diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 000000000..9f67cfc31
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,167 @@
+# How to contribute
+
+## compiler-builtins
+
+1. From the [pending list](compiler-builtins/README.md#progress), pick one or
+   more intrinsics.
+2. Port the version from [`compiler-rt`] and, if applicable, their
+   [tests][rt-tests]. Note that this crate has generic implementations for a lot
+   of routines, which may be usable without porting the entire implementation.
+3. Add a test to `builtins-test`, comparing the behavior of the ported
+   intrinsic(s) with their implementation on the testing host.
+4. Add the intrinsic to `builtins-test-intrinsics/src/main.rs` to verify it can
+   be linked on all targets.
+5. Send a Pull Request (PR) :tada:.
+
+[`compiler-rt`]: https://github.com/llvm/llvm-project/tree/b6820c35c59a4da3e59c11f657093ffbd79ae1db/compiler-rt/lib/builtins
+[rt-tests]: https://github.com/llvm/llvm-project/tree/b6820c35c59a4da3e59c11f657093ffbd79ae1db/compiler-rt/test/builtins
+
+## Porting Reminders
+
+1. [Rust][prec-rust] and [C][prec-c] have slightly different operator
+   precedence. C evaluates comparisons (`== !=`) before bitwise operations
+   (`& | ^`), while Rust evaluates the other way.
+2. C assumes wrapping operations everywhere. Rust panics on overflow when in
+   debug mode. Consider using the [Wrapping][wrap-ty] type or the explicit
+   [wrapping_*][wrap-fn] functions where applicable.
+3. Note [C implicit casts][casts], especially integer promotion. Rust is much
+   more explicit about casting, so be sure that any cast which affects the
+   output is ported to the Rust implementation.
+4. Rust has [many functions][i32] for integer or floating point manipulation in
+   the standard library. Consider using one of these functions rather than
+   porting a new one.
+
+[prec-rust]: https://doc.rust-lang.org/reference/expressions.html#expression-precedence
+[prec-c]: http://en.cppreference.com/w/c/language/operator_precedence
+[wrap-ty]: https://doc.rust-lang.org/core/num/struct.Wrapping.html
+[wrap-fn]: https://doc.rust-lang.org/std/primitive.i32.html#method.wrapping_add
+[casts]: http://en.cppreference.com/w/cpp/language/implicit_conversion
+[i32]: https://doc.rust-lang.org/std/primitive.i32.html
+
+## Tips and tricks
+
+- _IMPORTANT_ The code in this crate will end up being used in the `core` crate
+  so it can **not** have any external dependencies (other than a subset of
+  `core` itself).
+- Only use relative imports within the `math` directory / module, e.g.
+  `use self::fabs::fabs` or `use super::k_cos`. Absolute imports from core are
+  OK, e.g. `use core::u64`.
+- To reinterpret a float as an integer use the `to_bits` method. The MUSL code
+  uses the `GET_FLOAT_WORD` macro, or a union, to do this operation.
+- To reinterpret an integer as a float use the `f32::from_bits` constructor. The
+  MUSL code uses the `SET_FLOAT_WORD` macro, or a union, to do this operation.
+- You may use other methods from core like `f64::is_nan`, etc. as appropriate.
+- Rust does not have hex float literals. This crate provides two `hf16!`,
+  `hf32!`, `hf64!`, and `hf128!` which convert string literals to floats at
+  compile time.
+
+  ```rust
+  assert_eq!(hf32!("0x1.ffep+8").to_bits(), 0x43fff000);
+  assert_eq!(hf64!("0x1.ffep+8").to_bits(), 0x407ffe0000000000);
+  ```
+
+- Rust code panics on arithmetic overflows when not optimized. You may need to
+  use the [`Wrapping`] newtype to avoid this problem, or individual methods like
+  [`wrapping_add`].
+
+[`Wrapping`]: https://doc.rust-lang.org/std/num/struct.Wrapping.html
+[`wrapping_add`]: https://doc.rust-lang.org/std/primitive.u32.html#method.wrapping_add
+
+## Testing
+
+Testing for these crates can be somewhat complex, so feel free to rely on CI.
+
+The easiest way replicate CI testing is using Docker. This can be done by
+running `./ci/run-docker.sh [target]`. If no target is specified, all targets
+will be run.
+
+Tests can also be run without Docker:
+
+```sh
+# Run basic tests
+#
+# --no-default-features always needs to be passed, an unfortunate limitation
+# since the `#![compiler_builtins]` feature is enabled by default.
+cargo test --workspace --no-default-features
+
+# Test with all interesting features
+cargo test --workspace --no-default-features \
+    --features arch,unstable-float,unstable-intrinsics,mem
+
+# Run with more detailed tests for libm
+cargo test --workspace --no-default-features \
+    --features arch,unstable-float,unstable-intrinsics,mem \
+    --features build-mpfr,build-musl \
+    --profile release-checked
+```
+
+The multiprecision tests use the [`rug`] crate for bindings to MPFR. MPFR can be
+difficult to build on non-Unix systems, refer to [`gmp_mpfr_sys`] for help.
+
+`build-musl` does not build with MSVC, Wasm, or Thumb.
+
+[`rug`]: https://docs.rs/rug/latest/rug/
+[`gmp_mpfr_sys`]: https://docs.rs/gmp-mpfr-sys/1.6.4/gmp_mpfr_sys/
+
+In order to run all tests, some dependencies may be required:
+
+```sh
+# Allow testing compiler-builtins
+./ci/download-compiler-rt.sh
+
+# Optional, initialize musl for `--features build-musl`
+git submodule init
+git submodule update
+
+# `--release` ables more test cases
+cargo test --release
+```
+
+### Extensive tests
+
+Libm also has tests that are exhaustive (for single-argument `f32` and 1- or 2-
+argument `f16`) or extensive (for all other float and argument combinations).
+These take quite a long time to run, but are launched in CI when relevant files
+are changed.
+
+Exhaustive tests can be selected by passing an environment variable:
+
+```sh
+LIBM_EXTENSIVE_TESTS=sqrt,sqrtf cargo test --features build-mpfr \
+    --test z_extensive \
+    --profile release-checked
+
+# Run all tests for one type
+LIBM_EXTENSIVE_TESTS=all_f16 cargo test ...
+
+# Ensure `f64` tests can run exhaustively. Estimated completion test for a
+# single test is 57306 years on my machine so this may be worth skipping.
+LIBM_EXTENSIVE_TESTS=all LIBM_EXTENSIVE_ITERATIONS=18446744073709551615 cargo test ...
+```
+
+## Benchmarking
+
+Regular walltime benchmarks can be run with `cargo bench`:
+
+```sh
+cargo bench --no-default-features \
+    --features arch,unstable-float,unstable-intrinsics,mem \
+    --features benchmarking-reports
+```
+
+There are also benchmarks that check instruction count behind the `icount`
+feature. These require [`iai-callgrind-runner`] (via Cargo) and [Valgrind]
+to be installed, which means these only run on limited platforms.
+
+Instruction count benchmarks are run as part of CI to flag performance
+regresions.
+
+```sh
+cargo bench --no-default-features \
+    --features arch,unstable-float,unstable-intrinsics,mem \
+    --features icount \
+    --bench icount --bench mem_icount
+```
+
+[`iai-callgrind-runner`]: https://crates.io/crates/iai-callgrind-runner
+[Valgrind]: https://valgrind.org/
diff --git a/LICENSE.txt b/LICENSE.txt
index 367e3538d..00ae6140b 100644
--- a/LICENSE.txt
+++ b/LICENSE.txt
@@ -1,10 +1,14 @@
-compiler-builtins as a whole is available for use under both the MIT license
+The compiler-builtins crate is available for use under both the MIT license
 and the Apache-2.0 license with the LLVM exception (MIT AND Apache-2.0 WITH
 LLVM-exception).
 
