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thestingerthestinger
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use element count in slices, not size in bytes
This allows the indexing bounds check or other comparisons against an element length to avoid a multiplication by the size.
1 parent aa93381 commit e1a26ad

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10 files changed

+154
-76
lines changed

10 files changed

+154
-76
lines changed

‎src/librustc/middle/trans/_match.rs

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1059,7 +1059,7 @@ fn extract_vec_elems(bcx: @mut Block,
10591059
Store(bcx, slice_begin,
10601060
GEPi(bcx, scratch.val, [0u, abi::slice_elt_base])
10611061
);
1062-
Store(bcx, slice_len,
1062+
Store(bcx, UDiv(bcx, slice_len, vt.llunit_size),
10631063
GEPi(bcx, scratch.val, [0u, abi::slice_elt_len])
10641064
);
10651065
elems[n] = scratch.val;

‎src/librustc/middle/trans/base.rs

Lines changed: 6 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -54,7 +54,7 @@ use middle::trans::glue;
5454
use middle::trans::inline;
5555
use middle::trans::llrepr::LlvmRepr;
5656
use middle::trans::machine;
57-
use middle::trans::machine::{llalign_of_min, llsize_of, llsize_of_alloc};
57+
use middle::trans::machine::{llalign_of_min, llsize_of};
5858
use middle::trans::meth;
5959
use middle::trans::monomorphize;
6060
use middle::trans::tvec;
@@ -2910,7 +2910,7 @@ pub fn decl_gc_metadata(ccx: &mut CrateContext, llmod_id: &str) {
29102910
}
29112911
}
29122912

2913-
pub fn create_module_map(ccx: &mut CrateContext) -> (ValueRef, uint, uint) {
2913+
pub fn create_module_map(ccx: &mut CrateContext) -> (ValueRef, uint) {
29142914
let str_slice_type = Type::struct_([Type::i8p(), ccx.int_type], false);
29152915
let elttype = Type::struct_([str_slice_type, ccx.int_type], false);
29162916
let maptype = Type::array(&elttype, ccx.module_data.len() as u64);
@@ -2942,7 +2942,7 @@ pub fn create_module_map(ccx: &mut CrateContext) -> (ValueRef, uint, uint) {
29422942
unsafe {
29432943
llvm::LLVMSetInitializer(map, C_array(elttype, elts));
29442944
}
2945-
return (map, keys.len(), llsize_of_alloc(ccx, elttype));
2945+
return (map, keys.len())
29462946
}
29472947

29482948

@@ -3004,19 +3004,17 @@ pub fn fill_crate_map(ccx: &mut CrateContext, map: ValueRef) {
30043004
lib::llvm::SetLinkage(vec_elements, lib::llvm::InternalLinkage);
30053005

30063006
llvm::LLVMSetInitializer(vec_elements, C_array(ccx.int_type, subcrates));
3007-
let (mod_map, mod_count, mod_struct_size) = create_module_map(ccx);
3007+
let (mod_map, mod_count) = create_module_map(ccx);
30083008

30093009
llvm::LLVMSetInitializer(map, C_struct(
30103010
[C_i32(2),
30113011
C_struct([
30123012
p2i(ccx, mod_map),
3013-
// byte size of the module map array, an entry consists of two integers
3014-
C_int(ccx, ((mod_count * mod_struct_size) as int))
3013+
C_uint(ccx, mod_count)
30153014
], false),
30163015
C_struct([
30173016
p2i(ccx, vec_elements),
3018-
// byte size of the subcrates array, an entry consists of an integer
3019-
C_int(ccx, (subcrates.len() * llsize_of_alloc(ccx, ccx.int_type)) as int)
3017+
C_uint(ccx, subcrates.len())
30203018
], false)
30213019
], false));
30223020
}

‎src/librustc/middle/trans/consts.rs

Lines changed: 18 additions & 30 deletions
Original file line numberDiff line numberDiff line change
@@ -83,23 +83,18 @@ pub fn const_ptrcast(cx: &mut CrateContext, a: ValueRef, t: Type) -> ValueRef {
8383
}
8484
}
8585

