bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Avoid unnecessary string interning for const_str

Browse source
This commit is contained in:
bjorn3 2022-06-28 17:34:24 +00:00
parent 94e93749ab
commit f6484fa9b5
8 changed files with 45 additions and 34 deletions
Download patch file Download diff file Expand all files Collapse all files

38
compiler/rustc_codegen_llvm/src/common.rs
View file

@ -14,7 +14,6 @@ use rustc_middle::bug;
use rustc_middle::mir::interpret::{ConstAllocation, GlobalAlloc, Scalar};
use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
use rustc_middle::ty::ScalarInt;
use rustc_span::symbol::Symbol;
use rustc_target::abi::{self, AddressSpace, HasDataLayout, Pointer, Size};
use libc::{c_char, c_uint};
@ -181,22 +180,27 @@ impl<'ll, 'tcx> ConstMethods<'tcx> for CodegenCx<'ll, 'tcx> {
unsafe { llvm::LLVMConstReal(t, val) }
}
fn const_str(&self, s: Symbol) -> (&'ll Value, &'ll Value) {
let s_str = s.as_str();
let str_global = *self.const_str_cache.borrow_mut().entry(s).or_insert_with(|| {
let sc = self.const_bytes(s_str.as_bytes());
let sym = self.generate_local_symbol_name("str");
let g = self.define_global(&sym, self.val_ty(sc)).unwrap_or_else(|| {
bug!("symbol `{}` is already defined", sym);
});
unsafe {
llvm::LLVMSetInitializer(g, sc);
llvm::LLVMSetGlobalConstant(g, True);
llvm::LLVMRustSetLinkage(g, llvm::Linkage::InternalLinkage);
}
g
});
let len = s_str.len();
fn const_str(&self, s: &str) -> (&'ll Value, &'ll Value) {
let str_global = *self
.const_str_cache
.borrow_mut()
.raw_entry_mut()
.from_key(s)
.or_insert_with(|| {
let sc = self.const_bytes(s.as_bytes());
let sym = self.generate_local_symbol_name("str");
let g = self.define_global(&sym, self.val_ty(sc)).unwrap_or_else(|| {
bug!("symbol `{}` is already defined", sym);
});
unsafe {
llvm::LLVMSetInitializer(g, sc);
llvm::LLVMSetGlobalConstant(g, True);
llvm::LLVMRustSetLinkage(g, llvm::Linkage::InternalLinkage);
}
(s.to_owned(), g)
})
.1;
let len = s.len();
let cs = consts::ptrcast(
str_global,
self.type_ptr_to(self.layout_of(self.tcx.types.str_).llvm_type(self)),

3
compiler/rustc_codegen_llvm/src/context.rs
View file

@ -26,7 +26,6 @@ use rustc_session::config::{BranchProtection, CFGuard, CFProtection};
use rustc_session::config::{CrateType, DebugInfo, PAuthKey, PacRet};
use rustc_session::Session;
use rustc_span::source_map::Span;
use rustc_span::symbol::Symbol;
use rustc_target::abi::{
call::FnAbi, HasDataLayout, PointeeInfo, Size, TargetDataLayout, VariantIdx,
};
@ -56,7 +55,7 @@ pub struct CodegenCx<'ll, 'tcx> {
pub vtables:
RefCell<FxHashMap<(Ty<'tcx>, Option<ty::PolyExistentialTraitRef<'tcx>>), &'ll Value>>,
/// Cache of constant strings,
pub const_str_cache: RefCell<FxHashMap<Symbol, &'ll Value>>,
pub const_str_cache: RefCell<FxHashMap<String, &'ll Value>>,
/// Reverse-direction for const ptrs cast from globals.
///

1
compiler/rustc_codegen_llvm/src/lib.rs
View file

@ -5,6 +5,7 @@
//! This API is completely unstable and subject to change.
#![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
#![feature(hash_raw_entry)]
#![feature(let_chains)]
#![feature(let_else)]
#![feature(extern_types)]