-As a contributor, you agree that your code can be used under either the MIT
-license, or the Apache-2.0 license, or the Apache-2.0 license with the LLVM
-exception.
+The libm crate is available for use under the MIT license.
+
+As a contributor, you agree that your code may be used under any of the
+following: the MIT license, the Apache-2.0 license, or the Apache-2.0 license
+with the LLVM exception. In other words, original (non-derivative) work is
+licensed under MIT OR Apache-2.0 OR Apache-2.0 WITH LLVM-exception. This is
+the default license for all other source in this repository.
 
 Text of the relevant licenses is provided below:
 
@@ -263,8 +267,9 @@ license:
 * Work derived from compiler-rt after 2019-01-19 is usable under the
   Apache-2.0 license with the LLVM exception.
 
-* The bundled `math` module is from rust-lang/libm, usable under the MIT
-  license. See https://github.com/rust-lang/libm for details.
+* The bundled `math` module is from the libm crate, usable under the MIT
+  license. For further details and copyrights, see see libm/LICENSE.txt at
+  https://github.com/rust-lang/compiler-builtins.
 
 Additionally, some source files may contain comments with specific copyrights
 or licenses.
diff --git a/README.md b/README.md
index e5350d58c..3130ff7b7 100644
--- a/README.md
+++ b/README.md
@@ -1,476 +1,27 @@
-# `compiler-builtins`
+# `compiler-builtins` and `libm`
 
-This crate provides external symbols that the compiler expects to be available when
-building Rust projects, typically software routines for basic operations that do not
-have hardware support. It is largely a port of LLVM's [`compiler-rt`].
+This repository contains two main crates:
 
-It is distributed as part of Rust's sysroot.
+* `compiler-builtins`: symbols that the compiler expects to be available at
+  link time
+* `libm`: a Rust implementation of C math libraries, used to provide
+  implementations in `ocre`.
 
-[`compiler-rt`]: https://github.com/llvm/llvm-project/tree/1b1dc505057322f4fa1110ef4f53c44347f52986/compiler-rt
+More details are at [compiler-builtins/README.md](compiler-builtins/README.md)
+and [libm/README.md](libm/README.md).
 
