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diff --git a/contrib/llvm-project/compiler-rt/lib/builtins/fp_add_impl.inc b/contrib/llvm-project/compiler-rt/lib/builtins/fp_add_impl.inc
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index 000000000000..d20599921e7d
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+++ b/contrib/llvm-project/compiler-rt/lib/builtins/fp_add_impl.inc
@@ -0,0 +1,172 @@
+//===----- lib/fp_add_impl.inc - floaing point addition -----------*- C -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements soft-float addition with the IEEE-754 default rounding
+// (to nearest, ties to even).
+//
+//===----------------------------------------------------------------------===//
+
+#include "fp_lib.h"
+#include "fp_mode.h"
+
+static __inline fp_t __addXf3__(fp_t a, fp_t b) {
+  rep_t aRep = toRep(a);
+  rep_t bRep = toRep(b);
+  const rep_t aAbs = aRep & absMask;
+  const rep_t bAbs = bRep & absMask;
+
+  // Detect if a or b is zero, infinity, or NaN.
+  if (aAbs - REP_C(1) >= infRep - REP_C(1) ||
+      bAbs - REP_C(1) >= infRep - REP_C(1)) {
+    // 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 = qNaN
+      if ((toRep(a) ^ toRep(b)) == signBit)
+        return fromRep(qnanRep);
+      // +/-infinity + anything remaining = +/- infinity
+      else
+        return a;
+    }
+
+    // anything remaining + +/-infinity = +/-infinity
+    if (bAbs == infRep)
+      return b;
+
+    // zero + anything = anything
+    if (!aAbs) {
+      // We need to get the sign right for zero + zero.
+      if (!bAbs)
+        return fromRep(toRep(a) & toRep(b));
+      else
+        return b;
+    }
+
+    // anything + zero = anything
+    if (!bAbs)
+      return a;
+  }
+
+  // Swap a and b if necessary so that a has the larger absolute value.
+  if (bAbs > aAbs) {
+    const rep_t temp = aRep;
+    aRep = bRep;
+    bRep = temp;
+  }
+
+  // Extract the exponent and significand from the (possibly swapped) a and b.
+  int aExponent = aRep >> significandBits & maxExponent;
+  int bExponent = bRep >> significandBits & maxExponent;
+  rep_t aSignificand = aRep & significandMask;
+  rep_t bSignificand = bRep & significandMask;
+
+  // Normalize any denormals, and adjust the exponent accordingly.
+  if (aExponent == 0)
+    aExponent = normalize(&aSignificand);
+  if (bExponent == 0)
+    bExponent = normalize(&bSignificand);
+
+  // The sign of the result is the sign of the larger operand, a.  If they
+  // have opposite signs, we are performing a subtraction.  Otherwise, we
+  // perform addition.
+  const rep_t resultSign = aRep & signBit;
+  const bool subtraction = (aRep ^ bRep) & signBit;
+
+  // Shift the significands to give us round, guard and sticky, and set 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 = (aSignificand | implicitBit) << 3;
+  bSignificand = (bSignificand | implicitBit) << 3;
+
+  // Shift the significand of b by the difference in exponents, with a sticky
+  // bottom bit to get rounding correct.
+  const unsigned int align = (unsigned int)(aExponent - bExponent);
+  if (align) {
+    if (align < typeWidth) {
+      const bool sticky = (bSignificand << (typeWidth - align)) != 0;
+      bSignificand = bSignificand >> align | sticky;
+    } else {
+      bSignificand = 1; // Set the sticky bit.  b is known to be non-zero.
+    }
+  }
+  if (subtraction) {
+    aSignificand -= bSignificand;
+    // If a == -b, return +zero.
+    if (aSignificand == 0)
+      return fromRep(0);
+
+    // If partial cancellation occured, we need to left-shift the result
+    // and adjust the exponent.
+    if (aSignificand < implicitBit << 3) {
+      const int shift = rep_clz(aSignificand) - rep_clz(implicitBit << 3);
+      aSignificand <<= shift;
+      aExponent -= shift;
+    }
+  } else /* addition */ {
+    aSignificand += bSignificand;
+
+    // If the addition carried up, we need to right-shift the result and
+    // adjust the exponent.
+    if (aSignificand & implicitBit << 4) {
+      const bool sticky = aSignificand & 1;
+      aSignificand = aSignificand >> 1 | sticky;
+      aExponent += 1;
+    }
+  }
+
+  // If we have overflowed the type, return +/- infinity.
+  if (aExponent >= maxExponent)
+    return fromRep(infRep | resultSign);
+
+  if (aExponent <= 0) {
+    // The result is denormal before rounding.  The exponent is zero and we
+    // need to shift the significand.
+    const int shift = 1 - aExponent;
+    const bool sticky = (aSignificand << (typeWidth - shift)) != 0;
+    aSignificand = aSignificand >> shift | sticky;
+    aExponent = 0;
+  }
+
+  // Low three bits are round, guard, and sticky.
+  const int roundGuardSticky = aSignificand & 0x7;
+
+  // Shift the significand into place, and mask off the implicit bit.
+  rep_t result = aSignificand >> 3 & significandMask;
+
+  // Insert the exponent and sign.
+  result |= (rep_t)aExponent << significandBits;
+  result |= resultSign;
+
+  // Perform the final rounding.  The result may overflow to infinity, but
+  // that is the correct result in that case.
+  switch (__fe_getround()) {
+  case CRT_FE_TONEAREST:
+    if (roundGuardSticky > 0x4)
+      result++;
+    if (roundGuardSticky == 0x4)
+      result += result & 1;
+    break;
+  case CRT_FE_DOWNWARD:
+    if (resultSign && roundGuardSticky) result++;
+    break;
+  case CRT_FE_UPWARD:
+    if (!resultSign && roundGuardSticky) result++;
+    break;
+  case CRT_FE_TOWARDZERO:
+    break;
+  }
+  if (roundGuardSticky)
+    __fe_raise_inexact();
+  return fromRep(result);
+}