Restoring authorship annotation for Anton Samokhvalov <pg83@yandex.ru>. Commit 1 of 2.

1 files changed, 203 insertions, 203 deletions

diff --git a/contrib/libs/cxxsupp/builtins/divtf3.c b/contrib/libs/cxxsupp/builtins/divtf3.c
index e81dab826b..80471b381d 100644
--- a/contrib/libs/cxxsupp/builtins/divtf3.c
+++ b/contrib/libs/cxxsupp/builtins/divtf3.c
@@ -1,203 +1,203 @@
-//===-- lib/divtf3.c - Quad-precision division --------------------*- C -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements quad-precision soft-float division
-// with the IEEE-754 default rounding (to nearest, ties to even).
-//
-// For simplicity, this implementation currently flushes denormals to zero.
-// It should be a fairly straightforward exercise to implement gradual
-// underflow with correct rounding.
-//
-//===----------------------------------------------------------------------===//
-
-#define QUAD_PRECISION
-#include "fp_lib.h"
-
-#if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT)
-COMPILER_RT_ABI fp_t __divtf3(fp_t a, fp_t b) {
-
-    const unsigned int aExponent = toRep(a) >> significandBits & maxExponent;
-    const unsigned int bExponent = toRep(b) >> significandBits & maxExponent;
-    const rep_t quotientSign = (toRep(a) ^ toRep(b)) & signBit;
-
-    rep_t aSignificand = toRep(a) & significandMask;
-    rep_t bSignificand = toRep(b) & significandMask;
-    int scale = 0;
-
-    // Detect if a or b is zero, denormal, infinity, or NaN.
-    if (aExponent-1U >= maxExponent-1U || bExponent-1U >= maxExponent-1U) {
-
-        const rep_t aAbs = toRep(a) & absMask;
-        const rep_t bAbs = toRep(b) & absMask;
-
-        // NaN / anything = qNaN
-        if (aAbs > infRep) return fromRep(toRep(a) | quietBit);
-        // anything / NaN = qNaN
-        if (bAbs > infRep) return fromRep(toRep(b) | quietBit);
-
-        if (aAbs == infRep) {
-            // infinity / infinity = NaN
-            if (bAbs == infRep) return fromRep(qnanRep);
-            // infinity / anything else = +/- infinity
-            else return fromRep(aAbs | quotientSign);
-        }
-
-        // anything else / infinity = +/- 0
-        if (bAbs == infRep) return fromRep(quotientSign);
-
-        if (!aAbs) {
-            // zero / zero = NaN
-            if (!bAbs) return fromRep(qnanRep);
-            // zero / anything else = +/- zero
-            else return fromRep(quotientSign);
-        }
-        // anything else / zero = +/- infinity
-        if (!bAbs) return fromRep(infRep | quotientSign);
-
-        // one or both of a or b is denormal, the other (if applicable) is a
-        // normal number.  Renormalize one or both of a and b, and set scale to
-        // include the necessary exponent adjustment.
-        if (aAbs < implicitBit) scale += normalize(&aSignificand);
-        if (bAbs < implicitBit) scale -= normalize(&bSignificand);
-    }
-
-    // Or in the implicit significand bit.  (If we fell through from the
-    // denormal path it was already set by normalize( ), but setting it twice
-    // won't hurt anything.)
-    aSignificand |= implicitBit;
-    bSignificand |= implicitBit;
-    int quotientExponent = aExponent - bExponent + scale;
-
-    // Align the significand of b as a Q63 fixed-point number in the range
-    // [1, 2.0) and get a Q64 approximate reciprocal using a small minimax
-    // polynomial approximation: reciprocal = 3/4 + 1/sqrt(2) - b/2.  This
-    // is accurate to about 3.5 binary digits.
-    const uint64_t q63b = bSignificand >> 49;
-    uint64_t recip64 = UINT64_C(0x7504f333F9DE6484) - q63b;
-    // 0x7504f333F9DE6484 / 2^64 + 1 = 3/4 + 1/sqrt(2)
-
-    // Now refine the reciprocal estimate using a Newton-Raphson iteration:
-    //
-    //     x1 = x0 * (2 - x0 * b)
-    //
-    // This doubles the number of correct binary digits in the approximation
-    // with each iteration.
