1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
// Configuration shared with both libm and libm-test
use std::env;
use std::path::PathBuf;
#[derive(Debug)]
#[allow(dead_code)]
pub struct Config {
pub manifest_dir: PathBuf,
pub out_dir: PathBuf,
pub opt_level: String,
pub cargo_features: Vec<String>,
pub target_triple: String,
pub target_arch: String,
pub target_env: String,
pub target_family: Option<String>,
pub target_os: String,
pub target_string: String,
pub target_vendor: String,
pub target_features: Vec<String>,
pub reliable_f128: bool,
pub reliable_f16: bool,
}
impl Config {
pub fn from_env() -> Self {
let target_triple = env::var("TARGET").unwrap();
let target_features = env::var("CARGO_CFG_TARGET_FEATURE")
.map(|feats| feats.split(',').map(ToOwned::to_owned).collect())
.unwrap_or_default();
let cargo_features = env::vars()
.filter_map(|(name, _value)| name.strip_prefix("CARGO_FEATURE_").map(ToOwned::to_owned))
.map(|s| s.to_lowercase().replace("_", "-"))
.collect();
Self {
target_triple,
manifest_dir: PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap()),
out_dir: PathBuf::from(env::var("OUT_DIR").unwrap()),
opt_level: env::var("OPT_LEVEL").unwrap(),
cargo_features,
target_arch: env::var("CARGO_CFG_TARGET_ARCH").unwrap(),
target_env: env::var("CARGO_CFG_TARGET_ENV").unwrap(),
target_family: env::var("CARGO_CFG_TARGET_FAMILY").ok(),
target_os: env::var("CARGO_CFG_TARGET_OS").unwrap(),
target_string: env::var("TARGET").unwrap(),
target_vendor: env::var("CARGO_CFG_TARGET_VENDOR").unwrap(),
target_features,
// Note that these are unstable options, so only show up with the nightly compiler or
// with `RUSTC_BOOTSTRAP=1` (which is required to use the types anyway).
reliable_f128: env::var_os("CARGO_CFG_TARGET_HAS_RELIABLE_F128").is_some(),
reliable_f16: env::var_os("CARGO_CFG_TARGET_HAS_RELIABLE_F16").is_some(),
}
}
}
/// Libm gets most config options made available.
#[allow(dead_code)]
pub fn emit_libm_config(cfg: &Config) {
emit_intrinsics_cfg();
emit_arch_cfg();
emit_optimization_cfg(cfg);
emit_cfg_shorthands(cfg);
emit_cfg_env(cfg);
emit_f16_f128_cfg(cfg);
}
/// Tests don't need most feature-related config.
#[allow(dead_code)]
pub fn emit_test_config(cfg: &Config) {
emit_optimization_cfg(cfg);
emit_cfg_shorthands(cfg);
emit_cfg_env(cfg);
emit_f16_f128_cfg(cfg);
}
/// Simplify the feature logic for enabling intrinsics so code only needs to use
/// `cfg(intrinsics_enabled)`.
fn emit_intrinsics_cfg() {
println!("cargo:rustc-check-cfg=cfg(intrinsics_enabled)");
// Disabled by default; `unstable-intrinsics` enables again; `force-soft-floats` overrides
// to disable.
if cfg!(feature = "unstable-intrinsics") && !cfg!(feature = "force-soft-floats") {
println!("cargo:rustc-cfg=intrinsics_enabled");
}
}
/// Simplify the feature logic for enabling arch-specific features so code only needs to use
/// `cfg(arch_enabled)`.
fn emit_arch_cfg() {
println!("cargo:rustc-check-cfg=cfg(arch_enabled)");
// Enabled by default via the "arch" feature, `force-soft-floats` overrides to disable.
if cfg!(feature = "arch") && !cfg!(feature = "force-soft-floats") {
println!("cargo:rustc-cfg=arch_enabled");
}
}
/// Some tests are extremely slow. Emit a config option based on optimization level.
fn emit_optimization_cfg(cfg: &Config) {
println!("cargo:rustc-check-cfg=cfg(optimizations_enabled)");
if !matches!(cfg.opt_level.as_str(), "0" | "1") {
println!("cargo:rustc-cfg=optimizations_enabled");
}
}
/// Provide an alias for common longer config combinations.
fn emit_cfg_shorthands(cfg: &Config) {
println!("cargo:rustc-check-cfg=cfg(x86_no_sse)");
if cfg.target_arch == "x86" && !cfg.target_features.iter().any(|f| f == "sse") {
// Shorthand to detect i586 targets
println!("cargo:rustc-cfg=x86_no_sse");
}
}
/// Reemit config that we make use of for test logging.
fn emit_cfg_env(cfg: &Config) {
println!(
"cargo:rustc-env=CFG_CARGO_FEATURES={:?}",
cfg.cargo_features
);
println!("cargo:rustc-env=CFG_OPT_LEVEL={}", cfg.opt_level);
println!(
"cargo:rustc-env=CFG_TARGET_FEATURES={:?}",
cfg.target_features
);
}
/// Configure whether or not `f16` and `f128` support should be enabled.
fn emit_f16_f128_cfg(cfg: &Config) {
println!("cargo:rustc-check-cfg=cfg(f16_enabled)");
println!("cargo:rustc-check-cfg=cfg(f128_enabled)");
// `unstable-float` enables these features.
if !cfg!(feature = "unstable-float") {
return;
}
/* See the compiler-builtins configure file for info about the meaning of these options */
// If the feature is set, disable both of these types.
let no_f16_f128 = cfg.cargo_features.iter().any(|s| s == "no-f16-f128");
println!("cargo:rustc-check-cfg=cfg(f16_enabled)");
if cfg.reliable_f16 && !no_f16_f128 {
println!("cargo:rustc-cfg=f16_enabled");
}
println!("cargo:rustc-check-cfg=cfg(f128_enabled)");
if cfg.reliable_f128 && !no_f16_f128 {
println!("cargo:rustc-cfg=f128_enabled");
}
}
|