remove build script, bump MSRV to use standard cfg attributes for SIMD (#213)

Author: CathalMullan

.github/workflows/ci.yml

@@ -17,8 +17,7 @@ jobs:
       - simd
       - check_x86
       - aarch64
-      - msrv_x64
-      - msrv_aarch64
+      - msrv
       - miri
       - clippy_check
     steps:
@@ -44,7 +43,7 @@ jobs:
 
     runs-on: ${{ matrix.os }}
     env:
-      CARGO_CFG_HTTPARSE_DISABLE_SIMD: 1
+      RUSTFLAGS: --cfg httparse_disable_simd
 
     steps:
       - name: Checkout
@@ -76,14 +75,10 @@ jobs:
           - nightly
 
         target_feature:
+          - "" # runtime detection
           - "+sse4.2"
           - "+avx2"
           - "+sse4.2,+avx2"
-
-        disable_compiletime:
-          - 0
-          - 1
-
     steps:
       - name: Checkout
         uses: actions/checkout@v5
@@ -96,7 +91,6 @@ jobs:
       - name: Test
         env:
           RUSTFLAGS: -C target_feature=${{ matrix.target_feature }}
-          CARGO_CFG_HTTPARSE_DISABLE_SIMD_COMPILETIME: ${{ matrix.disable_compiletime }}
         run: cargo test
 
   check_x86:
@@ -113,48 +107,26 @@ jobs:
 
       - name: Test without SIMD
         env:
-          CARGO_CFG_HTTPARSE_DISABLE_SIMD_COMPILETIME: 1
+          RUSTFLAGS: --cfg httparse_disable_simd
         run: cargo test --target i686-unknown-linux-musl
 
       - name: Test
         run: cargo test --target i686-unknown-linux-musl
 
-  msrv_x64:
-    name: msrv (x64)
+  msrv:
+    name: msrv
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v5
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.47.0
+        uses: dtolnay/rust-toolchain@1.59.0
 
-      # Only build, dev-dependencies don't compile on 1.47.0
+      # Only build, dev-dependencies don't compile on 1.59.0
       - name: Build
         run: cargo build
 
-  # This tests that aarch64 gracefully fallbacks to SWAR if neon_intrinsics aren't available (<1.59)
-  msrv_aarch64:
-    name: msrv (aarch64)
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v5
-
-      - name: Install cross-compiling dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y gcc-aarch64-linux-gnu
-
-      - name: Setup Rust
-        uses: dtolnay/rust-toolchain@1.47.0
-        with:
-          target: aarch64-unknown-linux-gnu
-
-      # Only build, dev-dependencies don't compile on 1.47.0
-      - name: Build
-        run: cargo build --target aarch64-unknown-linux-gnu
-
   clippy_check:
     runs-on: ubuntu-latest
     steps:

.github/workflows/cibench.yml

@@ -5,12 +5,13 @@ on:
 
 env:
   CARGO_TERM_COLOR: always
-  RUSTFLAGS: "-C target-cpu=native"
 
 jobs:
   benchmark:
     name: Run benchmarks
     runs-on: ubuntu-latest
+    env:
+      RUSTFLAGS: "-C target-cpu=native"
     steps:
       - uses: actions/checkout@v5
         with:
@@ -41,7 +42,17 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        feature: [swar, sse42, avx2]
+        include:
+          - feature: runtime
+            rustflags: ""
+          - feature: swar
+            rustflags: "--cfg httparse_disable_simd"
+          - feature: sse4.2
+            rustflags: "-C target-feature=+sse4.2"
+          - feature: avx2
+            rustflags: "-C target-feature=+avx2"
+    env:
+      RUSTFLAGS: ${{ matrix.rustflags }}
     steps:
       - uses: actions/checkout@v5
         with:
@@ -57,17 +68,11 @@ jobs:
         run: |
           git checkout master
           cargo bench --bench parse -- --save-baseline master-${{ matrix.feature }}
-        env:
-          CARGO_CFG_HTTPARSE_DISABLE_SIMD: ${{ matrix.feature == 'swar' && '1' || '0' }}
-          RUSTFLAGS: ${{ matrix.feature != 'swar' && format('-C target-feature=+{0}', matrix.feature) || '' }}
 