-    uint64_t correction64;
-    correction64 = -((rep_t)recip64 * q63b >> 64);
-    recip64 = (rep_t)recip64 * correction64 >> 63;
-    correction64 = -((rep_t)recip64 * q63b >> 64);
-    recip64 = (rep_t)recip64 * correction64 >> 63;
-    correction64 = -((rep_t)recip64 * q63b >> 64);
-    recip64 = (rep_t)recip64 * correction64 >> 63;
-    correction64 = -((rep_t)recip64 * q63b >> 64);
-    recip64 = (rep_t)recip64 * correction64 >> 63;
-    correction64 = -((rep_t)recip64 * q63b >> 64);
-    recip64 = (rep_t)recip64 * correction64 >> 63;
-
-    // recip64 might have overflowed to exactly zero in the preceeding
-    // computation if the high word of b is exactly 1.0.  This would sabotage
-    // the full-width final stage of the computation that follows, so we adjust
-    // recip64 downward by one bit.
-    recip64--;
-
-    // We need to perform one more iteration to get us to 112 binary digits;
-    // The last iteration needs to happen with extra precision.
-    const uint64_t q127blo = bSignificand << 15;
-    rep_t correction, reciprocal;
-
-    // NOTE: This operation is equivalent to __multi3, which is not implemented
-    //       in some architechure
-    rep_t r64q63, r64q127, r64cH, r64cL, dummy;
-    wideMultiply((rep_t)recip64, (rep_t)q63b, &dummy, &r64q63);
-    wideMultiply((rep_t)recip64, (rep_t)q127blo, &dummy, &r64q127);
-
-    correction = -(r64q63 + (r64q127 >> 64));
-
-    uint64_t cHi = correction >> 64;
-    uint64_t cLo = correction;
-
-    wideMultiply((rep_t)recip64, (rep_t)cHi, &dummy, &r64cH);
-    wideMultiply((rep_t)recip64, (rep_t)cLo, &dummy, &r64cL);
-
-    reciprocal = r64cH + (r64cL >> 64);
-
-    // We already adjusted the 64-bit estimate, now we need to adjust the final
-    // 128-bit reciprocal estimate downward to ensure that it is strictly smaller
-    // than the infinitely precise exact reciprocal.  Because the computation
-    // of the Newton-Raphson step is truncating at every step, this adjustment
-    // is small; most of the work is already done.
-    reciprocal -= 2;
-
-    // The numerical reciprocal is accurate to within 2^-112, lies in the
-    // interval [0.5, 1.0), and is strictly smaller than the true reciprocal
-    // of b.  Multiplying a by this reciprocal thus gives a numerical q = a/b
-    // in Q127 with the following properties:
-    //
-    //    1. q < a/b
-    //    2. q is in the interval [0.5, 2.0)
-    //    3. the error in q is bounded away from 2^-113 (actually, we have a
-    //       couple of bits to spare, but this is all we need).
-
-    // We need a 128 x 128 multiply high to compute q, which isn't a basic
-    // operation in C, so we need to be a little bit fussy.
-    rep_t quotient, quotientLo;
-    wideMultiply(aSignificand << 2, reciprocal, &quotient, &quotientLo);
-
-    // Two cases: quotient is in [0.5, 1.0) or quotient is in [1.0, 2.0).
-    // In either case, we are going to compute a residual of the form
-    //
-    //     r = a - q*b
-    //
-    // We know from the construction of q that r satisfies:
-    //
-    //     0 <= r < ulp(q)*b
-    //
-    // if r is greater than 1/2 ulp(q)*b, then q rounds up.  Otherwise, we
-    // already have the correct result.  The exact halfway case cannot occur.
-    // We also take this time to right shift quotient if it falls in the [1,2)
-    // range and adjust the exponent accordingly.
-    rep_t residual;
-    rep_t qb;
-
-    if (quotient < (implicitBit << 1)) {
-        wideMultiply(quotient, bSignificand, &dummy, &qb);
-        residual = (aSignificand << 113) - qb;
-        quotientExponent--;
-    } else {
-        quotient >>= 1;
-        wideMultiply(quotient, bSignificand, &dummy, &qb);
-        residual = (aSignificand << 112) - qb;
-    }
-
-    const int writtenExponent = quotientExponent + exponentBias;
-
-    if (writtenExponent >= maxExponent) {
-        // If we have overflowed the exponent, return infinity.
-        return fromRep(infRep | quotientSign);
-    }
-    else if (writtenExponent < 1) {
-        // Flush denormals to zero.  In the future, it would be nice to add
-        // code to round them correctly.
-        return fromRep(quotientSign);
-    }
-    else {
-        const bool round = (residual << 1) >= bSignificand;
-        // Clear the implicit bit
-        rep_t absResult = quotient & significandMask;
-        // Insert the exponent
-        absResult |= (rep_t)writtenExponent << significandBits;
-        // Round
-        absResult += round;
-        // Insert the sign and return
-        const long double result = fromRep(absResult | quotientSign);
-        return result;
-    }
-}
-
-#endif
+//===-- lib/divtf3.c - Quad-precision division --------------------*- C -*-===// 
+// 
+//                     The LLVM Compiler Infrastructure 
+// 
+// This file is dual licensed under the MIT and the University of Illinois Open 
+// Source Licenses. See LICENSE.TXT for details. 
