diff --git a/libc/config/linux/api.td b/libc/config/linux/api.td
--- a/libc/config/linux/api.td
+++ b/libc/config/linux/api.td
@@ -155,12 +155,14 @@
    "copysignl",
    "ceil",
    "ceilf",
+   "ceill",
    "cosf",
    "fabs",
    "fabsf",
    "fabsl",
    "floor",
    "floorf",
+   "floorl",
    "frexp",
    "frexpf",
    "frexpl",
@@ -174,6 +176,7 @@
    "exp2f",
    "round",
    "roundf",
+   "roundl",
    "sincosf",
    "sinf",
    "trunc",
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -51,6 +51,7 @@
     libc.src.math.copysignl
     libc.src.math.ceil
     libc.src.math.ceilf
+    libc.src.math.ceill
     libc.src.math.cosf
     libc.src.math.expf
     libc.src.math.exp2f
@@ -59,6 +60,7 @@
     libc.src.math.fabsl
     libc.src.math.floor
     libc.src.math.floorf
+    libc.src.math.floorl
     libc.src.math.frexp
     libc.src.math.frexpf
     libc.src.math.frexpl
@@ -70,6 +72,7 @@
     libc.src.math.modfl
     libc.src.math.round
     libc.src.math.roundf
+    libc.src.math.roundl
     libc.src.math.sincosf
     libc.src.math.sinf
     libc.src.math.trunc
diff --git a/libc/spec/stdc.td b/libc/spec/stdc.td
--- a/libc/spec/stdc.td
+++ b/libc/spec/stdc.td
@@ -195,6 +195,7 @@
 
           FunctionSpec<"ceil", RetValSpec<DoubleType>, [ArgSpec<DoubleType>]>,
           FunctionSpec<"ceilf", RetValSpec<FloatType>, [ArgSpec<FloatType>]>,
+          FunctionSpec<"ceill", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>]>,
 
           FunctionSpec<"fabs", RetValSpec<DoubleType>, [ArgSpec<DoubleType>]>,
           FunctionSpec<"fabsf", RetValSpec<FloatType>, [ArgSpec<FloatType>]>,
@@ -202,6 +203,7 @@
 
           FunctionSpec<"floor", RetValSpec<DoubleType>, [ArgSpec<DoubleType>]>,
           FunctionSpec<"floorf", RetValSpec<FloatType>, [ArgSpec<FloatType>]>,
+          FunctionSpec<"floorl", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>]>,
 
           FunctionSpec<"frexp", RetValSpec<DoubleType>, [ArgSpec<DoubleType>, ArgSpec<IntPtr>]>,
           FunctionSpec<"frexpf", RetValSpec<FloatType>, [ArgSpec<FloatType>, ArgSpec<IntPtr>]>,
@@ -223,6 +225,7 @@
 
           FunctionSpec<"round", RetValSpec<DoubleType>, [ArgSpec<DoubleType>]>,
           FunctionSpec<"roundf", RetValSpec<FloatType>, [ArgSpec<FloatType>]>,
+          FunctionSpec<"roundl", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>]>,
 
           FunctionSpec<"trunc", RetValSpec<DoubleType>, [ArgSpec<DoubleType>]>,
           FunctionSpec<"truncf", RetValSpec<FloatType>, [ArgSpec<FloatType>]>,
diff --git a/libc/src/math/CMakeLists.txt b/libc/src/math/CMakeLists.txt
--- a/libc/src/math/CMakeLists.txt
+++ b/libc/src/math/CMakeLists.txt
@@ -152,6 +152,18 @@
     -O2
 )
 
+add_entrypoint_object(
+  ceill
+  SRCS
+    ceill.cpp
+  HDRS
+    ceill.h
+  DEPENDS
+    libc.utils.FPUtil.fputil
+  COMPILE_OPTIONS
+    -O2
+)
+
 add_entrypoint_object(
   floor
   SRCS
@@ -176,6 +188,18 @@
     -O2
 )
 