-## Contributing
-
-1. Pick one or more intrinsics from the [pending list](#progress).
-2. Fork this repository.
-3. Port the intrinsic(s) and their corresponding [unit tests][1] from their
-   [C implementation][2] to Rust.
-4. Add a test to compare the behavior of the ported intrinsic(s) with their
-   implementation on the testing host.
-5. Add the intrinsic to `builtins-test-intrinsics/src/main.rs` to verify it
-   can be linked on all targets.
-6. Send a Pull Request (PR).
-7. Once the PR passes our extensive testing infrastructure, we'll merge it!
-8. Celebrate :tada:
-
-[1]: https://github.com/rust-lang/llvm-project/tree/9e3de9490ff580cd484fbfa2908292b4838d56e7/compiler-rt/test/builtins/Unit
-[2]: https://github.com/rust-lang/llvm-project/tree/9e3de9490ff580cd484fbfa2908292b4838d56e7/compiler-rt/lib/builtins
-[3]: https://github.com/rust-lang/compiler-builtins/actions
-
-### Porting Reminders
-
-1. [Rust][5a] and [C][5b] have slightly different operator precedence. C evaluates comparisons (`== !=`) before bitwise operations (`& | ^`), while Rust evaluates the other way.
-2. C assumes wrapping operations everywhere. Rust panics on overflow when in debug mode. Consider using the [Wrapping][6] type or the explicit [wrapping_*][7] functions where applicable.
-3. Note [C implicit casts][8], especially integer promotion. Rust is much more explicit about casting, so be sure that any cast which affects the output is ported to the Rust implementation.
-4. Rust has [many functions][9] for integer or floating point manipulation in the standard library. Consider using one of these functions rather than porting a new one.
-
-[5a]: https://doc.rust-lang.org/reference/expressions.html#expression-precedence
-[5b]: http://en.cppreference.com/w/c/language/operator_precedence
-[6]: https://doc.rust-lang.org/core/num/struct.Wrapping.html
-[7]: https://doc.rust-lang.org/std/primitive.i32.html#method.wrapping_add
-[8]: http://en.cppreference.com/w/cpp/language/implicit_conversion
-[9]: https://doc.rust-lang.org/std/primitive.i32.html
-
-## Testing
-
-The easiest way to test locally is using Docker. This can be done by running
-`./ci/run-docker.sh [target]`. If no target is specified, all targets will be
-run.
-
-In order to run the full test suite, you will also need the C compiler runtime
-to test against, located in a directory called `compiler-rt`. This can be
-obtained with the following:
-
-```sh
-curl -L -o rustc-llvm-20.1.tar.gz https://github.com/rust-lang/llvm-project/archive/rustc/20.1-2025-02-13.tar.gz
-tar xzf rustc-llvm-20.1.tar.gz --strip-components 1 llvm-project-rustc-20.1-2025-02-13/compiler-rt
-```
-
-Local targets may also be tested with `./ci/run.sh [target]`.
-
-Note that testing may not work on all hosts, in which cases it is acceptable to
-rely on CI.
-
-## Progress
-
-- [x] aarch64/chkstk.S
-- [x] adddf3.c
-- [x] addsf3.c
-- [x] arm/addsf3.S
-- [x] arm/aeabi_dcmp.S
-- [x] arm/aeabi_fcmp.S
-- [x] arm/aeabi_idivmod.S
-- [x] arm/aeabi_ldivmod.S
-- [x] arm/aeabi_memcpy.S
-- [x] arm/aeabi_memmove.S
-- [x] arm/aeabi_memset.S
-- [x] arm/aeabi_uidivmod.S
-- [x] arm/aeabi_uldivmod.S
-- [ ] arm/chkstk.S
-- [ ] arm/divmodsi4.S (generic version is done)
-- [ ] arm/divsi3.S (generic version is done)
-- [ ] arm/modsi3.S (generic version is done)
-- [x] arm/softfloat-alias.list
-- [ ] arm/udivmodsi4.S (generic version is done)
-- [ ] arm/udivsi3.S (generic version is done)
-- [ ] arm/umodsi3.S (generic version is done)
-- [x] ashldi3.c
-- [x] ashrdi3.c
-- [ ] avr/divmodhi4.S
-- [ ] avr/divmodqi4.S
-- [ ] avr/mulhi3.S
-- [ ] avr/mulqi3.S
-- [ ] avr/udivmodhi4.S
-- [ ] avr/udivmodqi4.S
-- [x] bswapdi2.c
-- [x] bswapsi2.c
-- [x] bswapti2.c
-- [x] clzdi2.c
-- [x] clzsi2.c
-- [x] clzti2.c
-- [x] comparedf2.c
-- [x] comparesf2.c
-- [x] ctzdi2.c
-- [x] ctzsi2.c
-- [x] ctzti2.c
-- [x] divdf3.c
-- [x] divdi3.c
-- [x] divmoddi4.c
-- [x] divmodsi4.c
-- [x] divmodti4.c
-- [x] divsf3.c
-- [x] divsi3.c
-- [x] extendsfdf2.c
-- [x] fixdfdi.c
-- [x] fixdfsi.c
-- [x] fixsfdi.c
-- [x] fixsfsi.c
-- [x] fixunsdfdi.c
-- [x] fixunsdfsi.c
-- [x] fixunssfdi.c
-- [x] fixunssfsi.c
-- [x] floatdidf.c
-- [x] floatdisf.c
-- [x] floatsidf.c
-- [x] floatsisf.c
-- [x] floatundidf.c
-- [x] floatundisf.c
-- [x] floatunsidf.c
-- [x] floatunsisf.c
-- [ ] i386/ashldi3.S
-- [ ] i386/ashrdi3.S
-- [x] i386/chkstk.S
-- [ ] i386/divdi3.S
-- [ ] i386/lshrdi3.S
-- [ ] i386/moddi3.S
-- [ ] i386/muldi3.S
-- [ ] i386/udivdi3.S
-- [ ] i386/umoddi3.S
-- [x] lshrdi3.c
-- [x] moddi3.c
-- [x] modsi3.c
-- [x] muldf3.c
-- [x] muldi3.c
-- [x] mulodi4.c
-- [x] mulosi4.c
-- [x] mulsf3.c
-- [x] powidf2.c
-- [x] powisf2.c
-- [ ] riscv/muldi3.S
-- [ ] riscv/mulsi3.S
-- [x] subdf3.c
-- [x] subsf3.c
-- [x] truncdfsf2.c
-- [x] udivdi3.c
-- [x] udivmoddi4.c
-- [x] udivmodsi4.c
-- [x] udivsi3.c
-- [x] umoddi3.c
-- [x] umodsi3.c
-- [x] x86_64/chkstk.S
-
-These builtins are needed to support 128-bit integers.
-
-- [x] ashlti3.c
-- [x] ashrti3.c
-- [x] divti3.c
-- [x] fixdfti.c
-- [x] fixsfti.c
-- [x] fixunsdfti.c
-- [x] fixunssfti.c
-- [x] floattidf.c
-- [x] floattisf.c
-- [x] floatuntidf.c
-- [x] floatuntisf.c
-- [x] lshrti3.c
-- [x] modti3.c
-- [x] muloti4.c
-- [x] multi3.c
-- [x] udivmodti4.c
-- [x] udivti3.c
-- [x] umodti3.c
-
-These builtins are needed to support `f16` and `f128`, which are in the process
-of being added to Rust.
-
-- [x] addtf3.c
-- [x] comparetf2.c
-- [x] divtf3.c
-- [x] extenddftf2.c
-- [x] extendhfsf2.c
-- [x] extendhftf2.c
-- [x] extendsftf2.c
-- [x] fixtfdi.c
-- [x] fixtfsi.c
-- [x] fixtfti.c
-- [x] fixunstfdi.c
-- [x] fixunstfsi.c
-- [x] fixunstfti.c
-- [x] floatditf.c
-- [x] floatsitf.c
-- [x] floattitf.c
-- [x] floatunditf.c
-- [x] floatunsitf.c
-- [x] floatuntitf.c
-- [x] multf3.c
-- [x] powitf2.c
-- [x] subtf3.c
-- [x] truncdfhf2.c
-- [x] truncsfhf2.c
-- [x] trunctfdf2.c
-- [x] trunctfhf2.c
-- [x] trunctfsf2.c
-
-
-These builtins are used by the Hexagon DSP
-
-- [ ] hexagon/common_entry_exit_abi1.S
-- [ ] hexagon/common_entry_exit_abi2.S
-- [ ] hexagon/common_entry_exit_legacy.S
-- [x] hexagon/dfaddsub.S~~
-- [x] hexagon/dfdiv.S~~
-- [x] hexagon/dffma.S~~
-- [x] hexagon/dfminmax.S~~
-- [x] hexagon/dfmul.S~~
-- [x] hexagon/dfsqrt.S~~
-- [x] hexagon/divdi3.S~~
-- [x] hexagon/divsi3.S~~
-- [x] hexagon/fastmath2_dlib_asm.S~~
-- [x] hexagon/fastmath2_ldlib_asm.S~~
-- [x] hexagon/fastmath_dlib_asm.S~~
-- [x] hexagon/memcpy_forward_vp4cp4n2.S~~
-- [x] hexagon/memcpy_likely_aligned.S~~
-- [x] hexagon/moddi3.S~~
-- [x] hexagon/modsi3.S~~
-- [x] hexagon/sfdiv_opt.S~~
-- [x] hexagon/sfsqrt_opt.S~~
-- [x] hexagon/udivdi3.S~~
-- [x] hexagon/udivmoddi4.S~~
-- [x] hexagon/udivmodsi4.S~~
-- [x] hexagon/udivsi3.S~~
-- [x] hexagon/umoddi3.S~~
-- [x] hexagon/umodsi3.S~~
-
-## Unimplemented functions
-
-These builtins are for x87 `f80` floating-point numbers that are not supported
-by Rust.
-
-- ~~extendxftf2.c~~
-- ~~fixunsxfdi.c~~
-- ~~fixunsxfsi.c~~
-- ~~fixunsxfti.c~~
-- ~~fixxfdi.c~~
-- ~~fixxfti.c~~
-- ~~floatdixf.c~~
-- ~~floattixf.c~~
-- ~~floatundixf.c~~
-- ~~floatuntixf.c~~
-- ~~i386/floatdixf.S~~
-- ~~i386/floatundixf.S~~
-- ~~x86_64/floatdixf.c~~
-- ~~x86_64/floatundixf.S~~
-
-These builtins are for IBM "extended double" non-IEEE 128-bit floating-point
-numbers.
-
-- ~~ppc/divtc3.c~~
-- ~~ppc/fixtfdi.c~~
-- ~~ppc/fixtfti.c~~
-- ~~ppc/fixunstfdi.c~~
-- ~~ppc/fixunstfti.c~~
-- ~~ppc/floatditf.c~~
-- ~~ppc/floattitf.c~~
-- ~~ppc/floatunditf.c~~
-- ~~ppc/gcc_qadd.c~~
-- ~~ppc/gcc_qdiv.c~~
-- ~~ppc/gcc_qmul.c~~
-- ~~ppc/gcc_qsub.c~~
-- ~~ppc/multc3.c~~
-
-These builtins are for 16-bit brain floating-point numbers that are not
-supported by Rust.
-
-- ~~truncdfbf2.c~~
-- ~~truncsfbf2.c~~
-- ~~trunctfxf2.c~~
-
-These builtins involve complex floating-point types that are not supported by
-Rust.
-
-- ~~divdc3.c~~
-- ~~divsc3.c~~
-- ~~divtc3.c~~
-- ~~divxc3.c~~
-- ~~muldc3.c~~
-- ~~mulsc3.c~~
-- ~~multc3.c~~
-- ~~mulxc3.c~~
-- ~~powixf2.c~~
-
-These builtins are never called by LLVM.
-
-- ~~absvdi2.c~~
-- ~~absvsi2.c~~
-- ~~absvti2.c~~
-- ~~addvdi3.c~~
-- ~~addvsi3.c~~
-- ~~addvti3.c~~
-- ~~arm/aeabi_cdcmp.S~~
-- ~~arm/aeabi_cdcmpeq_check_nan.c~~
-- ~~arm/aeabi_cfcmp.S~~
-- ~~arm/aeabi_cfcmpeq_check_nan.c~~
-- ~~arm/aeabi_div0.c~~
-- ~~arm/aeabi_drsub.c~~
-- ~~arm/aeabi_frsub.c~~
-- ~~arm/aeabi_memcmp.S~~
-- ~~arm/bswapdi2.S~~
-- ~~arm/bswapsi2.S~~
-- ~~arm/clzdi2.S~~
-- ~~arm/clzsi2.S~~
-- ~~arm/comparesf2.S~~
-- ~~arm/restore_vfp_d8_d15_regs.S~~
-- ~~arm/save_vfp_d8_d15_regs.S~~
-- ~~arm/switch16.S~~
-- ~~arm/switch32.S~~
-- ~~arm/switch8.S~~
-- ~~arm/switchu8.S~~
-- ~~cmpdi2.c~~
-- ~~cmpti2.c~~
-- ~~ffssi2.c~~
-- ~~ffsdi2.c~~ - this is [called by gcc][jemalloc-fail] though!
-- ~~ffsti2.c~~
-- ~~mulvdi3.c~~
-- ~~mulvsi3.c~~
-- ~~mulvti3.c~~
-- ~~negdf2.c~~
-- ~~negdi2.c~~
-- ~~negsf2.c~~
-- ~~negti2.c~~
-- ~~negvdi2.c~~
-- ~~negvsi2.c~~
-- ~~negvti2.c~~
-- ~~paritydi2.c~~
-- ~~paritysi2.c~~
-- ~~parityti2.c~~
-- ~~popcountdi2.c~~
-- ~~popcountsi2.c~~
-- ~~popcountti2.c~~
-- ~~ppc/restFP.S~~
-- ~~ppc/saveFP.S~~
-- ~~subvdi3.c~~
-- ~~subvsi3.c~~
-- ~~subvti3.c~~
-- ~~ucmpdi2.c~~
-- ~~ucmpti2.c~~
-- ~~udivmodti4.c~~
-
-[jemalloc-fail]: https://travis-ci.org/rust-lang/rust/jobs/249772758
-
-Rust only exposes atomic types on platforms that support them, and therefore does not need to fall back to software implementations.
-
-- ~~arm/sync_fetch_and_add_4.S~~
-- ~~arm/sync_fetch_and_add_8.S~~
-- ~~arm/sync_fetch_and_and_4.S~~
-- ~~arm/sync_fetch_and_and_8.S~~
-- ~~arm/sync_fetch_and_max_4.S~~
-- ~~arm/sync_fetch_and_max_8.S~~
-- ~~arm/sync_fetch_and_min_4.S~~
-- ~~arm/sync_fetch_and_min_8.S~~
-- ~~arm/sync_fetch_and_nand_4.S~~
-- ~~arm/sync_fetch_and_nand_8.S~~
-- ~~arm/sync_fetch_and_or_4.S~~
-- ~~arm/sync_fetch_and_or_8.S~~
-- ~~arm/sync_fetch_and_sub_4.S~~
-- ~~arm/sync_fetch_and_sub_8.S~~
-- ~~arm/sync_fetch_and_umax_4.S~~
-- ~~arm/sync_fetch_and_umax_8.S~~
-- ~~arm/sync_fetch_and_umin_4.S~~
-- ~~arm/sync_fetch_and_umin_8.S~~
-- ~~arm/sync_fetch_and_xor_4.S~~
-- ~~arm/sync_fetch_and_xor_8.S~~
-- ~~arm/sync_synchronize.S~~
-- ~~atomic.c~~
-- ~~atomic_flag_clear.c~~
-- ~~atomic_flag_clear_explicit.c~~
-- ~~atomic_flag_test_and_set.c~~
-- ~~atomic_flag_test_and_set_explicit.c~~
-- ~~atomic_signal_fence.c~~
-- ~~atomic_thread_fence.c~~
-
-Miscellaneous functionality that is not used by Rust.
-
-- ~~aarch64/fp_mode.c~~
-- ~~aarch64/lse.S~~ (LSE atomics)
-- ~~aarch64/sme-abi-init.c~~ (matrix extension)
-- ~~aarch64/sme-abi.S~~ (matrix extension)
-- ~~aarch64/sme-libc-routines.c~~ (matrix extension)
-- ~~apple_versioning.c~~
-- ~~arm/fp_mode.c~~
-- ~~avr/exit.S~~
-- ~~clear_cache.c~~
-- ~~cpu_model/aarch64.c~~
-- ~~cpu_model/x86.c~~
-- ~~crtbegin.c~~
-- ~~crtend.c~~
-- ~~emutls.c~~
-- ~~enable_execute_stack.c~~
-- ~~eprintf.c~~
-- ~~fp_mode.c~~ (float exception handling)
-- ~~gcc_personality_v0.c~~
-- ~~i386/fp_mode.c~~
-- ~~int_util.c~~
-- ~~loongarch/fp_mode.c~~
-- ~~os_version_check.c~~
-- ~~riscv/fp_mode.c~~
-- ~~riscv/restore.S~~ (callee-saved registers)
-- ~~riscv/save.S~~ (callee-saved registers)
-- ~~trampoline_setup.c~~
-- ~~ve/grow_stack.S~~
-- ~~ve/grow_stack_align.S~~
-
-Floating-point implementations of builtins that are only called from soft-float code. It would be better to simply use the generic soft-float versions in this case.
-
-- ~~i386/floatdidf.S~~
-- ~~i386/floatdisf.S~~
-- ~~i386/floatundidf.S~~
-- ~~i386/floatundisf.S~~
-- ~~x86_64/floatundidf.S~~
-- ~~x86_64/floatundisf.S~~
-- ~~x86_64/floatdidf.c~~
-- ~~x86_64/floatdisf.c~~
-
-Unsupported in any current target: used on old versions of 32-bit iOS with ARMv5.
-
-- ~~arm/adddf3vfp.S~~
-- ~~arm/addsf3vfp.S~~
-- ~~arm/divdf3vfp.S~~
-- ~~arm/divsf3vfp.S~~
-- ~~arm/eqdf2vfp.S~~
-- ~~arm/eqsf2vfp.S~~
-- ~~arm/extendsfdf2vfp.S~~
-- ~~arm/fixdfsivfp.S~~
-- ~~arm/fixsfsivfp.S~~
-- ~~arm/fixunsdfsivfp.S~~
-- ~~arm/fixunssfsivfp.S~~
-- ~~arm/floatsidfvfp.S~~
-- ~~arm/floatsisfvfp.S~~
-- ~~arm/floatunssidfvfp.S~~
-- ~~arm/floatunssisfvfp.S~~
-- ~~arm/gedf2vfp.S~~
-- ~~arm/gesf2vfp.S~~
-- ~~arm/gtdf2vfp.S~~
-- ~~arm/gtsf2vfp.S~~
-- ~~arm/ledf2vfp.S~~
-- ~~arm/lesf2vfp.S~~
-- ~~arm/ltdf2vfp.S~~
-- ~~arm/ltsf2vfp.S~~
-- ~~arm/muldf3vfp.S~~
-- ~~arm/mulsf3vfp.S~~
-- ~~arm/nedf2vfp.S~~
-- ~~arm/negdf2vfp.S~~
-- ~~arm/negsf2vfp.S~~
-- ~~arm/nesf2vfp.S~~
-- ~~arm/subdf3vfp.S~~
-- ~~arm/subsf3vfp.S~~
-- ~~arm/truncdfsf2vfp.S~~
-- ~~arm/unorddf2vfp.S~~
-- ~~arm/unordsf2vfp.S~~
+For instructions on contributing, see [CONTRIBUTING.md](CONTRIBUTING.md).
 
