/// Whether or not stack probes (__rust_probestack) are enabled
pub stack_probes: bool,
+
+ /// The minimum alignment for global symbols.
+ pub min_global_align: Option<u64>,
}
impl Default for TargetOptions {
crt_static_default: false,
crt_static_respected: false,
stack_probes: false,
+ min_global_align: None,
}
}
}
key!(crt_static_default, bool);
key!(crt_static_respected, bool);
key!(stack_probes, bool);
+ key!(min_global_align, Option<u64>);
if let Some(array) = obj.find("abi-blacklist").and_then(Json::as_array) {
for name in array.iter().filter_map(|abi| abi.as_string()) {
target_option_val!(crt_static_default);
target_option_val!(crt_static_respected);
target_option_val!(stack_probes);
+ target_option_val!(min_global_align);
if default.abi_blacklist != self.options.abi_blacklist {
d.insert("abi-blacklist".to_string(), self.options.abi_blacklist.iter()
use rustc::hir;
+use std::cmp;
use std::ffi::{CStr, CString};
use syntax::ast;
use syntax::attr;
}
}
+fn set_global_alignment(ccx: &CrateContext,
+ gv: ValueRef,
+ mut align: machine::llalign) {
+ // The target may require greater alignment for globals than the type does.
+ // Note: GCC and Clang also allow `__attribute__((aligned))` on variables,
+ // which can force it to be smaller. Rust doesn't support this yet.
+ if let Some(min) = ccx.sess().target.target.options.min_global_align {
+ match ty::layout::Align::from_bits(min, min) {
+ Ok(min) => align = cmp::max(align, min.abi() as machine::llalign),
+ Err(err) => {
+ ccx.sess().err(&format!("invalid minimum global alignment: {}", err));
+ }
+ }
+ }
+ unsafe {
+ llvm::LLVMSetAlignment(gv, align);
+ }
+}
+
pub fn addr_of_mut(ccx: &CrateContext,
cv: ValueRef,
align: machine::llalign,
bug!("symbol `{}` is already defined", name);
});
llvm::LLVMSetInitializer(gv, cv);
- llvm::LLVMSetAlignment(gv, align);
+ set_global_alignment(ccx, gv, align);
llvm::LLVMRustSetLinkage(gv, llvm::Linkage::InternalLinkage);
SetUnnamedAddr(gv, true);
gv
ccx.statics_to_rauw().borrow_mut().push((g, new_g));
new_g
};
- llvm::LLVMSetAlignment(g, ccx.align_of(ty));
+ set_global_alignment(ccx, g, ccx.align_of(ty));
llvm::LLVMSetInitializer(g, v);
// As an optimization, all shared statics which do not have interior