refactor: Move the libm crate to a subdirectory

In preparation for switching to a virtual manifest, move the `libm`
crate into a subdirectory and update paths to match.

Updating `Cargo.toml` is done in the next commit so git tracks the moved
file correctly.

library/compiler-builtins/libm/.github/workflows/main.yaml

@@ -213,7 +213,7 @@ jobs:
     steps:
     - uses: actions/checkout@master
     - run: |
-        msrv="$(perl -ne 'print if s/rust-version\s*=\s*"(.*)"/\1/g' Cargo.toml)"
+        msrv="$(perl -ne 'print if s/rust-version\s*=\s*"(.*)"/\1/g' libm/Cargo.toml)"
         echo "MSRV: $msrv"
         echo "MSRV=$msrv" >> "$GITHUB_ENV"
     - name: Install Rust

library/compiler-builtins/libm/ci/ci-util.py

@@ -63,9 +63,9 @@ MANY_EXTENSIVE_THRESHOLD = 20
 # Don't run exhaustive tests if these files change, even if they contaiin a function
 # definition.
 IGNORE_FILES = [
-    "src/math/support/",
-    "src/libm_helper.rs",
-    "src/math/arch/intrinsics.rs",
+    "libm/src/math/support/",
+    "libm/src/libm_helper.rs",
+    "libm/src/math/arch/intrinsics.rs",
 ]
 
 TYPES = ["f16", "f32", "f64", "f128"]

library/compiler-builtins/libm/crates/compiler-builtins-smoke-test/build.rs

@@ -1,8 +1,8 @@
-#[path = "../../configure.rs"]
+#[path = "../../libm/configure.rs"]
 mod configure;
 
 fn main() {
-    println!("cargo:rerun-if-changed=../../configure.rs");
+    println!("cargo:rerun-if-changed=../../libm/configure.rs");
     let cfg = configure::Config::from_env();
     configure::emit_libm_config(&cfg);
 }

library/compiler-builtins/libm/crates/compiler-builtins-smoke-test/src/math.rs

@@ -3,7 +3,7 @@ use core::ffi::c_int;
 #[allow(dead_code)]
 #[allow(clippy::all)] // We don't get `libm`'s list of `allow`s, so just ignore Clippy.
 #[allow(unused_imports)]
-#[path = "../../../src/math/mod.rs"]
+#[path = "../../../libm/src/math/mod.rs"]
 pub mod libm;
 
 /// Mark functions `#[no_mangle]` and with the C ABI.

library/compiler-builtins/libm/crates/libm-test/Cargo.toml

@@ -32,7 +32,7 @@ anyhow = "1.0.97"
 gmp-mpfr-sys = { version = "1.6.4", optional = true, default-features = false }
 iai-callgrind = { version = "0.14.0", optional = true }
 indicatif = { version = "0.17.11", default-features = false }
-libm = { path = "../..", features = ["unstable-public-internals"] }
+libm = { path = "../../libm", features = ["unstable-public-internals"] }
 libm-macros = { path = "../libm-macros" }
 musl-math-sys = { path = "../musl-math-sys", optional = true }
 paste = "1.0.15"

library/compiler-builtins/libm/crates/libm-test/build.rs

@@ -1,9 +1,9 @@
-#[path = "../../configure.rs"]
+#[path = "../../libm/configure.rs"]
 mod configure;
 use configure::Config;
 
 fn main() {
-    println!("cargo:rerun-if-changed=../../configure.rs");
+    println!("cargo:rerun-if-changed=../../libm/configure.rs");
     let cfg = Config::from_env();
     configure::emit_test_config(&cfg);
 }

library/compiler-builtins/libm/crates/musl-math-sys/Cargo.toml

@@ -7,7 +7,7 @@ publish = false
 [dependencies]
 
 [dev-dependencies]
-libm = { path = "../../" }
+libm = { path = "../../libm" }
 
 [build-dependencies]
 cc = "1.2.16"

library/compiler-builtins/libm/crates/util/Cargo.toml

@@ -11,7 +11,7 @@ build-mpfr = ["libm-test/build-mpfr", "dep:rug"]
 unstable-float = ["libm/unstable-float", "libm-test/unstable-float", "rug?/nightly-float"]
 