+add_entrypoint_object(
+  floorl
+  SRCS
+    floorl.cpp
+  HDRS
+    floorl.h
+  DEPENDS
+    libc.utils.FPUtil.fputil
+  COMPILE_OPTIONS
+    -O2
+)
+
 add_entrypoint_object(
   round
   SRCS
@@ -184,6 +208,8 @@
     round.h
   DEPENDS
     libc.utils.FPUtil.fputil
+  COMPILE_OPTIONS
+    -O2
 )
 
 add_entrypoint_object(
@@ -194,6 +220,20 @@
     roundf.h
   DEPENDS
     libc.utils.FPUtil.fputil
+  COMPILE_OPTIONS
+    -O2
+)
+
+add_entrypoint_object(
+  roundl
+  SRCS
+    roundl.cpp
+  HDRS
+    roundl.h
+  DEPENDS
+    libc.utils.FPUtil.fputil
+  COMPILE_OPTIONS
+    -O2
 )
 
 add_object_library(
diff --git a/libc/src/math/ceill.h b/libc/src/math/ceill.h
new file mode 100644
--- /dev/null
+++ b/libc/src/math/ceill.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for ceill -------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_MATH_CEILL_H
+#define LLVM_LIBC_SRC_MATH_CEILL_H
+
+namespace __llvm_libc {
+
+long double ceill(long double x);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_MATH_CEILL_H
diff --git a/libc/src/math/ceill.cpp b/libc/src/math/ceill.cpp
new file mode 100644
--- /dev/null
+++ b/libc/src/math/ceill.cpp
@@ -0,0 +1,18 @@
+//===-- Implementation of ceill function ----------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/common.h"
+#include "utils/FPUtil/NearestIntegerOperations.h"
+
+namespace __llvm_libc {
+
+long double LLVM_LIBC_ENTRYPOINT(ceill)(long double x) {
+  return fputil::ceil(x);
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/math/floorl.h b/libc/src/math/floorl.h
new file mode 100644
--- /dev/null
+++ b/libc/src/math/floorl.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for floorl ------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_MATH_FLOORL_H
+#define LLVM_LIBC_SRC_MATH_FLOORL_H
+
+namespace __llvm_libc {
+
+long double floorl(long double x);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_MATH_FLOORL_H
diff --git a/libc/src/math/floorl.cpp b/libc/src/math/floorl.cpp
new file mode 100644
--- /dev/null
+++ b/libc/src/math/floorl.cpp
@@ -0,0 +1,18 @@
+//===-- Implementation of floorl function ---------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/common.h"
+#include "utils/FPUtil/NearestIntegerOperations.h"
+
+namespace __llvm_libc {
+
+long double LLVM_LIBC_ENTRYPOINT(floorl)(long double x) {
+  return fputil::floor(x);
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/math/roundl.h b/libc/src/math/roundl.h
new file mode 100644
--- /dev/null
+++ b/libc/src/math/roundl.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for roundl ------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_MATH_ROUNDL_H
+#define LLVM_LIBC_SRC_MATH_ROUNDL_H
+
+namespace __llvm_libc {
+
+long double roundl(long double x);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_MATH_ROUNDL_H
diff --git a/libc/src/math/roundl.cpp b/libc/src/math/roundl.cpp
new file mode 100644
--- /dev/null
+++ b/libc/src/math/roundl.cpp
@@ -0,0 +1,18 @@
+//===-- Implementation of roundl function ---------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/common.h"
+#include "utils/FPUtil/NearestIntegerOperations.h"
+
+namespace __llvm_libc {
+
+long double LLVM_LIBC_ENTRYPOINT(roundl)(long double x) {
+  return fputil::round(x);
+}
+
+} // namespace __llvm_libc
diff --git a/libc/test/src/math/CMakeLists.txt b/libc/test/src/math/CMakeLists.txt
--- a/libc/test/src/math/CMakeLists.txt
+++ b/libc/test/src/math/CMakeLists.txt
@@ -175,6 +175,19 @@
     libc.utils.FPUtil.fputil
 )
 
