z0 = ((bits64) aHigh) * bHigh; + zMiddleA += zMiddleB; + z0 += (((bits64) (zMiddleA < zMiddleB)) << 32) + (zMiddleA >> 32); + zMiddleA <<= 32; + z1 += zMiddleA; + z0 += (z1 < zMiddleA); + *z1Ptr = z1; + *z0Ptr = z0; + +} + +static void normalizeFloat32Subnormal(bits32 aSig, int16 * zExpPtr, + bits32 * zSigPtr) +{ + int8 shiftCount; + + shiftCount = countLeadingZeros32(aSig) - 8; + *zSigPtr = aSig << shiftCount; + *zExpPtr = 1 - shiftCount; + +} + +float64 float64_div(float64 a, float64 b) +{ + flag aSign, bSign, zSign; + int16 aExp, bExp, zExp; + bits64 aSig, bSig, zSig; + bits64 rem0, rem1; + bits64 term0, term1; + + aSig = extractFloat64Frac(a); + aExp = extractFloat64Exp(a); + aSign = extractFloat64Sign(a); + bSig = extractFloat64Frac(b); + bExp = extractFloat64Exp(b); + bSign = extractFloat64Sign(b); + zSign = aSign ^ bSign; + if (aExp == 0x7FF) { + if (bExp == 0x7FF) { + } + return packFloat64(zSign, 0x7FF, 0); + } + if (bExp == 0x7FF) { + return packFloat64(zSign, 0, 0); + } + if (bExp == 0) { + if (bSig == 0) { + if ((aExp | aSig) == 0) { + float_raise(FPSCR_CAUSE_INVALID); + } + return packFloat64(zSign, 0x7FF, 0); + } + normalizeFloat64Subnormal(bSig, &bExp, &bSig); + } + if (aExp == 0) { + if (aSig == 0) + return packFloat64(zSign, 0, 0); + normalizeFloat64Subnormal(aSig, &aExp, &aSig); + } + zExp = aExp - bExp + 0x3FD; + aSig = (aSig | LIT64(0x0010000000000000)) << 10; + bSig = (bSig | LIT64(0x0010000000000000)) << 11; + if (bSig <= (aSig + aSig)) { + aSig >>= 1; + ++zExp; + } + zSig = estimateDiv128To64(aSig, 0, bSig); + if ((zSig & 0x1FF) <= 2) { + mul64To128(bSig, zSig, &term0, &term1); + sub128(aSig, 0, term0, term1, &rem0, &rem1); + while ((sbits64) rem0 < 0) { + --zSig; + add128(rem0, rem1, 0, bSig, &rem0, &rem1); + } + zSig |= (rem1 != 0); + } + return roundAndPackFloat64(zSign, zExp, zSig); + +} + +float32 float32_div(float32 a, float32 b) +{ + flag aSign, bSign, zSign; + int16 aExp, bExp, zExp; + bits32 aSig, bSig, zSig; + + aSig = extractFloat32Frac(a); + aExp = extractFloat32Exp(a); + aSign = extractFloat32Sign(a); + bSig = extractFloat32Frac(b); + bExp = extractFloat32Exp(b); + bSign = extractFloat32Sign(b); + zSign = aSign ^ bSign; + if (aExp == 0xFF) { + if (bExp == 0xFF) { + } + return packFloat32(zSign, 0xFF, 0); + } + if (bExp == 0xFF) { + return packFloat32(zSign, 0, 0); + } + if (bExp == 0) { + if (bSig == 0) { + return packFloat32(zSign, 0xFF, 0); + } + normalizeFloat32Subnormal(bSig, &bExp, &bSig); + } + if (aExp == 0) { + if (aSig == 0) + return packFloat32(zSign, 0, 0); + normalizeFloat32Subnormal(aSig, &aExp, &aSig); + } + zExp = aExp - bExp + 0x7D; + aSig = (aSig | 0x00800000) << 7; + bSig = (bSig | 0x00800000) << 8; + if (bSig <= (aSig + aSig)) { + aSig >>= 1; + ++zExp; + } + zSig = (((bits64) aSig) << 32) / bSig; + if ((zSig & 0x3F) == 0) { + zSig |= (((bits64) bSig) * zSig != ((bits64) aSig) << 32); + } + return roundAndPackFloat32(zSign, zExp, zSig); + +} + +float32 float32_mul(float32 a, float32 b) +{ + char aSign, bSign, zSign; + int aExp, bExp, zExp; + unsigned int aSig, bSig; + unsigned long long zSig64; + unsigned int zSig; + + aSig = extractFloat32Frac(a); + aExp = extractFloat32Exp(a); + aSign = extractFloat32Sign(a); + bSig = extractFloat32Frac(b); + bExp = extractFloat32Exp(b); + bSign = extractFloat32Sign(b); + zSign = aSign ^ bSign; + if (aExp == 0) { + if (aSig == 0) + return packFloat32(zSign, 0, 0); + normalizeFloat32Subnormal(aSig, &aExp, &aSig); + } + if (bExp == 0) { + if (bSig == 0) + return packFloat32(zSign, 0, 0); + normalizeFloat32Subnormal(bSig, &bExp, &bSig); + } + if ((bExp == 0xff && bSig == 0) || (aExp == 0xff && aSig == 0)) + return roundAndPackFloat32(zSign, 0xff, 0); + + zExp = aExp + bExp - 0x7F; + aSig = (aSig | 0x00800000) << 7; + bSig = (bSig | 0x00800000) << 8; + shift64RightJamming(((unsigned long long)aSig) * bSig, 32, &zSig64); + zSig = zSig64; + if (0 <= (signed int)(zSig << 1)) { + zSig <<= 1; + --zExp; + } + return roundAndPackFloat32(zSign, zExp, zSig); + +} + +float64 float64_mul(float64 a, float64 b) +{ + char aSign, bSign, zSign; + int aExp, bExp, zExp; + unsigned long long int aSig, bSig, zSig0, zSig1; + + aSig = extractFloat64Frac(a); + aExp = extractFloat64Exp(a); + aSign = extractFloat64Sign(a); + bSig = extractFloat64Frac(b); + bExp = extractFloat64Exp(b); + bSign = extractFloat64Sign(b); + zSign = aSign ^ bSign; + + if (aExp == 0) { + if (aSig == 0) + return packFloat64(zSign, 0, 0); + normalizeFloat64Subnormal(aSig, &aExp, &aSig); + } + if (bExp == 0) { + if (bSig == 0) + return packFloat64(zSign, 0, 0); + normalizeFloat64Subnormal(bSig, &bExp, &bSig); + } + if ((aExp == 0x7ff && aSig == 0) || (bExp == 0x7ff && bSig == 0)) + return roundAndPackFloat64(zSign, 0x7ff, 0); + + zExp = aExp + bExp - 0x3FF; + aSig = (aSig | 0x0010000000000000LL) << 10; + bSig = (bSig | 0x0010000000000000LL) << 11; + mul64To128(aSig, bSig, &zSig0, &zSig1); + zSig0 |= (zSig1 != 0); + if (0 <= (signed long long int)(zSig0 << 1)) { + zSig0 <<= 1; + --zExp; + } + return roundAndPackFloat64(zSign, zExp, zSig0); +} |