 [dependencies]
-libm = { path = "../..", default-features = false }
+libm = { path = "../../libm", default-features = false }
 libm-macros = { path = "../libm-macros" }
 libm-test = { path = "../libm-test", default-features = false }
 musl-math-sys = { path = "../musl-math-sys", optional = true }

library/compiler-builtins/libm/crates/util/build.rs

@@ -1,10 +1,10 @@
 #![allow(unexpected_cfgs)]
 
-#[path = "../../configure.rs"]
+#[path = "../../libm/configure.rs"]
 mod configure;
 
 fn main() {
-    println!("cargo:rerun-if-changed=../../configure.rs");
+    println!("cargo:rerun-if-changed=../../libm/configure.rs");
     let cfg = configure::Config::from_env();
     configure::emit_libm_config(&cfg);
 }

library/compiler-builtins/libm/etc/update-api-list.py

@@ -18,7 +18,7 @@ from typing import Any, Callable, TypeAlias
 
 SELF_PATH = Path(__file__)
 ETC_DIR = SELF_PATH.parent
-ROOT_DIR = ETC_DIR.parent
+LIBM_DIR = ETC_DIR.parent.joinpath("libm")
 
 # These files do not trigger a retest.
 IGNORED_SOURCES = ["src/libm_helper.rs", "src/math/support/float_traits.rs"]
@@ -75,7 +75,7 @@ class Crate:
                 "-Zunstable-options",
                 "-o-",
             ],
-            cwd=ROOT_DIR,
+            cwd=LIBM_DIR,
             text=True,
         )
         j = json.loads(j)
@@ -121,8 +121,8 @@ class Crate:
 
         # A lot of the `arch` module is often configured out so doesn't show up in docs. Use
         # string matching as a fallback.
-        for fname in glob("src/math/arch/**.rs", root_dir=ROOT_DIR):
-            contents = (ROOT_DIR.joinpath(fname)).read_text()
+        for fname in glob("src/math/arch/**.rs", root_dir=LIBM_DIR):
+            contents = (LIBM_DIR.joinpath(fname)).read_text()
 
             for name in self.public_functions:
                 if f"fn {name}" in contents:
@@ -188,10 +188,10 @@ class Crate:
         include all public API.
         """
 
-        flist = sp.check_output(["git", "ls-files"], cwd=ROOT_DIR, text=True)
+        flist = sp.check_output(["git", "ls-files"], cwd=LIBM_DIR, text=True)
 
         for path in flist.splitlines():
-            fpath = ROOT_DIR.joinpath(path)
+            fpath = LIBM_DIR.joinpath(path)
             if fpath.is_dir() or fpath == SELF_PATH:
                 continue
 
@@ -229,7 +229,7 @@ class Crate:
         if len(not_found) == 0:
             return
 
-        relpath = fpath.relative_to(ROOT_DIR)
+        relpath = fpath.relative_to(LIBM_DIR)
         eprint(f"functions not found at {relpath}:{line_num}: {not_found}")
         exit(1)
 
@@ -244,7 +244,7 @@ def validate_delimited_block(
     """Identify blocks of code wrapped within `start` and `end`, collect their contents
     to a list of strings, and call `validate` for each of those lists.
     """
-    relpath = fpath.relative_to(ROOT_DIR)
+    relpath = fpath.relative_to(LIBM_DIR)
     block_lines = []
     block_start_line: None | int = None
     for line_num, line in enumerate(lines):
@@ -274,7 +274,7 @@ def validate_delimited_block(
 
 def ensure_sorted(fpath: Path, block_start_line: int, lines: list[str]) -> None:
     """Ensure that a list of lines is sorted, otherwise print a diff and exit."""
-    relpath = fpath.relative_to(ROOT_DIR)
+    relpath = fpath.relative_to(LIBM_DIR)
     diff_and_exit(
         "\n".join(lines),
         "\n".join(sorted(lines)),

library/compiler-builtins/libm/libm/build.rs

@@ -6,6 +6,7 @@ fn main() {
     let cfg = configure::Config::from_env();
 
     println!("cargo:rerun-if-changed=build.rs");
+    println!("cargo:rerun-if-changed=configure.rs");
     println!("cargo:rustc-check-cfg=cfg(assert_no_panic)");
 