+add_math_unittest(
+  ceill_test
+  NEED_MPFR
+  SUITE
+    libc_math_unittests
+  SRCS
+    ceill_test.cpp
+  DEPENDS
+    libc.include.math
+    libc.src.math.ceill
+    libc.utils.FPUtil.fputil
+)
+
 add_math_unittest(
   floor_test
   NEED_MPFR
@@ -201,6 +214,19 @@
     libc.utils.FPUtil.fputil
 )
 
+add_math_unittest(
+  floorl_test
+  NEED_MPFR
+  SUITE
+    libc_math_unittests
+  SRCS
+    floorl_test.cpp
+  DEPENDS
+    libc.include.math
+    libc.src.math.floorl
+    libc.utils.FPUtil.fputil
+)
+
 add_math_unittest(
   round_test
   NEED_MPFR
@@ -227,6 +253,19 @@
     libc.utils.FPUtil.fputil
 )
 
+add_math_unittest(
+  roundl_test
+  NEED_MPFR
+  SUITE
+    libc_math_unittests
+  SRCS
+    roundl_test.cpp
+  DEPENDS
+    libc.include.math
+    libc.src.math.roundl
+    libc.utils.FPUtil.fputil
+)
+
 add_math_unittest(
   expf_test
   NEED_MPFR
diff --git a/libc/test/src/math/ceill_test.cpp b/libc/test/src/math/ceill_test.cpp
new file mode 100644
--- /dev/null
+++ b/libc/test/src/math/ceill_test.cpp
@@ -0,0 +1,72 @@
+//===-- Unittests for ceill -----------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "include/math.h"
+#include "src/math/ceill.h"
+#include "utils/FPUtil/FPBits.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+#include "utils/UnitTest/Test.h"
+
+using FPBits = __llvm_libc::fputil::FPBits<long double>;
+
+namespace mpfr = __llvm_libc::testing::mpfr;
+
+// Zero tolerance; As in, exact match with MPFR result.
+static constexpr mpfr::Tolerance tolerance{mpfr::Tolerance::doublePrecision, 0,
+                                           0};
+TEST(CeillTest, SpecialNumbers) {
+  ASSERT_TRUE(FPBits::zero() == __llvm_libc::ceill(FPBits::zero()));
+  ASSERT_TRUE(FPBits::negZero() == __llvm_libc::ceill(FPBits::negZero()));
+
+  ASSERT_TRUE(FPBits::inf() == __llvm_libc::ceill(FPBits::inf()));
+  ASSERT_TRUE(FPBits::negInf() == __llvm_libc::ceill(FPBits::negInf()));
+
+  long double nan = FPBits::buildNaN(1);
+  ASSERT_TRUE(isnan(nan) != 0);
+  ASSERT_TRUE(isnan(__llvm_libc::ceill(nan)) != 0);
+}
+
+TEST(CeillTest, RoundedNumbers) {
+  ASSERT_TRUE(FPBits(1.0l) == __llvm_libc::ceill(1.0l));
+  ASSERT_TRUE(FPBits(-1.0l) == __llvm_libc::ceill(-1.0l));
+  ASSERT_TRUE(FPBits(10.0l) == __llvm_libc::ceill(10.0l));
+  ASSERT_TRUE(FPBits(-10.0l) == __llvm_libc::ceill(-10.0l));
+  ASSERT_TRUE(FPBits(1234.0l) == __llvm_libc::ceill(1234.0l));
+  ASSERT_TRUE(FPBits(-1234.0l) == __llvm_libc::ceill(-1234.0l));
+}
+
+TEST(CeillTest, Fractions) {
