Bug 1490948: Add support for extra bindgen flags when compiling Cranelift; r=froydnj

Some build flags are being passed by the build system: they're passed in a text
file called extra-bindgen-flags.in that's filled at configure time.

Other flags have to be inferred from the current target/host combination, in
Cranelift's build script directly. This is mostly cargo-culted from the
ServoBindings.toml file, and should probably be merged in the build system at
some point.

Some Windows-specific adjustments were needed to provide access to libclang for
bindgen support, by adding clang-cl to the plain Spidermonkey Windows builds.

--HG--
extra : rebase_source : 0bda40b1d1eb38c2657593f094c951013711d00a
extra : histedit_source : aad930a5f9099e299d385ae4de2deb81aed9b6d5

build/moz.configure/toolchain.configure

@@ -1116,10 +1116,10 @@ def check_have_64_bit(have_64_bit, compiler_have_64_bit):
                         'about the target bitness.')
 
 
-option(env='BINDGEN_CFLAGS',
-       nargs=1,
-       default=bindgen_cflags_defaults,
-       help='Options bindgen should pass to the C/C++ parser')
+js_option(env='BINDGEN_CFLAGS',
+          nargs=1,
+          default=bindgen_cflags_defaults,
+          help='Options bindgen should pass to the C/C++ parser')
 
 
 @depends('BINDGEN_CFLAGS')

js/src/old-configure.in

@@ -1820,6 +1820,9 @@ elif test "$EARLY_BETA_OR_EARLIER"; then
 fi
 AC_SUBST(EARLY_BETA_OR_EARLIER)
 
+BINDGEN_SYSTEM_FLAGS="$_BINDGEN_CFLAGS $NSPR_CFLAGS"
+AC_SUBST(BINDGEN_SYSTEM_FLAGS)
+
 dnl ========================================================
 dnl JavaScript shell
 dnl ========================================================

js/src/rust/extra-bindgen-flags.in

@@ -0,0 +1 @@
+@BINDGEN_SYSTEM_FLAGS@

js/src/rust/moz.build

@@ -6,6 +6,8 @@
 
 RustLibrary('jsrust')
 
+CONFIGURE_SUBST_FILES += ['extra-bindgen-flags']
+
 if CONFIG['JS_SHARED_LIBRARY']:
     FINAL_LIBRARY = 'js'
 

js/src/wasm/cranelift/build.rs

@@ -22,13 +22,22 @@
 extern crate bindgen;
 
 use std::env;
+use std::fs::File;
+use std::io::prelude::*;
 use std::path::PathBuf;
 
+enum Arch {
+    X86,
+    X64,
+    Arm,
+    Aarch64
+}
+
 fn main() {
     // Tell Cargo to regenerate the bindings if the header file changes.
     println!("cargo:rerun-if-changed=baldrapi.h");
 
