OpenE2K/rust
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

librustc: Stop generating first-class aggregates in visit glue, since they kick us off fast isel. Closes #4352. rs=minor-perf-improvement

Browse Source
This commit is contained in:
Patrick Walton 2013-01-04 23:06:25 -08:00
parent 9abcacc0f3
commit 7b245d46ed
2 changed files with 13 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/librustc/middle/trans/common.rs
View File

@ -1094,6 +1094,8 @@ fn C_cstr(cx: @crate_ctxt, s: ~str) -> ValueRef {
return g;
}
// NB: Do not use `do_spill_noroot` to make this into a constant string, or
// you will be kicked off fast isel. See issue #4352 for an example of this.
fn C_estr_slice(cx: @crate_ctxt, s: ~str) -> ValueRef {
let cs = llvm::LLVMConstPointerCast(C_cstr(cx, s), T_ptr(T_i8()));
C_struct(~[cs, C_uint(cx, str::len(s) + 1u /* +1 for null */)])

13
src/librustc/middle/trans/reflect.rs
View File

@ -46,8 +46,17 @@ impl reflector {
}
fn c_slice(s: ~str) -> ValueRef {
let ss = C_estr_slice(self.bcx.ccx(), s);
do_spill_noroot(self.bcx, ss)
// We're careful to not use first class aggregates here because that
// will kick us off fast isel. (Issue #4352.)
let bcx = self.bcx;
let str_vstore = ty::vstore_slice(ty::re_static);
let str_ty = ty::mk_estr(bcx.tcx(), str_vstore);
let scratch = scratch_datum(bcx, str_ty, false);
let c_str = PointerCast(bcx, C_cstr(bcx.ccx(), s), T_ptr(T_i8()));
Store(bcx, c_str, GEPi(bcx, scratch.val, [ 0, 0 ]));
let len = C_uint(bcx.ccx(), s.len() + 1);
Store(bcx, len, GEPi(bcx, scratch.val, [ 0, 1 ]));
scratch.val
}
fn c_size_and_align(t: ty::t) -> ~[ValueRef] {