+  ASSERT_TRUE(FPBits(2.0l) == __llvm_libc::ceill(1.3l));
+  ASSERT_TRUE(FPBits(-1.0l) == __llvm_libc::ceill(-1.3l));
+  ASSERT_TRUE(FPBits(2.0l) == __llvm_libc::ceill(1.5l));
+  ASSERT_TRUE(FPBits(-1.0l) == __llvm_libc::ceill(-1.5l));
+  ASSERT_TRUE(FPBits(2.0l) == __llvm_libc::ceill(1.75l));
+  ASSERT_TRUE(FPBits(-1.0l) == __llvm_libc::ceill(-1.75l));
+  ASSERT_TRUE(FPBits(11.0l) == __llvm_libc::ceill(10.32l));
+  ASSERT_TRUE(FPBits(-10.0l) == __llvm_libc::ceill(-10.32l));
+  ASSERT_TRUE(FPBits(11.0l) == __llvm_libc::ceill(10.65l));
+  ASSERT_TRUE(FPBits(-10.0l) == __llvm_libc::ceill(-10.65l));
+  ASSERT_TRUE(FPBits(1235.0l) == __llvm_libc::ceill(1234.18l));
+  ASSERT_TRUE(FPBits(-1234.0l) == __llvm_libc::ceill(-1234.18l));
+  ASSERT_TRUE(FPBits(1235.0l) == __llvm_libc::ceill(1234.96l));
+  ASSERT_TRUE(FPBits(-1234.0l) == __llvm_libc::ceill(-1234.96l));
+}
+
+TEST(CeillTest, InLongDoubleRange) {
+  using UIntType = FPBits::UIntType;
+  constexpr UIntType count = 10000000;
+  constexpr UIntType step = UIntType(-1) / count;
+  for (UIntType i = 0, v = 0; i <= count; ++i, v += step) {
+    long double x = FPBits(v);
+    if (isnan(x) || isinf(x))
+      continue;
+
+    ASSERT_MPFR_MATCH(mpfr::Operation::Ceil, x, __llvm_libc::ceill(x),
+                      tolerance);
+  }
+}
diff --git a/libc/test/src/math/floorl_test.cpp b/libc/test/src/math/floorl_test.cpp
new file mode 100644
--- /dev/null
+++ b/libc/test/src/math/floorl_test.cpp
@@ -0,0 +1,72 @@
+//===-- Unittests for floorl ----------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "include/math.h"
+#include "src/math/floorl.h"
+#include "utils/FPUtil/FPBits.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+#include "utils/UnitTest/Test.h"
+
+using FPBits = __llvm_libc::fputil::FPBits<long double>;
+
+namespace mpfr = __llvm_libc::testing::mpfr;
+
+// Zero tolerance; As in, exact match with MPFR result.
+static constexpr mpfr::Tolerance tolerance{mpfr::Tolerance::doublePrecision, 0,
+                                           0};
+TEST(FloorlTest, SpecialNumbers) {
+  ASSERT_TRUE(FPBits::zero() == __llvm_libc::floorl(FPBits::zero()));
+  ASSERT_TRUE(FPBits::negZero() == __llvm_libc::floorl(FPBits::negZero()));
+
+  ASSERT_TRUE(FPBits::inf() == __llvm_libc::floorl(FPBits::inf()));
+  ASSERT_TRUE(FPBits::negInf() == __llvm_libc::floorl(FPBits::negInf()));
+
+  long double nan = FPBits::buildNaN(1);
+  ASSERT_TRUE(isnan(nan) != 0);
+  ASSERT_TRUE(isnan(__llvm_libc::floorl(nan)) != 0);
+}
+
+TEST(FloorlTest, RoundedNumbers) {