       - name: Run benchmarks (PR)
         run: |
           git checkout ${{ github.event.pull_request.head.sha }}
           cargo bench --bench parse -- --save-baseline pr-${{ github.event.pull_request.number }}-${{ github.event.pull_request.head.sha }}-${{ matrix.feature }}
-        env:
-          CARGO_CFG_HTTPARSE_DISABLE_SIMD: ${{ matrix.feature == 'swar' && '1' || '0' }}
-          RUSTFLAGS: ${{ matrix.feature != 'swar' && format('-C target-feature=+{0}', matrix.feature) || '' }}
 
       - name: Compare benchmarks
         run: |
@@ -78,7 +83,13 @@ jobs:
     runs-on: macos-latest
     strategy:
       matrix:
-        feature: [swar, neon]
+        include:
+          - feature: swar
+            rustflags: "--cfg httparse_disable_simd"
+          - feature: neon
+            rustflags: "-C target-feature=+neon"
+    env:
+      RUSTFLAGS: ${{ matrix.rustflags }}
     steps:
       - uses: actions/checkout@v5
         with:
@@ -94,17 +105,11 @@ jobs:
         run: |
           git checkout master
           cargo bench --bench parse -- --save-baseline master-aarch64-${{ matrix.feature }}
-        env:
-          CARGO_CFG_HTTPARSE_DISABLE_SIMD: ${{ matrix.feature == 'swar' && '1' || '0' }}
-          RUSTFLAGS: ${{ matrix.feature == 'neon' && '-C target-feature=+neon' || '' }}
 
       - name: Run benchmarks (PR)
         run: |
           git checkout ${{ github.event.pull_request.head.sha }}
           cargo bench --bench parse -- --save-baseline pr-${{ github.event.pull_request.number }}-${{ github.event.pull_request.head.sha }}-aarch64-${{ matrix.feature }}
-        env:
-          CARGO_CFG_HTTPARSE_DISABLE_SIMD: ${{ matrix.feature == 'swar' && '1' || '0' }}
-          RUSTFLAGS: ${{ matrix.feature == 'neon' && '-C target-feature=+neon' || '' }}
 
       - name: Compare benchmarks
         run: |

Cargo.toml

@@ -9,8 +9,8 @@ documentation = "https://docs.rs/httparse"
 readme = "README.md"
 keywords = ["http", "parser", "no_std"]
 categories = ["network-programming", "no-std", "parser-implementations", "web-programming"]
-edition = "2018"
-build = "build.rs"
+edition = "2021"
+rust-version = "1.59"
 
 [features]
 default = ["std"]
@@ -34,8 +34,5 @@ opt-level = 3
 
 [lints.rust]
 unexpected_cfgs = { level = "warn", check-cfg = [
-    'cfg(httparse_simd)',
-    'cfg(httparse_simd_target_feature_avx2)',
-    'cfg(httparse_simd_target_feature_sse42)',
-    'cfg(httparse_simd_neon_intrinsics)',
+    'cfg(httparse_disable_simd)',
 ] }

build.rs

@@ -10,10 +10,10 @@ macro_rules! next {
 }
 
 macro_rules! expect {
-    ($bytes:ident.next() == $pat:pat => $ret:expr) => {
+    ($bytes:ident.next() == $pat:pat_param => $ret:expr) => {
         expect!(next!($bytes) => $pat |? $ret)
     };
-    ($e:expr => $pat:pat |? $ret:expr) => {
+    ($e:expr => $pat:pat_param |? $ret:expr) => {
         match $e {
             v@$pat => v,
             _ => return $ret
@@ -31,7 +31,7 @@ macro_rules! complete {
 }
 
 macro_rules! byte_map {
-    ($($p:pat)|+) => {{
+    ($($p:pat_param)|+) => {{
         const fn make_map() -> [bool; 256] {
             let mut ret = [false; 256];
             let mut i = 0;