 ## License
 
-The compiler-builtins crate is dual licensed under both the University of
-Illinois "BSD-Like" license and the MIT license.  As a user of this code you may
-choose to use it under either license.  As a contributor, you agree to allow
-your code to be used under both.
+* `libm` may be used under the [MIT License]
+* `compiler-builtins` may be used under the [MIT License] and the
+  [Apache License, Version 2.0] with the LLVM exception.
+* All original contributions must be under all of: the MIT license, the
+  Apache-2.0 license, and the Apache-2.0 license with the LLVM exception.
+
+More details are in [LICENSE.txt](LICENSE.txt) and
+[libm/LICENSE.txt](libm/LICENSE.txt).
 
-Full text of the relevant licenses is in LICENSE.TXT.
+[MIT License]: https://opensource.org/license/mit
+[Apache License, Version 2.0]: htps://www.apache.org/licenses/LICENSE-2.0
diff --git a/builtins-test-intrinsics/Cargo.toml b/builtins-test-intrinsics/Cargo.toml
index 6d88cbec9..6e10628a4 100644
--- a/builtins-test-intrinsics/Cargo.toml
+++ b/builtins-test-intrinsics/Cargo.toml
@@ -3,6 +3,7 @@ name = "builtins-test-intrinsics"
 version = "0.1.0"
 edition = "2021"
 publish = false
+license = "MIT OR Apache-2.0"
 
 [dependencies]
 compiler_builtins = { path = "../compiler-builtins", features = ["compiler-builtins"]}
diff --git a/builtins-test/Cargo.toml b/builtins-test/Cargo.toml
index 18185d8fe..f7bcb52b4 100644
--- a/builtins-test/Cargo.toml
+++ b/builtins-test/Cargo.toml
@@ -4,6 +4,7 @@ version = "0.1.0"
 authors = ["Alex Crichton <alex@alexcrichton.com>"]
 edition = "2024"
 publish = false
+license = "MIT AND Apache-2.0 WITH LLVM-exception AND (MIT OR Apache-2.0)"
 
