From 698f8c2f01ea549d77d7dc3338a12e04c11057b9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:02:58 +0200 Subject: Adding upstream version 1.64.0+dfsg1. Signed-off-by: Daniel Baumann --- vendor/memchr/build.rs | 88 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 vendor/memchr/build.rs (limited to 'vendor/memchr/build.rs') diff --git a/vendor/memchr/build.rs b/vendor/memchr/build.rs new file mode 100644 index 000000000..584a60856 --- /dev/null +++ b/vendor/memchr/build.rs @@ -0,0 +1,88 @@ +use std::env; + +fn main() { + enable_simd_optimizations(); + enable_libc(); +} + +// This adds various simd cfgs if this compiler and target support it. +// +// This can be disabled with RUSTFLAGS="--cfg memchr_disable_auto_simd", but +// this is generally only intended for testing. +// +// On targets which don't feature SSE2, this is disabled, as LLVM wouln't know +// how to work with SSE2 operands. Enabling SSE4.2 and AVX on SSE2-only targets +// is not a problem. In that case, the fastest option will be chosen at +// runtime. +fn enable_simd_optimizations() { + if is_env_set("CARGO_CFG_MEMCHR_DISABLE_AUTO_SIMD") { + return; + } + let arch = env::var("CARGO_CFG_TARGET_ARCH").unwrap(); + match &arch[..] { + "x86_64" => { + if !target_has_feature("sse2") { + return; + } + println!("cargo:rustc-cfg=memchr_runtime_simd"); + println!("cargo:rustc-cfg=memchr_runtime_sse2"); + println!("cargo:rustc-cfg=memchr_runtime_sse42"); + println!("cargo:rustc-cfg=memchr_runtime_avx"); + } + "wasm32" | "wasm64" => { + if !target_has_feature("simd128") { + return; + } + println!("cargo:rustc-cfg=memchr_runtime_simd"); + println!("cargo:rustc-cfg=memchr_runtime_wasm128"); + } + _ => {} + } +} + +// This adds a `memchr_libc` cfg if and only if libc can be used, if no other +// better option is available. +// +// This could be performed in the source code, but it's simpler to do it once +// here and consolidate it into one cfg knob. +// +// Basically, we use libc only if its enabled and if we aren't targeting a +// known bad platform. For example, wasm32 doesn't have a libc and the +// performance of memchr on Windows is seemingly worse than the fallback +// implementation. +fn enable_libc() { + const NO_ARCH: &'static [&'static str] = &["wasm32", "windows"]; + const NO_ENV: &'static [&'static str] = &["sgx"]; + + if !is_feature_set("LIBC") { + return; + } + + let arch = match env::var("CARGO_CFG_TARGET_ARCH") { + Err(_) => return, + Ok(arch) => arch, + }; + let env = match env::var("CARGO_CFG_TARGET_ENV") { + Err(_) => return, + Ok(env) => env, + }; + if NO_ARCH.contains(&&*arch) || NO_ENV.contains(&&*env) { + return; + } + + println!("cargo:rustc-cfg=memchr_libc"); +} + +fn is_feature_set(name: &str) -> bool { + is_env_set(&format!("CARGO_FEATURE_{}", name)) +} + +fn is_env_set(name: &str) -> bool { + env::var_os(name).is_some() +} + +fn target_has_feature(feature: &str) -> bool { + env::var("CARGO_CFG_TARGET_FEATURE") + .map(|features| features.contains(feature)) + .unwrap_or(false) +} -- cgit v1.2.3