+// 
+//===----------------------------------------------------------------------===// 
+// 
+// This file implements quad-precision soft-float division 
+// with the IEEE-754 default rounding (to nearest, ties to even). 
+// 
+// For simplicity, this implementation currently flushes denormals to zero. 
+// It should be a fairly straightforward exercise to implement gradual 
+// underflow with correct rounding. 
+// 
+//===----------------------------------------------------------------------===// 
+ 
+#define QUAD_PRECISION 
+#include "fp_lib.h" 
+ 
+#if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT) 
+COMPILER_RT_ABI fp_t __divtf3(fp_t a, fp_t b) { 
+ 
+    const unsigned int aExponent = toRep(a) >> significandBits & maxExponent; 
+    const unsigned int bExponent = toRep(b) >> significandBits & maxExponent; 
+    const rep_t quotientSign = (toRep(a) ^ toRep(b)) & signBit; 
+ 
+    rep_t aSignificand = toRep(a) & significandMask; 
+    rep_t bSignificand = toRep(b) & significandMask; 
+    int scale = 0; 
+ 
+    // Detect if a or b is zero, denormal, infinity, or NaN. 
+    if (aExponent-1U >= maxExponent-1U || bExponent-1U >= maxExponent-1U) { 
+ 
+        const rep_t aAbs = toRep(a) & absMask; 
+        const rep_t bAbs = toRep(b) & absMask; 
+ 
+        // NaN / anything = qNaN 
+        if (aAbs > infRep) return fromRep(toRep(a) | quietBit); 
+        // anything / NaN = qNaN 
+        if (bAbs > infRep) return fromRep(toRep(b) | quietBit); 
+ 
+        if (aAbs == infRep) { 
+            // infinity / infinity = NaN 
+            if (bAbs == infRep) return fromRep(qnanRep); 
+            // infinity / anything else = +/- infinity 
+            else return fromRep(aAbs | quotientSign); 
+        } 
+ 
+        // anything else / infinity = +/- 0 
+        if (bAbs == infRep) return fromRep(quotientSign); 
+ 
+        if (!aAbs) { 
+            // zero / zero = NaN 
+            if (!bAbs) return fromRep(qnanRep); 
+            // zero / anything else = +/- zero 
+            else return fromRep(quotientSign); 
+        } 
+        // anything else / zero = +/- infinity 
+        if (!bAbs) return fromRep(infRep | quotientSign); 
+ 
+        // one or both of a or b is denormal, the other (if applicable) is a 
+        // normal number.  Renormalize one or both of a and b, and set scale to 
+        // include the necessary exponent adjustment. 
+        if (aAbs < implicitBit) scale += normalize(&aSignificand); 
+        if (bAbs < implicitBit) scale -= normalize(&bSignificand); 
+    } 
+ 
+    // Or in the implicit significand bit.  (If we fell through from the 
+    // denormal path it was already set by normalize( ), but setting it twice 
+    // won't hurt anything.) 
+    aSignificand |= implicitBit; 
+    bSignificand |= implicitBit; 
+    int quotientExponent = aExponent - bExponent + scale; 
+ 
+    // Align the significand of b as a Q63 fixed-point number in the range 
+    // [1, 2.0) and get a Q64 approximate reciprocal using a small minimax 
+    // polynomial approximation: reciprocal = 3/4 + 1/sqrt(2) - b/2.  This 
+    // is accurate to about 3.5 binary digits. 
+    const uint64_t q63b = bSignificand >> 49; 
+    uint64_t recip64 = UINT64_C(0x7504f333F9DE6484) - q63b; 
+    // 0x7504f333F9DE6484 / 2^64 + 1 = 3/4 + 1/sqrt(2) 
+ 
+    // Now refine the reciprocal estimate using a Newton-Raphson iteration: 
+    // 
+    //     x1 = x0 * (2 - x0 * b) 
+    // 
+    // This doubles the number of correct binary digits in the approximation 
+    // with each iteration. 
+    uint64_t correction64; 
+    correction64 = -((rep_t)recip64 * q63b >> 64); 
+    recip64 = (rep_t)recip64 * correction64 >> 63; 
+    correction64 = -((rep_t)recip64 * q63b >> 64); 
+    recip64 = (rep_t)recip64 * correction64 >> 63; 
+    correction64 = -((rep_t)recip64 * q63b >> 64); 
+    recip64 = (rep_t)recip64 * correction64 >> 63; 
+    correction64 = -((rep_t)recip64 * q63b >> 64); 
+    recip64 = (rep_t)recip64 * correction64 >> 63; 
+    correction64 = -((rep_t)recip64 * q63b >> 64); 
+    recip64 = (rep_t)recip64 * correction64 >> 63; 
+ 
+    // recip64 might have overflowed to exactly zero in the preceeding 
+    // computation if the high word of b is exactly 1.0.  This would sabotage 
+    // the full-width final stage of the computation that follows, so we adjust 
+    // recip64 downward by one bit. 