 [dependencies]
 # For fuzzing tests we want a deterministic seedable RNG. We also eliminate potential
diff --git a/compiler-builtins/Cargo.toml b/compiler-builtins/Cargo.toml
index a014baf04..1de37bd86 100644
--- a/compiler-builtins/Cargo.toml
+++ b/compiler-builtins/Cargo.toml
@@ -3,25 +3,12 @@ authors = ["Jorge Aparicio <japaricious@gmail.com>"]
 name = "compiler_builtins"
 version = "0.1.155"
 license = "MIT AND Apache-2.0 WITH LLVM-exception AND (MIT OR Apache-2.0)"
-readme = "../README.md"
+readme = "README.md"
 repository = "https://github.com/rust-lang/compiler-builtins"
 homepage = "https://github.com/rust-lang/compiler-builtins"
 documentation = "https://docs.rs/compiler_builtins"
 edition = "2021"
-description = """
-Compiler intrinsics used by the Rust compiler. Also available for other targets
-if necessary!
-"""
-include = [
-  '/Cargo.toml',
-  '/build.rs',
-  '/configure.rs',
-  '/src/*',
-  '../LICENSE.txt',
-  '../README.md',
-  '../compiler-rt/*',
-  'libm/src/math/*',
-]
+description = "Compiler intrinsics used by the Rust compiler."
 links = 'compiler-rt'
 