+  ASSERT_TRUE(FPBits(1.0l) == __llvm_libc::floorl(1.0l));
+  ASSERT_TRUE(FPBits(-1.0l) == __llvm_libc::floorl(-1.0l));
+  ASSERT_TRUE(FPBits(10.0l) == __llvm_libc::floorl(10.0l));
+  ASSERT_TRUE(FPBits(-10.0l) == __llvm_libc::floorl(-10.0l));
+  ASSERT_TRUE(FPBits(1234.0l) == __llvm_libc::floorl(1234.0l));
+  ASSERT_TRUE(FPBits(-1234.0l) == __llvm_libc::floorl(-1234.0l));
+}
+
+TEST(FloorlTest, Fractions) {
+  ASSERT_TRUE(FPBits(1.0l) == __llvm_libc::floorl(1.3l));
+  ASSERT_TRUE(FPBits(-2.0l) == __llvm_libc::floorl(-1.3l));
+  ASSERT_TRUE(FPBits(1.0l) == __llvm_libc::floorl(1.5l));
+  ASSERT_TRUE(FPBits(-2.0l) == __llvm_libc::floorl(-1.5l));
+  ASSERT_TRUE(FPBits(1.0l) == __llvm_libc::floorl(1.75l));
+  ASSERT_TRUE(FPBits(-2.0l) == __llvm_libc::floorl(-1.75l));
+  ASSERT_TRUE(FPBits(10.0l) == __llvm_libc::floorl(10.32l));
+  ASSERT_TRUE(FPBits(-11.0l) == __llvm_libc::floorl(-10.32l));
+  ASSERT_TRUE(FPBits(10.0l) == __llvm_libc::floorl(10.65l));
+  ASSERT_TRUE(FPBits(-11.0l) == __llvm_libc::floorl(-10.65l));
+  ASSERT_TRUE(FPBits(1234.0l) == __llvm_libc::floorl(1234.18l));
+  ASSERT_TRUE(FPBits(-1235.0l) == __llvm_libc::floorl(-1234.18l));
+  ASSERT_TRUE(FPBits(1234.0l) == __llvm_libc::floorl(1234.96l));
+  ASSERT_TRUE(FPBits(-1235.0l) == __llvm_libc::floorl(-1234.96l));
+}
+
+TEST(FloorlTest, InLongDoubleRange) {
+  using UIntType = FPBits::UIntType;
+  constexpr UIntType count = 10000000;
+  constexpr UIntType step = UIntType(-1) / count;
+  for (UIntType i = 0, v = 0; i <= count; ++i, v += step) {
+    long double x = FPBits(v);
+    if (isnan(x) || isinf(x))
+      continue;
+
+    ASSERT_MPFR_MATCH(mpfr::Operation::Floor, x, __llvm_libc::floorl(x),
+                      tolerance);
+  }
+}
diff --git a/libc/test/src/math/roundl_test.cpp b/libc/test/src/math/roundl_test.cpp
new file mode 100644
--- /dev/null
+++ b/libc/test/src/math/roundl_test.cpp
@@ -0,0 +1,72 @@
+//===-- Unittests for roundl ----------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "include/math.h"
+#include "src/math/roundl.h"
+#include "utils/FPUtil/FPBits.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+#include "utils/UnitTest/Test.h"
+
+using FPBits = __llvm_libc::fputil::FPBits<long double>;
+
+namespace mpfr = __llvm_libc::testing::mpfr;
+
+// Zero tolerance; As in, exact match with MPFR result.
+static constexpr mpfr::Tolerance tolerance{mpfr::Tolerance::floatPrecision, 0,
+                                           0};
+TEST(RoundlTest, SpecialNumbers) {