86-
pub fn const_vec(cx: @mut CrateContext, e: &ast::Expr, es: &[@ast::Expr])
87-
-> (ValueRef, ValueRef, Type, bool) {
88-
unsafe {
89-
let vec_ty = ty::expr_ty(cx.tcx, e);
90-
let unit_ty = ty::sequence_element_type(cx.tcx, vec_ty);
91-
let llunitty = type_of::type_of(cx, unit_ty);
92-
let unit_sz = machine::llsize_of(cx, llunitty);
93-
let sz = llvm::LLVMConstMul(C_uint(cx, es.len()), unit_sz);
94-
let (vs, inlineable) = vec::unzip(es.iter().map(|e| const_expr(cx, *e)));
95-
// If the vector contains enums, an LLVM array won't work.
96-
let v = if vs.iter().any(|vi| val_ty(*vi) != llunitty) {
97-
C_struct(vs, false)
98-
} else {
99-
C_array(llunitty, vs)
100-
};
101-
return (v, sz, llunitty, inlineable.iter().fold(true, |a, &b| a && b));
102-
}
86+
fn const_vec(cx: @mut CrateContext, e: &ast::Expr, es: &[@ast::Expr]) -> (ValueRef, Type, bool) {
87+
let vec_ty = ty::expr_ty(cx.tcx, e);
88+
let unit_ty = ty::sequence_element_type(cx.tcx, vec_ty);
89+
let llunitty = type_of::type_of(cx, unit_ty);
90+
let (vs, inlineable) = vec::unzip(es.iter().map(|e| const_expr(cx, *e)));
91+
// If the vector contains enums, an LLVM array won't work.
92+
let v = if vs.iter().any(|vi| val_ty(*vi) != llunitty) {
93+
C_struct(vs, false)
94+
} else {
95+
C_array(llunitty, vs)
96+
};
97+
(v, llunitty, inlineable.iter().fold(true, |a, &b| a && b))
10398
}
10499

105100
fn const_addr_of(cx: &mut CrateContext, cv: ValueRef) -> ValueRef {
@@ -225,9 +220,8 @@ pub fn const_expr(cx: @mut CrateContext, e: &ast::Expr) -> (ValueRef, bool) {
225220
assert_eq!(abi::slice_elt_len, 1);
226221

227222
match ty::get(ty).sty {
228-
ty::ty_evec(_, ty::vstore_fixed(*)) => {
229-
let size = machine::llsize_of(cx, val_ty(llconst));
230-
llconst = C_struct([llptr, size], false);
223+
ty::ty_evec(_, ty::vstore_fixed(len)) => {
224+
llconst = C_struct([llptr, C_uint(cx, len)], false);
231225
}
232226
_ => {}
233227
}
@@ -412,14 +406,8 @@ fn const_expr_unadjusted(cx: @mut CrateContext,
412406
(bv, C_uint(cx, u)),
413407

414408
ty::vstore_slice(_) => {
415-
let unit_ty = ty::sequence_element_type(cx.tcx, bt);
416-
let llunitty = type_of::type_of(cx, unit_ty);
417-
let unit_sz = machine::llsize_of(cx, llunitty);
418-
419409
let e1 = const_get_elt(cx, bv, [0]);
420-
(const_deref_ptr(cx, e1),
421-
llvm::LLVMConstUDiv(const_get_elt(cx, bv, [1]),
422-
unit_sz))
410+
(const_deref_ptr(cx, e1), const_get_elt(cx, bv, [1]))
423411
},
424412
_ => cx.sess.span_bug(base.span,
425413
"index-expr base must be fixed-size or slice")
@@ -538,7 +526,7 @@ fn const_expr_unadjusted(cx: @mut CrateContext,
538526
}
539527
}
540528
ast::ExprVec(ref es, ast::MutImmutable) => {
541-
let (v, _, _, inlineable) = const_vec(cx, e, *es);
529+
let (v, _, inlineable) = const_vec(cx, e, *es);
542530
(v, inlineable)
543531
}
544532
ast::ExprVstore(sub, ast::ExprVstoreSlice) => {
@@ -550,7 +538,7 @@ fn const_expr_unadjusted(cx: @mut CrateContext,
550538
}
551539
}
552540
ast::ExprVec(ref es, ast::MutImmutable) => {
553-
let (cv, sz, llunitty, _) = const_vec(cx, e, *es);
541+
let (cv, llunitty, _) = const_vec(cx, e, *es);
554542
let llty = val_ty(cv);
555543
let gv = do "const".with_c_str |name| {
556544
llvm::LLVMAddGlobal(cx.llmod, llty.to_ref(), name)
@@ -559,7 +547,7 @@ fn const_expr_unadjusted(cx: @mut CrateContext,
559547
llvm::LLVMSetGlobalConstant(gv, True);
560548
SetLinkage(gv, PrivateLinkage);
561549
let p = const_ptrcast(cx, gv, llunitty);
562-
(C_struct([p, sz], false), false)
550+
(C_struct([p, C_uint(cx, es.len())], false), false)
563551
}
564552
_ => cx.sess.span_bug(e.span, "bad const-slice expr")
565553
}