 [lib]
diff --git a/compiler-builtins/LICENSE.txt b/compiler-builtins/LICENSE.txt
new file mode 120000
index 000000000..4ab43736a
--- /dev/null
+++ b/compiler-builtins/LICENSE.txt
@@ -0,0 +1 @@
+../LICENSE.txt
\ No newline at end of file
diff --git a/compiler-builtins/README.md b/compiler-builtins/README.md
new file mode 100644
index 000000000..387b70c04
--- /dev/null
+++ b/compiler-builtins/README.md
@@ -0,0 +1,436 @@
+# `compiler-builtins`
+
+This crate provides external symbols that the compiler expects to be available
+when building Rust projects, typically software routines for basic operations
+that do not have hardware support. It is largely a port of LLVM's
+[`compiler-rt`].
+
+It is distributed as part of Rust's sysroot. `compiler-builtins` does not need
+to be added as an explicit dependency in `Cargo.toml`.
+
+[`compiler-rt`]: https://github.com/llvm/llvm-project/tree/1b1dc505057322f4fa1110ef4f53c44347f52986/compiler-rt
+
+## Contributing
+
+See [CONTRIBUTING.md](CONTRIBUTING.md).
+
+## Progress
+
+- [x] aarch64/chkstk.S
+- [x] adddf3.c
+- [x] addsf3.c
+- [x] arm/addsf3.S
+- [x] arm/aeabi_dcmp.S
+- [x] arm/aeabi_fcmp.S
+- [x] arm/aeabi_idivmod.S
+- [x] arm/aeabi_ldivmod.S
+- [x] arm/aeabi_memcpy.S
+- [x] arm/aeabi_memmove.S
+- [x] arm/aeabi_memset.S
+- [x] arm/aeabi_uidivmod.S
+- [x] arm/aeabi_uldivmod.S
+- [ ] arm/chkstk.S
+- [ ] arm/divmodsi4.S (generic version is done)
+- [ ] arm/divsi3.S (generic version is done)
+- [ ] arm/modsi3.S (generic version is done)
+- [x] arm/softfloat-alias.list
+- [ ] arm/udivmodsi4.S (generic version is done)
+- [ ] arm/udivsi3.S (generic version is done)
+- [ ] arm/umodsi3.S (generic version is done)
+- [x] ashldi3.c
+- [x] ashrdi3.c
+- [ ] avr/divmodhi4.S
+- [ ] avr/divmodqi4.S
+- [ ] avr/mulhi3.S
+- [ ] avr/mulqi3.S
+- [ ] avr/udivmodhi4.S
+- [ ] avr/udivmodqi4.S
+- [x] bswapdi2.c
+- [x] bswapsi2.c
+- [x] bswapti2.c
+- [x] clzdi2.c
+- [x] clzsi2.c
+- [x] clzti2.c
+- [x] comparedf2.c
+- [x] comparesf2.c
+- [x] ctzdi2.c
+- [x] ctzsi2.c
+- [x] ctzti2.c
+- [x] divdf3.c
+- [x] divdi3.c
+- [x] divmoddi4.c
+- [x] divmodsi4.c
+- [x] divmodti4.c
+- [x] divsf3.c
+- [x] divsi3.c
+- [x] extendsfdf2.c
+- [x] fixdfdi.c
+- [x] fixdfsi.c
+- [x] fixsfdi.c
+- [x] fixsfsi.c
+- [x] fixunsdfdi.c
+- [x] fixunsdfsi.c
+- [x] fixunssfdi.c
+- [x] fixunssfsi.c
+- [x] floatdidf.c
+- [x] floatdisf.c
+- [x] floatsidf.c
+- [x] floatsisf.c
+- [x] floatundidf.c
+- [x] floatundisf.c
+- [x] floatunsidf.c
+- [x] floatunsisf.c
+- [ ] i386/ashldi3.S
+- [ ] i386/ashrdi3.S
+- [x] i386/chkstk.S
+- [ ] i386/divdi3.S
+- [ ] i386/lshrdi3.S
+- [ ] i386/moddi3.S
+- [ ] i386/muldi3.S
+- [ ] i386/udivdi3.S
+- [ ] i386/umoddi3.S
+- [x] lshrdi3.c
+- [x] moddi3.c
+- [x] modsi3.c
+- [x] muldf3.c
+- [x] muldi3.c
+- [x] mulodi4.c
+- [x] mulosi4.c
+- [x] mulsf3.c
+- [x] powidf2.c
+- [x] powisf2.c
+- [ ] riscv/muldi3.S
+- [ ] riscv/mulsi3.S
+- [x] subdf3.c
+- [x] subsf3.c
+- [x] truncdfsf2.c
+- [x] udivdi3.c
+- [x] udivmoddi4.c
+- [x] udivmodsi4.c
+- [x] udivsi3.c
+- [x] umoddi3.c
+- [x] umodsi3.c
+- [x] x86_64/chkstk.S
+
+These builtins are needed to support 128-bit integers.
+
+- [x] ashlti3.c
+- [x] ashrti3.c
+- [x] divti3.c
+- [x] fixdfti.c
+- [x] fixsfti.c
+- [x] fixunsdfti.c
+- [x] fixunssfti.c
+- [x] floattidf.c
+- [x] floattisf.c
+- [x] floatuntidf.c
+- [x] floatuntisf.c
+- [x] lshrti3.c
+- [x] modti3.c
+- [x] muloti4.c
+- [x] multi3.c
+- [x] udivmodti4.c
+- [x] udivti3.c
+- [x] umodti3.c
+
+These builtins are needed to support `f16` and `f128`, which are in the process
+of being added to Rust.
+
+- [x] addtf3.c
+- [x] comparetf2.c
+- [x] divtf3.c
+- [x] extenddftf2.c
+- [x] extendhfsf2.c
+- [x] extendhftf2.c
+- [x] extendsftf2.c
+- [x] fixtfdi.c
+- [x] fixtfsi.c
+- [x] fixtfti.c
+- [x] fixunstfdi.c
+- [x] fixunstfsi.c
+- [x] fixunstfti.c
+- [x] floatditf.c
+- [x] floatsitf.c
+- [x] floattitf.c
+- [x] floatunditf.c
+- [x] floatunsitf.c
+- [x] floatuntitf.c
+- [x] multf3.c
+- [x] powitf2.c
+- [x] subtf3.c
+- [x] truncdfhf2.c
+- [x] truncsfhf2.c
+- [x] trunctfdf2.c
+- [x] trunctfhf2.c
+- [x] trunctfsf2.c
+
+
+These builtins are used by the Hexagon DSP
+
+- [ ] hexagon/common_entry_exit_abi1.S
+- [ ] hexagon/common_entry_exit_abi2.S
+- [ ] hexagon/common_entry_exit_legacy.S
+- [x] hexagon/dfaddsub.S~~
+- [x] hexagon/dfdiv.S~~
+- [x] hexagon/dffma.S~~
+- [x] hexagon/dfminmax.S~~
+- [x] hexagon/dfmul.S~~
+- [x] hexagon/dfsqrt.S~~
+- [x] hexagon/divdi3.S~~
+- [x] hexagon/divsi3.S~~
+- [x] hexagon/fastmath2_dlib_asm.S~~
+- [x] hexagon/fastmath2_ldlib_asm.S~~
+- [x] hexagon/fastmath_dlib_asm.S~~
+- [x] hexagon/memcpy_forward_vp4cp4n2.S~~
+- [x] hexagon/memcpy_likely_aligned.S~~
+- [x] hexagon/moddi3.S~~
+- [x] hexagon/modsi3.S~~
+- [x] hexagon/sfdiv_opt.S~~
+- [x] hexagon/sfsqrt_opt.S~~
+- [x] hexagon/udivdi3.S~~
+- [x] hexagon/udivmoddi4.S~~
+- [x] hexagon/udivmodsi4.S~~
+- [x] hexagon/udivsi3.S~~
+- [x] hexagon/umoddi3.S~~
+- [x] hexagon/umodsi3.S~~
+
+## Unimplemented functions
+
+These builtins are for x87 `f80` floating-point numbers that are not supported
+by Rust.
+
+- ~~extendxftf2.c~~
+- ~~fixunsxfdi.c~~
+- ~~fixunsxfsi.c~~
+- ~~fixunsxfti.c~~
+- ~~fixxfdi.c~~
+- ~~fixxfti.c~~
+- ~~floatdixf.c~~
+- ~~floattixf.c~~
+- ~~floatundixf.c~~
+- ~~floatuntixf.c~~
+- ~~i386/floatdixf.S~~
+- ~~i386/floatundixf.S~~
+- ~~x86_64/floatdixf.c~~
+- ~~x86_64/floatundixf.S~~
+
+These builtins are for IBM "extended double" non-IEEE 128-bit floating-point
+numbers.
+
+- ~~ppc/divtc3.c~~
+- ~~ppc/fixtfdi.c~~
+- ~~ppc/fixtfti.c~~
+- ~~ppc/fixunstfdi.c~~
+- ~~ppc/fixunstfti.c~~
+- ~~ppc/floatditf.c~~
+- ~~ppc/floattitf.c~~
+- ~~ppc/floatunditf.c~~
+- ~~ppc/gcc_qadd.c~~
+- ~~ppc/gcc_qdiv.c~~
+- ~~ppc/gcc_qmul.c~~
+- ~~ppc/gcc_qsub.c~~
+- ~~ppc/multc3.c~~
+
+These builtins are for 16-bit brain floating-point numbers that are not
+supported by Rust.
+
+- ~~truncdfbf2.c~~
+- ~~truncsfbf2.c~~
+- ~~trunctfxf2.c~~
+
+These builtins involve complex floating-point types that are not supported by
+Rust.
+
+- ~~divdc3.c~~
+- ~~divsc3.c~~
+- ~~divtc3.c~~
+- ~~divxc3.c~~
+- ~~muldc3.c~~
+- ~~mulsc3.c~~
+- ~~multc3.c~~
+- ~~mulxc3.c~~
+- ~~powixf2.c~~
+
+These builtins are never called by LLVM.
+
+- ~~absvdi2.c~~
+- ~~absvsi2.c~~
+- ~~absvti2.c~~
+- ~~addvdi3.c~~
+- ~~addvsi3.c~~
+- ~~addvti3.c~~
+- ~~arm/aeabi_cdcmp.S~~
+- ~~arm/aeabi_cdcmpeq_check_nan.c~~
+- ~~arm/aeabi_cfcmp.S~~
+- ~~arm/aeabi_cfcmpeq_check_nan.c~~
+- ~~arm/aeabi_div0.c~~
+- ~~arm/aeabi_drsub.c~~
+- ~~arm/aeabi_frsub.c~~
+- ~~arm/aeabi_memcmp.S~~
+- ~~arm/bswapdi2.S~~
+- ~~arm/bswapsi2.S~~
+- ~~arm/clzdi2.S~~
+- ~~arm/clzsi2.S~~
+- ~~arm/comparesf2.S~~
+- ~~arm/restore_vfp_d8_d15_regs.S~~
+- ~~arm/save_vfp_d8_d15_regs.S~~
+- ~~arm/switch16.S~~
+- ~~arm/switch32.S~~
+- ~~arm/switch8.S~~
+- ~~arm/switchu8.S~~
+- ~~cmpdi2.c~~
+- ~~cmpti2.c~~
+- ~~ffssi2.c~~
+- ~~ffsdi2.c~~ - this is [called by gcc][jemalloc-fail] though!
+- ~~ffsti2.c~~
+- ~~mulvdi3.c~~
+- ~~mulvsi3.c~~
+- ~~mulvti3.c~~
+- ~~negdf2.c~~
+- ~~negdi2.c~~
+- ~~negsf2.c~~
+- ~~negti2.c~~
+- ~~negvdi2.c~~
+- ~~negvsi2.c~~
+- ~~negvti2.c~~
+- ~~paritydi2.c~~
+- ~~paritysi2.c~~
+- ~~parityti2.c~~
+- ~~popcountdi2.c~~
+- ~~popcountsi2.c~~
+- ~~popcountti2.c~~
+- ~~ppc/restFP.S~~
+- ~~ppc/saveFP.S~~
+- ~~subvdi3.c~~
+- ~~subvsi3.c~~
+- ~~subvti3.c~~
+- ~~ucmpdi2.c~~
+- ~~ucmpti2.c~~
+- ~~udivmodti4.c~~
+
+[jemalloc-fail]: https://travis-ci.org/rust-lang/rust/jobs/249772758
+
+Rust only exposes atomic types on platforms that support them, and therefore does not need to fall back to software implementations.
+
+- ~~arm/sync_fetch_and_add_4.S~~
+- ~~arm/sync_fetch_and_add_8.S~~
+- ~~arm/sync_fetch_and_and_4.S~~
+- ~~arm/sync_fetch_and_and_8.S~~
+- ~~arm/sync_fetch_and_max_4.S~~
+- ~~arm/sync_fetch_and_max_8.S~~
+- ~~arm/sync_fetch_and_min_4.S~~
+- ~~arm/sync_fetch_and_min_8.S~~
+- ~~arm/sync_fetch_and_nand_4.S~~
+- ~~arm/sync_fetch_and_nand_8.S~~
+- ~~arm/sync_fetch_and_or_4.S~~
+- ~~arm/sync_fetch_and_or_8.S~~
+- ~~arm/sync_fetch_and_sub_4.S~~
+- ~~arm/sync_fetch_and_sub_8.S~~
+- ~~arm/sync_fetch_and_umax_4.S~~
+- ~~arm/sync_fetch_and_umax_8.S~~
+- ~~arm/sync_fetch_and_umin_4.S~~
+- ~~arm/sync_fetch_and_umin_8.S~~
+- ~~arm/sync_fetch_and_xor_4.S~~
+- ~~arm/sync_fetch_and_xor_8.S~~
+- ~~arm/sync_synchronize.S~~
+- ~~atomic.c~~
+- ~~atomic_flag_clear.c~~
+- ~~atomic_flag_clear_explicit.c~~
+- ~~atomic_flag_test_and_set.c~~
+- ~~atomic_flag_test_and_set_explicit.c~~
+- ~~atomic_signal_fence.c~~
+- ~~atomic_thread_fence.c~~
+
+Miscellaneous functionality that is not used by Rust.
+
+- ~~aarch64/fp_mode.c~~
+- ~~aarch64/lse.S~~ (LSE atomics)
+- ~~aarch64/sme-abi-init.c~~ (matrix extension)
+- ~~aarch64/sme-abi.S~~ (matrix extension)
+- ~~aarch64/sme-libc-routines.c~~ (matrix extension)
+- ~~apple_versioning.c~~
+- ~~arm/fp_mode.c~~
+- ~~avr/exit.S~~
+- ~~clear_cache.c~~
+- ~~cpu_model/aarch64.c~~
+- ~~cpu_model/x86.c~~
+- ~~crtbegin.c~~
+- ~~crtend.c~~
+- ~~emutls.c~~
+- ~~enable_execute_stack.c~~
+- ~~eprintf.c~~
+- ~~fp_mode.c~~ (float exception handling)
+- ~~gcc_personality_v0.c~~
+- ~~i386/fp_mode.c~~
+- ~~int_util.c~~
+- ~~loongarch/fp_mode.c~~
+- ~~os_version_check.c~~
+- ~~riscv/fp_mode.c~~
+- ~~riscv/restore.S~~ (callee-saved registers)
+- ~~riscv/save.S~~ (callee-saved registers)
+- ~~trampoline_setup.c~~
+- ~~ve/grow_stack.S~~
+- ~~ve/grow_stack_align.S~~
+
+Floating-point implementations of builtins that are only called from soft-float code. It would be better to simply use the generic soft-float versions in this case.
+
+- ~~i386/floatdidf.S~~
+- ~~i386/floatdisf.S~~
+- ~~i386/floatundidf.S~~
+- ~~i386/floatundisf.S~~
+- ~~x86_64/floatundidf.S~~
+- ~~x86_64/floatundisf.S~~
+- ~~x86_64/floatdidf.c~~
+- ~~x86_64/floatdisf.c~~
+
+Unsupported in any current target: used on old versions of 32-bit iOS with ARMv5.
+
+- ~~arm/adddf3vfp.S~~
+- ~~arm/addsf3vfp.S~~
+- ~~arm/divdf3vfp.S~~
+- ~~arm/divsf3vfp.S~~
+- ~~arm/eqdf2vfp.S~~
+- ~~arm/eqsf2vfp.S~~
+- ~~arm/extendsfdf2vfp.S~~
+- ~~arm/fixdfsivfp.S~~
+- ~~arm/fixsfsivfp.S~~
+- ~~arm/fixunsdfsivfp.S~~
+- ~~arm/fixunssfsivfp.S~~
+- ~~arm/floatsidfvfp.S~~
+- ~~arm/floatsisfvfp.S~~
+- ~~arm/floatunssidfvfp.S~~
+- ~~arm/floatunssisfvfp.S~~
+- ~~arm/gedf2vfp.S~~
+- ~~arm/gesf2vfp.S~~
+- ~~arm/gtdf2vfp.S~~
+- ~~arm/gtsf2vfp.S~~
+- ~~arm/ledf2vfp.S~~
+- ~~arm/lesf2vfp.S~~
+- ~~arm/ltdf2vfp.S~~
+- ~~arm/ltsf2vfp.S~~
+- ~~arm/muldf3vfp.S~~
+- ~~arm/mulsf3vfp.S~~
+- ~~arm/nedf2vfp.S~~
+- ~~arm/negdf2vfp.S~~
+- ~~arm/negsf2vfp.S~~
+- ~~arm/nesf2vfp.S~~
+- ~~arm/subdf3vfp.S~~
+- ~~arm/subsf3vfp.S~~
+- ~~arm/truncdfsf2vfp.S~~
+- ~~arm/unorddf2vfp.S~~
+- ~~arm/unordsf2vfp.S~~
+
+## License
+
+Usage is allowed under the [MIT License] and the [Apache License, Version 2.0]
+with the LLVM exception.
+
+[MIT License]: https://opensource.org/license/mit
+[Apache License, Version 2.0]: htps://www.apache.org/licenses/LICENSE-2.0
+
+### Contribution
+
+Contributions are licensed under the MIT License, the Apache License,
+Version 2.0, and the Apache-2.0 license with the LLVM exception.
+
+See [LICENSE.txt](../LICENSE.txt) for full details.
diff --git a/compiler-builtins/src/lib.rs b/compiler-builtins/src/lib.rs
index 067855603..7523a00cf 100644
--- a/compiler-builtins/src/lib.rs
+++ b/compiler-builtins/src/lib.rs
@@ -45,7 +45,7 @@ pub mod math;
 pub mod mem;
 