-    let bindings = bindgen::builder()
+    let mut bindings = bindgen::builder()
         .disable_name_namespacing()
         // We whitelist the Baldr C functions and get the associated types for free.
         .whitelist_function("env_.*")
@@ -40,8 +49,79 @@ fn main() {
         .rustified_enum("BD_.*|Trap|TypeCode|FuncTypeIdDescKind")
         .whitelist_type("BD_.*|Trap|TypeCode|FuncTypeIdDescKind")
         .header("baldrapi.h")
-        .clang_args(&["-x", "c++", "-std=c++14"])
-        .clang_arg("-I../..")
+        .clang_args(&["-x", "c++", "-std=gnu++14", "-fno-sized-deallocation", "-DRUST_BINDGEN"])
+        .clang_arg("-I../..");
+
+    let arch = {
+        let target_arch = env::var("CARGO_CFG_TARGET_ARCH");
+        match target_arch.as_ref().map(|x| x.as_str()) {
+            Ok("aarch64") => Arch::Aarch64,
+            Ok("arm") => Arch::Arm,
+            Ok("x86") => Arch::X86,
+            Ok("x86_64") => Arch::X64,
+            _ => panic!("unknown arch")
+        }
+    };
+
+    match env::var("CARGO_CFG_TARGET_OS").as_ref().map(|x| x.as_str()) {
+        Ok("android") => {
+            bindings = bindings.clang_arg("-DOS_ANDROID=1");
+            bindings = match arch {
+                Arch::Aarch64 => { bindings.clang_arg("--target=aarch64-linux-android") }
+                Arch::Arm => { bindings.clang_arg("--target=armv7-linux-androideabi") }
+                Arch::X86 => { bindings.clang_arg("--target=i686-linux-android") }
+                Arch::X64 => { bindings.clang_arg("--target=x86_64-linux-android") }
+            };
+        }
+        Ok("linux") | Ok("freebsd") | Ok("dragonfly") | Ok("openbsd") | Ok("bitrig") | Ok("netbsd")
+            | Ok("macos") | Ok("ios") => {
+            // Nothing to do in particular for these OSes, until proven the contrary.
+        }
+        Ok("windows") => {
+            bindings = bindings.clang_arg("-DOS_WIN=1")
+                .clang_arg("-DWIN32=1");
+            bindings = match env::var("CARGO_CFG_TARGET_ENV").as_ref().map(|x| x.as_str()) {
+                Ok("msvc") => {
+                    bindings = bindings.clang_arg("-fms-compatibility-version=19");
+                    bindings = bindings.clang_arg("-D_CRT_USE_BUILTIN_OFFSETOF");
+                    bindings = bindings.clang_arg("-DHAVE_VISIBILITY_HIDDEN_ATTRIBUTE=1");
+                    match arch {
+                        Arch::X86 => { bindings.clang_arg("--target=i686-pc-win32") },
+                        Arch::X64 => { bindings.clang_arg("--target=x86_64-pc-win32") },
+                        Arch::Aarch64 => { bindings.clang_arg("--target=aarch64-pc-windows-msvc") }
+                        _ => panic!("unknown Windows architecture for msvc build")
+                    }
+                }
+                Ok("gnu") => {
+                    match arch {
+                        Arch::X86 => { bindings.clang_arg("--target=i686-pc-mingw32") },
+                        Arch::X64 => { bindings.clang_arg("--target=x86_64-w64-mingw32") },
+                        _ => panic!("unknown Windows architecture for gnu build")
+                    }
+                }
+                _ => panic!("unknown Windows build environment")
+            };
+        }
+        os => panic!("unknown target os {:?}!", os)
+    }
+
+    let path = PathBuf::from(env::var_os("MOZ_TOPOBJDIR").unwrap()).join("js/src/rust/extra-bindgen-flags");
+
+    let mut extra_flags = String::new();
+        File::open(&path)
+            .expect("Failed to open extra-bindgen-flags file")
+            .read_to_string(&mut extra_flags)
+            .expect("Failed to read extra-bindgen-flags file");
+
+    let display_path = path.to_str().expect("path is utf8 encoded");
+    println!("cargo:rerun-if-changed={}", display_path);
+
+    let extra_flags: Vec<String> = extra_flags.split_whitespace().map(|s| s.to_owned()).collect();
+    for flag in extra_flags {
+        bindings = bindings.clang_arg(flag);
+    }
+
+    let bindings = bindings
         .generate()
         .expect("Unable to generate baldrapi.h bindings");
 

layout/style/bindgen.toml.in

@@ -1,4 +1,4 @@
 [build]
 args = [
-    @BINDGEN_SYSTEM_FLAGS@
+    @BINDGEN_SYSTEM_TOML_FLAGS@
 ]

old-configure.in

@@ -3946,7 +3946,9 @@ AC_SUBST_LIST(MOZ_CAIRO_OSLIBS)
 AC_SUBST(MOZ_TREE_PIXMAN)
 
 BINDGEN_SYSTEM_FLAGS="$_BINDGEN_CFLAGS $NSPR_CFLAGS $NSS_CFLAGS $MOZ_PIXMAN_CFLAGS $MOZ_CAIRO_CFLAGS"
-AC_SUBST_TOML_LIST(BINDGEN_SYSTEM_FLAGS)
+AC_SUBST(BINDGEN_SYSTEM_FLAGS)
+BINDGEN_SYSTEM_TOML_FLAGS="$BINDGEN_SYSTEM_FLAGS"
+AC_SUBST_TOML_LIST(BINDGEN_SYSTEM_TOML_FLAGS)
 
 dnl ========================================================
 dnl disable xul

taskcluster/ci/spidermonkey/windows.yml

@@ -19,6 +19,7 @@ sm-plain-win32/debug:
     run:
         spidermonkey-variant: plaindebug
     toolchains:
+        - win64-clang-cl
         - win64-rust
 
 sm-plain-win32/opt:
@@ -31,6 +32,7 @@ sm-plain-win32/opt:
     run:
         spidermonkey-variant: plain
     toolchains:
+        - win64-clang-cl
         - win64-rust
 
 sm-compacting-win32/debug:
@@ -43,4 +45,5 @@ sm-compacting-win32/debug:
     run:
         spidermonkey-variant: compacting
     toolchains:
+        - win64-clang-cl
         - win64-rust