     // If set, enable `no-panic`. Requires LTO (`release-opt` profile).

library/compiler-builtins/libm/libm/src/math/copysignf.rs

@@ -0,0 +1,8 @@
+/// Sign of Y, magnitude of X (f32)
+///
+/// Constructs a number with the magnitude (absolute value) of its
+/// first argument, `x`, and the sign of its second argument, `y`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn copysignf(x: f32, y: f32) -> f32 {
+    super::generic::copysign(x, y)
+}

library/compiler-builtins/libm/libm/src/math/copysignf128.rs

@@ -0,0 +1,8 @@
+/// Sign of Y, magnitude of X (f128)
+///
+/// Constructs a number with the magnitude (absolute value) of its
+/// first argument, `x`, and the sign of its second argument, `y`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn copysignf128(x: f128, y: f128) -> f128 {
+    super::generic::copysign(x, y)
+}

library/compiler-builtins/libm/libm/src/math/copysignf16.rs

@@ -0,0 +1,8 @@
+/// Sign of Y, magnitude of X (f16)
+///
+/// Constructs a number with the magnitude (absolute value) of its
+/// first argument, `x`, and the sign of its second argument, `y`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn copysignf16(x: f16, y: f16) -> f16 {
+    super::generic::copysign(x, y)
+}

library/compiler-builtins/libm/libm/src/math/fabsf.rs

@@ -0,0 +1,39 @@
+/// Absolute value (magnitude) (f32)
+///
+/// Calculates the absolute value (magnitude) of the argument `x`,
+/// by direct manipulation of the bit representation of `x`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fabsf(x: f32) -> f32 {
+    select_implementation! {
+        name: fabsf,
+        use_arch: all(target_arch = "wasm32", intrinsics_enabled),
+        args: x,
+    }
+
+    super::generic::fabs(x)
+}
+
+// PowerPC tests are failing on LLVM 13: https://github.com/rust-lang/rust/issues/88520
+#[cfg(not(target_arch = "powerpc64"))]
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(fabsf(-1.0), 1.0);
+        assert_eq!(fabsf(2.8), 2.8);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/fabs
+    #[test]
+    fn spec_tests() {
+        assert!(fabsf(f32::NAN).is_nan());
+        for f in [0.0, -0.0].iter().copied() {
+            assert_eq!(fabsf(f), 0.0);
+        }
+        for f in [f32::INFINITY, f32::NEG_INFINITY].iter().copied() {
+            assert_eq!(fabsf(f), f32::INFINITY);
+        }
+    }
+}

library/compiler-builtins/libm/libm/src/math/fabsf128.rs

@@ -0,0 +1,31 @@
+/// Absolute value (magnitude) (f128)
+///
+/// Calculates the absolute value (magnitude) of the argument `x`,
+/// by direct manipulation of the bit representation of `x`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fabsf128(x: f128) -> f128 {
+    super::generic::fabs(x)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(fabsf128(-1.0), 1.0);
+        assert_eq!(fabsf128(2.8), 2.8);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/fabs
+    #[test]
+    fn spec_tests() {
+        assert!(fabsf128(f128::NAN).is_nan());
+        for f in [0.0, -0.0].iter().copied() {
+            assert_eq!(fabsf128(f), 0.0);
+        }
+        for f in [f128::INFINITY, f128::NEG_INFINITY].iter().copied() {
+            assert_eq!(fabsf128(f), f128::INFINITY);
+        }
+    }
+}

