| // Copyright 2012 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| |
| use back::abi; |
| use llvm; |
| use llvm::{ConstFCmp, ConstICmp, SetLinkage, PrivateLinkage, ValueRef, Bool, True, False}; |
| use llvm::{IntEQ, IntNE, IntUGT, IntUGE, IntULT, IntULE, IntSGT, IntSGE, IntSLT, IntSLE, |
| RealOEQ, RealOGT, RealOGE, RealOLT, RealOLE, RealONE}; |
| use metadata::csearch; |
| use middle::const_eval; |
| use middle::def; |
| use middle::trans::adt; |
| use middle::trans::base; |
| use middle::trans::base::push_ctxt; |
| use middle::trans::closure; |
| use middle::trans::common::*; |
| use middle::trans::consts; |
| use middle::trans::expr; |
| use middle::trans::inline; |
| use middle::trans::machine; |
| use middle::trans::type_::Type; |
| use middle::trans::type_of; |
| use middle::trans::debuginfo; |
| use middle::ty; |
| use util::ppaux::{Repr, ty_to_string}; |
| |
| use std::c_str::ToCStr; |
| use libc::c_uint; |
| use syntax::{ast, ast_util}; |
| use syntax::ptr::P; |
| |
| pub fn const_lit(cx: &CrateContext, e: &ast::Expr, lit: &ast::Lit) |
| -> ValueRef { |
| let _icx = push_ctxt("trans_lit"); |
| debug!("const_lit: {}", lit); |
| match lit.node { |
| ast::LitByte(b) => C_integral(Type::uint_from_ty(cx, ast::TyU8), b as u64, false), |
| ast::LitChar(i) => C_integral(Type::char(cx), i as u64, false), |
| ast::LitInt(i, ast::SignedIntLit(t, _)) => { |
| C_integral(Type::int_from_ty(cx, t), i, true) |
| } |
| ast::LitInt(u, ast::UnsignedIntLit(t)) => { |
| C_integral(Type::uint_from_ty(cx, t), u, false) |
| } |
| ast::LitInt(i, ast::UnsuffixedIntLit(_)) => { |
| let lit_int_ty = ty::node_id_to_type(cx.tcx(), e.id); |
| match ty::get(lit_int_ty).sty { |
| ty::ty_int(t) => { |
| C_integral(Type::int_from_ty(cx, t), i as u64, true) |
| } |
| ty::ty_uint(t) => { |
| C_integral(Type::uint_from_ty(cx, t), i as u64, false) |
| } |
| _ => cx.sess().span_bug(lit.span, |
| format!("integer literal has type {} (expected int \ |
| or uint)", |
| ty_to_string(cx.tcx(), lit_int_ty)).as_slice()) |
| } |
| } |
| ast::LitFloat(ref fs, t) => { |
| C_floating(fs.get(), Type::float_from_ty(cx, t)) |
| } |
| ast::LitFloatUnsuffixed(ref fs) => { |
| let lit_float_ty = ty::node_id_to_type(cx.tcx(), e.id); |
| match ty::get(lit_float_ty).sty { |
| ty::ty_float(t) => { |
| C_floating(fs.get(), Type::float_from_ty(cx, t)) |
| } |
| _ => { |
| cx.sess().span_bug(lit.span, |
| "floating point literal doesn't have the right type"); |
| } |
| } |
| } |
| ast::LitBool(b) => C_bool(cx, b), |
| ast::LitNil => C_nil(cx), |
| ast::LitStr(ref s, _) => C_str_slice(cx, (*s).clone()), |
| ast::LitBinary(ref data) => C_binary_slice(cx, data.as_slice()), |
| } |
| } |
| |
| pub fn const_ptrcast(cx: &CrateContext, a: ValueRef, t: Type) -> ValueRef { |
| unsafe { |
| let b = llvm::LLVMConstPointerCast(a, t.ptr_to().to_ref()); |
| assert!(cx.const_globals().borrow_mut().insert(b as int, a).is_none()); |
| b |
| } |
| } |
| |
| fn const_vec(cx: &CrateContext, e: &ast::Expr, |
| es: &[P<ast::Expr>]) -> (ValueRef, Type) { |
| let vec_ty = ty::expr_ty(cx.tcx(), e); |
| let unit_ty = ty::sequence_element_type(cx.tcx(), vec_ty); |
| let llunitty = type_of::type_of(cx, unit_ty); |
| let vs = es.iter().map(|e| const_expr(cx, &**e).val0()) |
| .collect::<Vec<_>>(); |
| // If the vector contains enums, an LLVM array won't work. |
| let v = if vs.iter().any(|vi| val_ty(*vi) != llunitty) { |
| C_struct(cx, vs.as_slice(), false) |
| } else { |
| C_array(llunitty, vs.as_slice()) |
| }; |
| (v, llunitty) |
| } |
| |
| pub fn const_addr_of(cx: &CrateContext, cv: ValueRef, mutbl: ast::Mutability) -> ValueRef { |