‎src/librustc/middle/trans/debuginfo.rs

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1865,7 +1865,7 @@ fn vec_slice_metadata(cx: &mut CrateContext,
18651865
offset: ComputedMemberOffset,
18661866
},
18671867
MemberDescription {
1868-
name: @"size_in_bytes",
1868+
name: @"length",
18691869
llvm_type: member_llvm_types[1],
18701870
type_metadata: type_metadata(cx, ty::mk_uint(), span),
18711871
offset: ComputedMemberOffset,

‎src/librustc/middle/trans/expr.rs

Lines changed: 5 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -274,8 +274,12 @@ pub fn trans_to_datum(bcx: @mut Block, expr: &ast::Expr) -> DatumBlock {
274274
ty::vstore_slice(ty::re_static));
275275

276276
let scratch = scratch_datum(bcx, slice_ty, "__adjust", false);
277+
278+
let vt = tvec::vec_types(bcx, datum.ty);
279+
let unscaled_len = UDiv(bcx, len, vt.llunit_size);
280+
277281
Store(bcx, base, GEPi(bcx, scratch.val, [0u, abi::slice_elt_base]));
278-
Store(bcx, len, GEPi(bcx, scratch.val, [0u, abi::slice_elt_len]));
282+
Store(bcx, unscaled_len, GEPi(bcx, scratch.val, [0u, abi::slice_elt_len]));
279283
DatumBlock {bcx: bcx, datum: scratch}
280284
}
281285

‎src/librustc/middle/trans/tvec.rs

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -237,8 +237,7 @@ pub fn trans_slice_vstore(bcx: @mut Block,
237237
Ignore => {}
238238
SaveIn(lldest) => {
239239
Store(bcx, llfixed, GEPi(bcx, lldest, [0u, abi::slice_elt_base]));
240-
let lllen = Mul(bcx, llcount, vt.llunit_size);
241-
Store(bcx, lllen, GEPi(bcx, lldest, [0u, abi::slice_elt_len]));
240+
Store(bcx, llcount, GEPi(bcx, lldest, [0u, abi::slice_elt_len]));
242241
}
243242
}
244243

@@ -529,7 +528,8 @@ pub fn get_base_and_len(bcx: @mut Block,
529528
}
530529
ty::vstore_slice(_) => {
531530
let base = Load(bcx, GEPi(bcx, llval, [0u, abi::slice_elt_base]));
532-
let len = Load(bcx, GEPi(bcx, llval, [0u, abi::slice_elt_len]));
531+
let count = Load(bcx, GEPi(bcx, llval, [0u, abi::slice_elt_len]));
532+
let len = Mul(bcx, count, vt.llunit_size);
533533
(base, len)
534534
}
535535
ty::vstore_uniq | ty::vstore_box => {