+  ASSERT_TRUE(FPBits::zero() == __llvm_libc::roundl(FPBits::zero()));
+  ASSERT_TRUE(FPBits::negZero() == __llvm_libc::roundl(FPBits::negZero()));
+
+  ASSERT_TRUE(FPBits::inf() == __llvm_libc::roundl(FPBits::inf()));
+  ASSERT_TRUE(FPBits::negInf() == __llvm_libc::roundl(FPBits::negInf()));
+
+  long double nan = FPBits::buildNaN(1);
+  ASSERT_TRUE(isnan(nan) != 0);
+  ASSERT_TRUE(isnan(__llvm_libc::roundl(nan)) != 0);
+}
+
+TEST(RoundlTest, RoundedNumbers) {
+  ASSERT_TRUE(FPBits(1.0l) == __llvm_libc::roundl(1.0l));
+  ASSERT_TRUE(FPBits(-1.0l) == __llvm_libc::roundl(-1.0l));
+  ASSERT_TRUE(FPBits(10.0l) == __llvm_libc::roundl(10.0l));
+  ASSERT_TRUE(FPBits(-10.0l) == __llvm_libc::roundl(-10.0l));
+  ASSERT_TRUE(FPBits(1234.0l) == __llvm_libc::roundl(1234.0l));
+  ASSERT_TRUE(FPBits(-1234.0l) == __llvm_libc::roundl(-1234.0l));
+}
+
+TEST(RoundlTest, Fractions) {
+  ASSERT_TRUE(FPBits(1.0l) == __llvm_libc::roundl(1.3l));
+  ASSERT_TRUE(FPBits(-1.0l) == __llvm_libc::roundl(-1.3l));
+  ASSERT_TRUE(FPBits(2.0l) == __llvm_libc::roundl(1.5l));
+  ASSERT_TRUE(FPBits(-2.0l) == __llvm_libc::roundl(-1.5l));
+  ASSERT_TRUE(FPBits(2.0l) == __llvm_libc::roundl(1.75l));
+  ASSERT_TRUE(FPBits(-2.0l) == __llvm_libc::roundl(-1.75l));
+  ASSERT_TRUE(FPBits(10.0l) == __llvm_libc::roundl(10.32l));
+  ASSERT_TRUE(FPBits(-10.0l) == __llvm_libc::roundl(-10.32l));
+  ASSERT_TRUE(FPBits(11.0l) == __llvm_libc::roundl(10.65l));
+  ASSERT_TRUE(FPBits(-11.0l) == __llvm_libc::roundl(-10.65l));
+  ASSERT_TRUE(FPBits(1234.0l) == __llvm_libc::roundl(1234.38l));
+  ASSERT_TRUE(FPBits(-1234.0l) == __llvm_libc::roundl(-1234.38l));
+  ASSERT_TRUE(FPBits(1235.0l) == __llvm_libc::roundl(1234.96l));
+  ASSERT_TRUE(FPBits(-1235.0l) == __llvm_libc::roundl(-1234.96l));
+}
+
+TEST(RoundlTest, InLongDoubleRange) {
+  using UIntType = FPBits::UIntType;
+  constexpr UIntType count = 10000000;
+  constexpr UIntType step = UIntType(-1) / count;
+  for (UIntType i = 0, v = 0; i <= count; ++i, v += step) {
+    long double x = FPBits(v);
+    if (isnan(x) || isinf(x))
+      continue;
+
+    ASSERT_MPFR_MATCH(mpfr::Operation::Round, x, __llvm_libc::roundl(x),
+                      tolerance);
+  }
+}
diff --git a/libc/utils/FPUtil/NearestIntegerOperations.h b/libc/utils/FPUtil/NearestIntegerOperations.h
--- a/libc/utils/FPUtil/NearestIntegerOperations.h
+++ b/libc/utils/FPUtil/NearestIntegerOperations.h
@@ -9,10 +9,7 @@
 #ifndef LLVM_LIBC_UTILS_FPUTIL_NEAREST_INTEGER_OPERATIONS_H
 #define LLVM_LIBC_UTILS_FPUTIL_NEAREST_INTEGER_OPERATIONS_H
 