 // `libm` expects its `support` module to be available in the crate root.
-use math::libm::support;
+use math::libm_math::support;
 
 #[cfg(target_arch = "arm")]
 pub mod arm;
diff --git a/compiler-builtins/src/math/libm_math b/compiler-builtins/src/math/libm_math
new file mode 120000
index 000000000..4d65313c2
--- /dev/null
+++ b/compiler-builtins/src/math/libm_math
@@ -0,0 +1 @@
+../../../libm/src/math
\ No newline at end of file
diff --git a/compiler-builtins/src/math.rs b/compiler-builtins/src/math/mod.rs
similarity index 96%
rename from compiler-builtins/src/math.rs
rename to compiler-builtins/src/math/mod.rs
index 722374f8e..078feb9ff 100644
--- a/compiler-builtins/src/math.rs
+++ b/compiler-builtins/src/math/mod.rs
@@ -2,15 +2,14 @@
 #[allow(dead_code)]
 #[allow(unused_imports)]
 #[allow(clippy::all)]
-#[path = "../../libm/src/math/mod.rs"]
-pub(crate) mod libm;
+pub(crate) mod libm_math;
 
 macro_rules! libm_intrinsics {
     ($(fn $fun:ident($($iid:ident : $ity:ty),+) -> $oty:ty;)+) => {
         intrinsics! {
             $(
                 pub extern "C" fn $fun($($iid: $ity),+) -> $oty {
-                    $crate::math::libm::$fun($($iid),+)
+                    $crate::math::libm_math::$fun($($iid),+)
                 }
             )+
         }
@@ -185,13 +184,13 @@ pub mod partial_availability {
     // allow for windows (and other targets)
     intrinsics! {
         pub extern "C" fn lgamma_r(x: f64, s: &mut i32) -> f64 {
-            let r = super::libm::lgamma_r(x);
+            let r = super::libm_math::lgamma_r(x);
             *s = r.1;
             r.0
         }
 
         pub extern "C" fn lgammaf_r(x: f32, s: &mut i32) -> f32 {
-            let r = super::libm::lgammaf_r(x);
+            let r = super::libm_math::lgammaf_r(x);
             *s = r.1;
             r.0
         }
diff --git a/crates/libm-macros/Cargo.toml b/crates/libm-macros/Cargo.toml
index 50c869db7..3929854f0 100644
--- a/crates/libm-macros/Cargo.toml
+++ b/crates/libm-macros/Cargo.toml
@@ -3,6 +3,7 @@ name = "libm-macros"
 version = "0.1.0"
 edition = "2024"
 publish = false
+license = "MIT OR Apache-2.0"
 
 [lib]
 proc-macro = true
diff --git a/crates/musl-math-sys/Cargo.toml b/crates/musl-math-sys/Cargo.toml
index 9e866a970..d3fb147e5 100644
--- a/crates/musl-math-sys/Cargo.toml
+++ b/crates/musl-math-sys/Cargo.toml
@@ -3,6 +3,7 @@ name = "musl-math-sys"
 version = "0.1.0"
 edition = "2024"
 publish = false
+license = "MIT OR Apache-2.0"
 
 [dependencies]
 
diff --git a/crates/util/Cargo.toml b/crates/util/Cargo.toml
index ae37a7238..614c54bd8 100644
--- a/crates/util/Cargo.toml
+++ b/crates/util/Cargo.toml
@@ -3,6 +3,7 @@ name = "util"
 version = "0.1.0"
 edition = "2024"
 publish = false
+license = "MIT OR Apache-2.0"
 
 [features]
 default = ["build-musl", "build-mpfr", "unstable-float"]
diff --git a/libm-test/Cargo.toml b/libm-test/Cargo.toml
index 6fd49774e..7a306e735 100644
--- a/libm-test/Cargo.toml
+++ b/libm-test/Cargo.toml
@@ -3,6 +3,7 @@ name = "libm-test"
 version = "0.1.0"
 edition = "2024"
 publish = false
+license = "MIT OR Apache-2.0"
 