| unsafe { |
| let gv = "const".with_c_str(|name| { |
| llvm::LLVMAddGlobal(cx.llmod(), val_ty(cv).to_ref(), name) |
| }); |
| llvm::LLVMSetInitializer(gv, cv); |
| llvm::LLVMSetGlobalConstant(gv, |
| if mutbl == ast::MutImmutable {True} else {False}); |
| SetLinkage(gv, PrivateLinkage); |
| gv |
| } |
| } |
| |
| fn const_deref_ptr(cx: &CrateContext, v: ValueRef) -> ValueRef { |
| let v = match cx.const_globals().borrow().get(&(v as int)) { |
| Some(&v) => v, |
| None => v |
| }; |
| unsafe { |
| llvm::LLVMGetInitializer(v) |
| } |
| } |
| |
| fn const_deref_newtype(cx: &CrateContext, v: ValueRef, t: ty::t) |
| -> ValueRef { |
| let repr = adt::represent_type(cx, t); |
| adt::const_get_field(cx, &*repr, v, 0, 0) |
| } |
| |
| fn const_deref(cx: &CrateContext, v: ValueRef, t: ty::t, explicit: bool) |
| -> (ValueRef, ty::t) { |
| match ty::deref(t, explicit) { |
| Some(ref mt) => { |
| match ty::get(t).sty { |
| ty::ty_ptr(mt) | ty::ty_rptr(_, mt) => { |
| if ty::type_is_sized(cx.tcx(), mt.ty) { |
| (const_deref_ptr(cx, v), mt.ty) |
| } else { |
| // Derefing a fat pointer does not change the representation, |
| // just the type to ty_open. |
| (v, ty::mk_open(cx.tcx(), mt.ty)) |
| } |
| } |
| ty::ty_enum(..) | ty::ty_struct(..) => { |
| assert!(mt.mutbl != ast::MutMutable); |
| (const_deref_newtype(cx, v, t), mt.ty) |
| } |
| _ => { |
| cx.sess().bug(format!("unexpected dereferenceable type {}", |
| ty_to_string(cx.tcx(), t)).as_slice()) |
| } |
| } |
| } |
| None => { |
| cx.sess().bug(format!("cannot dereference const of type {}", |
| ty_to_string(cx.tcx(), t)).as_slice()) |
| } |
| } |
| } |
| |
| pub fn get_const_val(cx: &CrateContext, |
| mut def_id: ast::DefId) -> ValueRef { |
| let contains_key = cx.const_values().borrow().contains_key(&def_id.node); |
| if !ast_util::is_local(def_id) || !contains_key { |
| if !ast_util::is_local(def_id) { |
| def_id = inline::maybe_instantiate_inline(cx, def_id); |
| } |
| |
| match cx.tcx().map.expect_item(def_id.node).node { |
| ast::ItemConst(..) => { base::get_item_val(cx, def_id.node); } |
| _ => {} |
| } |
| } |
| |
| cx.const_values().borrow().get_copy(&def_id.node) |
| } |
| |
| pub fn const_expr(cx: &CrateContext, e: &ast::Expr) -> (ValueRef, ty::t) { |
| let llconst = const_expr_unadjusted(cx, e); |
| let mut llconst = llconst; |
| let ety = ty::expr_ty(cx.tcx(), e); |
| let mut ety_adjusted = ty::expr_ty_adjusted(cx.tcx(), e); |
| let opt_adj = cx.tcx().adjustments.borrow().find_copy(&e.id); |
| match opt_adj { |
| None => { } |
| Some(adj) => { |
| match adj { |
| ty::AdjustAddEnv(ty::RegionTraitStore(ty::ReStatic, _)) => { |
| let def = ty::resolve_expr(cx.tcx(), e); |
| let wrapper = closure::get_wrapper_for_bare_fn(cx, |
| ety_adjusted, |
| def, |
| llconst, |
| true); |
| llconst = C_struct(cx, [wrapper, C_null(Type::i8p(cx))], false) |
| } |
| ty::AdjustAddEnv(store) => { |
| cx.sess() |
| .span_bug(e.span, |
| format!("unexpected static function: {}", |
| store).as_slice()) |
| } |
| ty::AdjustDerefRef(ref adj) => { |
| let mut ty = ety; |
| // Save the last autoderef in case we can avoid it. |
| if adj.autoderefs > 0 { |
| for _ in range(0, adj.autoderefs-1) { |
| let (dv, dt) = const_deref(cx, llconst, ty, false); |
| llconst = dv; |
| ty = dt; |
| } |
| } |
| |
| match adj.autoref { |
| None => { |
| let (dv, dt) = const_deref(cx, llconst, ty, false); |
| llconst = dv; |
| |
| // If we derefed a fat pointer then we will have an |
| // open type here. So we need to update the type with |
| // the one returned from const_deref. |
| ety_adjusted = dt; |
| } |
| Some(ref autoref) => { |
| match *autoref { |