+    recip64--; 
+ 
+    // We need to perform one more iteration to get us to 112 binary digits; 
+    // The last iteration needs to happen with extra precision. 
+    const uint64_t q127blo = bSignificand << 15; 
+    rep_t correction, reciprocal; 
+ 
+    // NOTE: This operation is equivalent to __multi3, which is not implemented 
+    //       in some architechure 
+    rep_t r64q63, r64q127, r64cH, r64cL, dummy; 
+    wideMultiply((rep_t)recip64, (rep_t)q63b, &dummy, &r64q63); 
+    wideMultiply((rep_t)recip64, (rep_t)q127blo, &dummy, &r64q127); 
+ 
+    correction = -(r64q63 + (r64q127 >> 64)); 
+ 
+    uint64_t cHi = correction >> 64; 
+    uint64_t cLo = correction; 
+ 
+    wideMultiply((rep_t)recip64, (rep_t)cHi, &dummy, &r64cH); 
+    wideMultiply((rep_t)recip64, (rep_t)cLo, &dummy, &r64cL); 
+ 
+    reciprocal = r64cH + (r64cL >> 64); 
+ 
+    // We already adjusted the 64-bit estimate, now we need to adjust the final 
+    // 128-bit reciprocal estimate downward to ensure that it is strictly smaller 
+    // than the infinitely precise exact reciprocal.  Because the computation 
+    // of the Newton-Raphson step is truncating at every step, this adjustment 
+    // is small; most of the work is already done. 
+    reciprocal -= 2; 
+ 
+    // The numerical reciprocal is accurate to within 2^-112, lies in the 
+    // interval [0.5, 1.0), and is strictly smaller than the true reciprocal 
+    // of b.  Multiplying a by this reciprocal thus gives a numerical q = a/b 
+    // in Q127 with the following properties: 
+    // 
+    //    1. q < a/b 
+    //    2. q is in the interval [0.5, 2.0) 
+    //    3. the error in q is bounded away from 2^-113 (actually, we have a 
+    //       couple of bits to spare, but this is all we need). 
+ 
+    // We need a 128 x 128 multiply high to compute q, which isn't a basic 
+    // operation in C, so we need to be a little bit fussy. 
+    rep_t quotient, quotientLo; 
+    wideMultiply(aSignificand << 2, reciprocal, &quotient, &quotientLo); 
+ 
+    // Two cases: quotient is in [0.5, 1.0) or quotient is in [1.0, 2.0). 
+    // In either case, we are going to compute a residual of the form 
+    // 
+    //     r = a - q*b 
+    // 
+    // We know from the construction of q that r satisfies: 
+    // 
+    //     0 <= r < ulp(q)*b 
+    // 
+    // if r is greater than 1/2 ulp(q)*b, then q rounds up.  Otherwise, we 
+    // already have the correct result.  The exact halfway case cannot occur. 
+    // We also take this time to right shift quotient if it falls in the [1,2) 
+    // range and adjust the exponent accordingly. 
+    rep_t residual; 
+    rep_t qb; 
+ 
+    if (quotient < (implicitBit << 1)) { 
+        wideMultiply(quotient, bSignificand, &dummy, &qb); 
+        residual = (aSignificand << 113) - qb; 
+        quotientExponent--; 
+    } else { 
+        quotient >>= 1; 
+        wideMultiply(quotient, bSignificand, &dummy, &qb); 
+        residual = (aSignificand << 112) - qb; 
+    } 
+ 
+    const int writtenExponent = quotientExponent + exponentBias; 
+ 
+    if (writtenExponent >= maxExponent) { 
+        // If we have overflowed the exponent, return infinity. 
+        return fromRep(infRep | quotientSign); 
+    } 
+    else if (writtenExponent < 1) { 
+        // Flush denormals to zero.  In the future, it would be nice to add 
+        // code to round them correctly. 
+        return fromRep(quotientSign); 
+    } 
+    else { 
+        const bool round = (residual << 1) >= bSignificand; 
+        // Clear the implicit bit 
+        rep_t absResult = quotient & significandMask; 
+        // Insert the exponent 
+        absResult |= (rep_t)writtenExponent << significandBits; 
+        // Round 
+        absResult += round; 
+        // Insert the sign and return 
+        const long double result = fromRep(absResult | quotientSign); 
+        return result; 
+    } 
+} 
+ 
+#endif