‎src/libstd/rand/mod.rs

Lines changed: 9 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -52,6 +52,8 @@ fn main () {
5252
```
5353
*/
5454

55+
use sys::size_of;
56+
use unstable::raw::Slice;
5557
use cast;
5658
use container::Container;
5759
use iter::{Iterator, range};
@@ -133,10 +135,10 @@ pub trait Rng {
133135
/// println!("{:?}", v);
134136
/// }
135137
/// ```
136-
fn fill_bytes(&mut self, mut dest: &mut [u8]) {
137-
// this relies on the lengths being transferred correctly when
138-
// transmuting between vectors like this.
139-
let as_u64: &mut &mut [u64] = unsafe { cast::transmute(&mut dest) };
138+
fn fill_bytes(&mut self, dest: &mut [u8]) {
139+
let mut slice: Slice<u64> = unsafe { cast::transmute_copy(&dest) };
140+
slice.len /= size_of::<u64>();
141+
let as_u64: &mut [u64] = unsafe { cast::transmute(slice) };
140142
for dest in as_u64.mut_iter() {
141143
*dest = self.next_u64();
142144
}
@@ -147,7 +149,9 @@ pub trait Rng {
147149

148150
// space for a u32
149151
if remaining >= 4 {
150-
let as_u32: &mut &mut [u32] = unsafe { cast::transmute(&mut dest) };
152+
let mut slice: Slice<u32> = unsafe { cast::transmute_copy(&dest) };
153+
slice.len /= size_of::<u32>();
154+
let as_u32: &mut [u32] = unsafe { cast::transmute(slice) };
151155
as_u32[as_u32.len() - 1] = self.next_u32();
152156
remaining -= 4;
153157
}

‎src/libstd/repr.rs

Lines changed: 19 additions & 16 deletions
Original file line numberDiff line numberDiff line change
@@ -186,12 +186,7 @@ impl<'self> ReprVisitor<'self> {
186186
}
187187
}
188188

189-
pub fn write_vec_range(&mut self,
190-
_mtbl: uint,
191-
ptr: *(),
192-
len: uint,
193-
inner: *TyDesc)
194-
-> bool {
189+
pub fn write_vec_range(&mut self, ptr: *(), len: uint, inner: *TyDesc) -> bool {
195190
let mut p = ptr as *u8;
196191
let (sz, al) = unsafe { ((*inner).size, (*inner).align) };
197192
self.writer.write(['[' as u8]);
@@ -213,13 +208,8 @@ impl<'self> ReprVisitor<'self> {
213208
true
214209
}
215210

216-
pub fn write_unboxed_vec_repr(&mut self,
217-
mtbl: uint,
218-
v: &raw::Vec<()>,
219-
inner: *TyDesc)
220-
-> bool {
221-
self.write_vec_range(mtbl, ptr::to_unsafe_ptr(&v.data),
222-
v.fill, inner)
211+
pub fn write_unboxed_vec_repr(&mut self, _: uint, v: &raw::Vec<()>, inner: *TyDesc) -> bool {
212+
self.write_vec_range(ptr::to_unsafe_ptr(&v.data), v.fill, inner)
223213
}
224214

225215
fn write_escaped_char(&mut self, ch: char, is_str: bool) {
@@ -377,19 +367,32 @@ impl<'self> TyVisitor for ReprVisitor<'self> {
377367
}
378368
}
379369

370+
#[cfg(stage0)]
380371
fn visit_evec_slice(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
381372
do self.get::<raw::Slice<()>> |this, s| {
382373
this.writer.write(['&' as u8]);
383374
this.write_mut_qualifier(mtbl);
384-
this.write_vec_range(mtbl, s.data, s.len, inner);
375+
this.write_vec_range(s.data, s.len, inner);
376+
}
377+
}
378+
379+
#[cfg(not(stage0))]
380+
fn visit_evec_slice(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
381+
do self.get::<raw::Slice<()>> |this, s| {
382+
this.writer.write(['&' as u8]);
383+
this.write_mut_qualifier(mtbl);
384+
let size = unsafe {
385+
if (*inner).size == 0 { 1 } else { (*inner).size }
386+
};
387+
this.write_vec_range(s.data, s.len * size, inner);
385388
}
386389
}
387390

388391
fn visit_evec_fixed(&mut self, n: uint, sz: uint, _align: uint,
389-
mtbl: uint, inner: *TyDesc) -> bool {
392+
_: uint, inner: *TyDesc) -> bool {
390393
let assumed_size = if sz == 0 { n } else { sz };
391394
do self.get::<()> |this, b| {
392-
this.write_vec_range(mtbl, ptr::to_unsafe_ptr(b), assumed_size, inner);
395+
this.write_vec_range(ptr::to_unsafe_ptr(b), assumed_size, inner);
393396
}
394397
}
395398

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