-#include "ClassificationFunctions.h"
 #include "FPBits.h"
-#include "FloatOperations.h"
-#include "FloatProperties.h"
 
 #include "utils/CPP/TypeTraits.h"
 
@@ -54,21 +51,18 @@
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
 static inline T ceil(T x) {
-  using Properties = FloatProperties<T>;
-  using BitsType = typename FloatProperties<T>::BitsType;
-
-  BitsType bits = valueAsBits(x);
+  FPBits<T> bits(x);
 
   // If x is infinity NaN or zero, return it.
-  if (bitsAreInfOrNaN(bits) || bitsAreZero(bits))
+  if (bits.isInfOrNaN() || bits.isZero())
     return x;
 
-  bool isNeg = bits & Properties::signMask;
-  int exponent = getExponentFromBits(bits);
+  bool isNeg = bits.sign;
+  int exponent = bits.getExponent();
 
   // If the exponent is greater than the most negative mantissa
   // exponent, then x is already an integer.
-  if (exponent >= static_cast<int>(Properties::mantissaWidth))
+  if (exponent >= static_cast<int>(MantissaWidth<T>::value))
     return x;
 
   if (exponent <= -1) {
@@ -78,14 +72,14 @@
       return T(1.0);
   }
 
-  uint32_t trimSize = Properties::mantissaWidth - exponent;
+  uint32_t trimSize = MantissaWidth<T>::value - exponent;
+  bits.mantissa = (bits.mantissa >> trimSize) << trimSize;
+  T truncValue = T(bits);
+
   // If x is already an integer, return it.
-  if ((bits << (Properties::bitWidth - trimSize)) == 0)
+  if (truncValue == x)
     return x;
 
-  BitsType truncBits = (bits >> trimSize) << trimSize;
-  T truncValue = valueFromBits(truncBits);
-
   // If x is negative, the ceil operation is equivalent to the trunc operation.
   if (isNeg)
     return truncValue;
@@ -96,8 +90,8 @@
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
 static inline T floor(T x) {
-  auto bits = valueAsBits(x);
-  if (FloatProperties<T>::signMask & bits) {
+  FPBits<T> bits(x);
+  if (bits.sign) {
     return -ceil(-x);
   } else {
     return trunc(x);
@@ -107,21 +101,19 @@
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
 static inline T round(T x) {
-  using Properties = FloatProperties<T>;
-  using BitsType = typename FloatProperties<T>::BitsType;
-
-  BitsType bits = valueAsBits(x);
+  using UIntType = typename FPBits<T>::UIntType;
+  FPBits<T> bits(x);
 
-  // If x is infinity, NaN or zero, return it.
-  if (bitsAreInfOrNaN(bits) || bitsAreZero(bits))
+  // If x is infinity NaN or zero, return it.
+  if (bits.isInfOrNaN() || bits.isZero())
     return x;
 
-  bool isNeg = bits & Properties::signMask;
-  int exponent = getExponentFromBits(bits);
+  bool isNeg = bits.sign;
+  int exponent = bits.getExponent();
 
   // If the exponent is greater than the most negative mantissa
   // exponent, then x is already an integer.
-  if (exponent >= static_cast<int>(Properties::mantissaWidth))
+  if (exponent >= static_cast<int>(MantissaWidth<T>::value))
     return x;
 
   if (exponent == -1) {
@@ -140,24 +132,22 @@
       return T(0.0);
   }
 
-  uint32_t trimSize = Properties::mantissaWidth - exponent;
+  uint32_t trimSize = MantissaWidth<T>::value - exponent;
+  bool halfBitSet = bits.mantissa & (UIntType(1) << (trimSize - 1));
+  bits.mantissa = (bits.mantissa >> trimSize) << trimSize;
+  T truncValue = T(bits);
+
   // If x is already an integer, return it.
-  if ((bits << (Properties::bitWidth - trimSize)) == 0)
+  if (truncValue == x)
     return x;
 
-  BitsType truncBits = (bits >> trimSize) << trimSize;
-  T truncValue = valueFromBits(truncBits);
-
-  if ((bits & (BitsType(1) << (trimSize - 1))) == 0) {
+  if (!halfBitSet) {
     // Franctional part is less than 0.5 so round value is the
     // same as the trunc value.
     return truncValue;
+  } else {
+    return isNeg ? truncValue - T(1.0) : truncValue + T(1.0);
   }
-
-  if (isNeg)
-    return truncValue - T(1.0);
-  else
-    return truncValue + T(1.0);
 }
 
 } // namespace fputil