library/compiler-builtins/libm/libm/src/math/fabsf16.rs

@@ -0,0 +1,31 @@
+/// Absolute value (magnitude) (f16)
+///
+/// Calculates the absolute value (magnitude) of the argument `x`,
+/// by direct manipulation of the bit representation of `x`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fabsf16(x: f16) -> f16 {
+    super::generic::fabs(x)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(fabsf16(-1.0), 1.0);
+        assert_eq!(fabsf16(2.8), 2.8);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/fabs
+    #[test]
+    fn spec_tests() {
+        assert!(fabsf16(f16::NAN).is_nan());
+        for f in [0.0, -0.0].iter().copied() {
+            assert_eq!(fabsf16(f), 0.0);
+        }
+        for f in [f16::INFINITY, f16::NEG_INFINITY].iter().copied() {
+            assert_eq!(fabsf16(f), f16::INFINITY);
+        }
+    }
+}

library/compiler-builtins/libm/libm/src/math/fdimf.rs

@@ -0,0 +1,12 @@
+/// Positive difference (f32)
+///
+/// Determines the positive difference between arguments, returning:
+/// * x - y if x > y, or
+/// * +0    if x <= y, or
+/// * NAN   if either argument is NAN.
+///
+/// A range error may occur.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fdimf(x: f32, y: f32) -> f32 {
+    super::generic::fdim(x, y)
+}

library/compiler-builtins/libm/libm/src/math/fdimf128.rs

@@ -0,0 +1,12 @@
+/// Positive difference (f128)
+///
+/// Determines the positive difference between arguments, returning:
+/// * x - y if x > y, or
+/// * +0    if x <= y, or
+/// * NAN   if either argument is NAN.
+///
+/// A range error may occur.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fdimf128(x: f128, y: f128) -> f128 {
+    super::generic::fdim(x, y)
+}

library/compiler-builtins/libm/libm/src/math/fdimf16.rs

@@ -0,0 +1,12 @@
+/// Positive difference (f16)
+///
+/// Determines the positive difference between arguments, returning:
+/// * x - y if x > y, or
+/// * +0    if x <= y, or
+/// * NAN   if either argument is NAN.
+///
+/// A range error may occur.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fdimf16(x: f16, y: f16) -> f16 {
+    super::generic::fdim(x, y)
+}

library/compiler-builtins/libm/libm/src/math/floorf.rs

@@ -0,0 +1,13 @@
+/// Floor (f32)
+///
+/// Finds the nearest integer less than or equal to `x`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn floorf(x: f32) -> f32 {
+    select_implementation! {
+        name: floorf,
+        use_arch: all(target_arch = "wasm32", intrinsics_enabled),
+        args: x,
+    }
+
+    return super::generic::floor(x);
+}

library/compiler-builtins/libm/libm/src/math/floorf128.rs

@@ -0,0 +1,7 @@
+/// Floor (f128)
+///
+/// Finds the nearest integer less than or equal to `x`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn floorf128(x: f128) -> f128 {
+    return super::generic::floor(x);
+}

library/compiler-builtins/libm/libm/src/math/floorf16.rs

@@ -0,0 +1,7 @@
+/// Floor (f16)
+///
+/// Finds the nearest integer less than or equal to `x`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn floorf16(x: f16) -> f16 {
+    return super::generic::floor(x);
+}

library/compiler-builtins/libm/libm/src/math/fmodf.rs

@@ -0,0 +1,5 @@
+/// Calculate the remainder of `x / y`, the precise result of `x - trunc(x / y) * y`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fmodf(x: f32, y: f32) -> f32 {
+    super::generic::fmod(x, y)
+}

library/compiler-builtins/libm/libm/src/math/fmodf128.rs

@@ -0,0 +1,5 @@
+/// Calculate the remainder of `x / y`, the precise result of `x - trunc(x / y) * y`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fmodf128(x: f128, y: f128) -> f128 {
+    super::generic::fmod(x, y)
+}

library/compiler-builtins/libm/libm/src/math/fmodf16.rs

@@ -0,0 +1,5 @@
+/// Calculate the remainder of `x / y`, the precise result of `x - trunc(x / y) * y`.
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fmodf16(x: f16, y: f16) -> f16 {
+    super::generic::fmod(x, y)
+}