 [features]
 default = ["build-mpfr", "build-musl", "unstable-float"]
diff --git a/libm/CONTRIBUTING.md b/libm/CONTRIBUTING.md
deleted file mode 100644
index dc4006035..000000000
--- a/libm/CONTRIBUTING.md
+++ /dev/null
@@ -1,82 +0,0 @@
-# How to contribute
-
-- Pick your favorite math function from the [issue tracker].
-- Look for the C implementation of the function in the [MUSL source code][src].
-- Copy paste the C code into a Rust file in the `src/math` directory and adjust
-  `src/math/mod.rs` accordingly. Also, uncomment the corresponding trait method
-  in `src/lib.rs`.
-- Write some simple tests in your module (using `#[test]`)
-- Run `cargo test` to make sure it works. Full tests are only run when enabling
-  features, see [Testing](#testing) below.
-- Send us a pull request! Make sure to run `cargo fmt` on your code before
-  sending the PR. Also include "closes #42" in the PR description to close the
-  corresponding issue.
-- :tada:
-
-[issue tracker]: https://github.com/rust-lang/libm/issues
-[src]: https://git.musl-libc.org/cgit/musl/tree/src/math
-[`src/math/truncf.rs`]: https://github.com/rust-lang/libm/blob/master/src/math/truncf.rs
-
-Check [PR #65] for an example.
-
-[PR #65]: https://github.com/rust-lang/libm/pull/65
-
-## Tips and tricks
-
-- *IMPORTANT* The code in this crate will end up being used in the `core` crate so it can **not**
-  have any external dependencies (other than `core` itself).
-
-- Only use relative imports within the `math` directory / module, e.g. `use self::fabs::fabs` or
-`use super::k_cos`. Absolute imports from core are OK, e.g. `use core::u64`.
-
-- To reinterpret a float as an integer use the `to_bits` method. The MUSL code uses the
-  `GET_FLOAT_WORD` macro, or a union, to do this operation.
-
-- To reinterpret an integer as a float use the `f32::from_bits` constructor. The MUSL code uses the
-  `SET_FLOAT_WORD` macro, or a union, to do this operation.
-
-- You may use other methods from core like `f64::is_nan`, etc. as appropriate.
-
-- If you're implementing one of the private double-underscore functions, take a look at the
-  "source" name in the comment at the top for an idea for alternate naming. For example, `__sin`
-  was renamed to `k_sin` after the FreeBSD source code naming. Do `use` these private functions in
-  `mod.rs`.
-
-- You may encounter weird literals like `0x1p127f` in the MUSL code. These are hexadecimal floating
-  point literals. Rust (the language) doesn't support these kind of literals. This crate provides
-  two macros, `hf32!` and `hf64!`, which convert string literals to floats at compile time.
-
-  ```rust
-  assert_eq!(hf32!("0x1.ffep+8").to_bits(), 0x43fff000);
-  assert_eq!(hf64!("0x1.ffep+8").to_bits(), 0x407ffe0000000000);
-  ```
-
-- Rust code panics on arithmetic overflows when not optimized. You may need to use the [`Wrapping`]
-  newtype to avoid this problem, or individual methods like [`wrapping_add`].
-
-[`Wrapping`]: https://doc.rust-lang.org/std/num/struct.Wrapping.html
-[`wrapping_add`]: https://doc.rust-lang.org/std/primitive.u32.html#method.wrapping_add
-
-## Testing
-
-Normal tests can be executed with:
-
-```sh
-# Tests against musl require that the submodule is up to date.
-git submodule init
-git submodule update
-
-# `--release` ables more test cases
-cargo test --release
-```
-
-If you are on a system that cannot build musl or MPFR, passing
-`--no-default-features` will run some limited tests.
-
-The multiprecision tests use the [`rug`] crate for bindings to MPFR. MPFR can
-be difficult to build on non-Unix systems, refer to [`gmp_mpfr_sys`] for help.
-
-`build-musl` does not build with MSVC, Wasm, or Thumb.
-
-[`rug`]: https://docs.rs/rug/latest/rug/
-[`gmp_mpfr_sys`]: https://docs.rs/gmp-mpfr-sys/1.6.4/gmp_mpfr_sys/
diff --git a/libm/Cargo.toml b/libm/Cargo.toml
index 44154c1a8..4e3850bbf 100644
--- a/libm/Cargo.toml
+++ b/libm/Cargo.toml
@@ -7,7 +7,7 @@ keywords = ["libm", "math"]
 license = "MIT"
 name = "libm"
 readme = "README.md"
-repository = "https://github.com/rust-lang/libm"
+repository = "https://github.com/rust-lang/compiler-builtins"
 version = "0.2.11"
 edition = "2021"
 rust-version = "1.63"
diff --git a/libm/README.md b/libm/README.md
index 52d760a4f..349e892df 100644
--- a/libm/README.md
+++ b/libm/README.md
@@ -1,38 +1,26 @@
 # `libm`
 
-A port of [MUSL]'s libm to Rust.
+A Rust implementations of the C math library.
 
-[MUSL]: https://musl.libc.org/
+## Usage
 
-## Goals
+`libm` provides fallback implementations for Rust's [float math functions] in
+`core`, and the [`core_float_math`] feature. If what is available suits your
+needs, there is no need to add `libm` as a dependency.
 
-The short term goal of this library is to [enable math support (e.g. `sin`, `atan2`) for the
-`wasm32-unknown-unknown` target][wasm] (cf. [rust-lang/compiler-builtins][pr]). The longer
-term goal is to enable [math support in the `core` crate][core].
+If more functionality is needed, this crate can also be used directly:
 
-[wasm]: https://github.com/rust-lang/libm/milestone/1
-[pr]: https://github.com/rust-lang/compiler-builtins/pull/248
-[core]: https://github.com/rust-lang/libm/milestone/2
+```toml
+[dependencies]
+libm = "0.2.11"
+```
 
-## Already usable
-
-This crate is [on crates.io] and can be used today in stable `#![no_std]` programs.
-
-The API documentation can be found [here](https://docs.rs/libm).
-
-[on crates.io]: https://crates.io/crates/libm
-
-## Benchmark
-[benchmark]: #benchmark
-
-The benchmarks are located in `crates/libm-bench` and require a nightly Rust toolchain.
-To run all benchmarks:
-
-> cargo +nightly bench --all
+[float math functions]: https://doc.rust-lang.org/std/primitive.f32.html
+[`core_float_math`]: https://github.com/rust-lang/rust/issues/137578
 
 ## Contributing
 
-Please check [CONTRIBUTING.md](CONTRIBUTING.md)
+Please check [CONTRIBUTING.md](../CONTRIBUTING.md)
 
 ## Minimum Rust version policy
 
@@ -40,17 +28,15 @@ This crate supports rustc 1.63 and newer.
 
 ## License
 
-Usage is licensed under the MIT license ([LICENSE-MIT](LICENSE-MIT) or
-https://opensource.org/licenses/MIT).
-
+Usage is under the MIT license, available at
+<https://opensource.org/license/mit>.
 
 ### Contribution
 
 Contributions are licensed under both the MIT license and the Apache License,
-Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or
-https://www.apache.org/licenses/LICENSE-2.0). Unless you explicitly state
-otherwise, any contribution intentionally submitted for inclusion in the work
-by you, as defined in the Apache-2.0 license, shall be dual licensed as
-mentioned, without any additional terms or conditions.
+Version 2.0, available at <htps://www.apache.org/licenses/LICENSE-2.0>. Unless
+you explicitly state otherwise, any contribution intentionally submitted for
+inclusion in the work by you, as defined in the Apache-2.0 license, shall be
+dual licensed as mentioned, without any additional terms or conditions.
 
-See `LICENSE.txt` for full details.
+See [LICENSE.txt](LICENSE.txt) for full details.