| ty::AutoUnsafe(_, None) | |
| ty::AutoPtr(ty::ReStatic, _, None) => { |
| // Don't copy data to do a deref+ref |
| // (i.e., skip the last auto-deref). |
| if adj.autoderefs == 0 { |
| llconst = const_addr_of(cx, llconst, ast::MutImmutable); |
| } |
| } |
| ty::AutoPtr(ty::ReStatic, _, Some(box ty::AutoUnsize(..))) => { |
| if adj.autoderefs > 0 { |
| // Seeing as we are deref'ing here and take a reference |
| // again to make the pointer part of the far pointer below, |
| // we just skip the whole thing. We still need the type |
| // though. This works even if we don't need to deref |
| // because of byref semantics. Note that this is not just |
| // an optimisation, it is necessary for mutable vectors to |
| // work properly. |
| let (_, dt) = const_deref(cx, llconst, ty, false); |
| ty = dt; |
| } else { |
| llconst = const_addr_of(cx, llconst, ast::MutImmutable) |
| } |
| |
| match ty::get(ty).sty { |
| ty::ty_vec(unit_ty, Some(len)) => { |
| let llunitty = type_of::type_of(cx, unit_ty); |
| let llptr = const_ptrcast(cx, llconst, llunitty); |
| assert_eq!(abi::slice_elt_base, 0); |
| assert_eq!(abi::slice_elt_len, 1); |
| llconst = C_struct(cx, [ |
| llptr, |
| C_uint(cx, len) |
| ], false); |
| } |
| _ => cx.sess().span_bug(e.span, |
| format!("unimplemented type in const unsize: {}", |
| ty_to_string(cx.tcx(), ty)).as_slice()) |
| } |
| } |
| _ => { |
| cx.sess() |
| .span_bug(e.span, |
| format!("unimplemented const \ |
| autoref {}", |
| autoref).as_slice()) |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| let llty = type_of::sizing_type_of(cx, ety_adjusted); |
| let csize = machine::llsize_of_alloc(cx, val_ty(llconst)); |
| let tsize = machine::llsize_of_alloc(cx, llty); |
| if csize != tsize { |
| unsafe { |
| // FIXME these values could use some context |
| llvm::LLVMDumpValue(llconst); |
| llvm::LLVMDumpValue(C_undef(llty)); |
| } |
| cx.sess().bug(format!("const {} of type {} has size {} instead of {}", |
| e.repr(cx.tcx()), ty_to_string(cx.tcx(), ety), |
| csize, tsize).as_slice()); |
| } |
| (llconst, ety_adjusted) |
| } |
| |
| // the bool returned is whether this expression can be inlined into other crates |
| // if it's assigned to a static. |
| fn const_expr_unadjusted(cx: &CrateContext, e: &ast::Expr) -> ValueRef { |
| let map_list = |exprs: &[P<ast::Expr>]| { |
| exprs.iter().map(|e| const_expr(cx, &**e).val0()) |
| .fold(Vec::new(), |mut l, val| { l.push(val); l }) |
| }; |
| unsafe { |
| let _icx = push_ctxt("const_expr"); |
| return match e.node { |
| ast::ExprLit(ref lit) => { |
| consts::const_lit(cx, e, &**lit) |
| } |
| ast::ExprBinary(b, ref e1, ref e2) => { |
| let (te1, _) = const_expr(cx, &**e1); |
| let (te2, _) = const_expr(cx, &**e2); |
| |
| let te2 = base::cast_shift_const_rhs(b, te1, te2); |
| |
| /* Neither type is bottom, and we expect them to be unified |
| * already, so the following is safe. */ |
| let ty = ty::expr_ty(cx.tcx(), &**e1); |
| let is_float = ty::type_is_fp(ty); |
| let signed = ty::type_is_signed(ty); |
| return match b { |
| ast::BiAdd => { |
| if is_float { llvm::LLVMConstFAdd(te1, te2) } |
| else { llvm::LLVMConstAdd(te1, te2) } |
| } |
| ast::BiSub => { |
| if is_float { llvm::LLVMConstFSub(te1, te2) } |
| else { llvm::LLVMConstSub(te1, te2) } |
| } |
| ast::BiMul => { |
| if is_float { llvm::LLVMConstFMul(te1, te2) } |
| else { llvm::LLVMConstMul(te1, te2) } |
| } |
| ast::BiDiv => { |
| if is_float { llvm::LLVMConstFDiv(te1, te2) } |
| else if signed { llvm::LLVMConstSDiv(te1, te2) } |
| else { llvm::LLVMConstUDiv(te1, te2) } |
| } |
| ast::BiRem => { |
| if is_float { llvm::LLVMConstFRem(te1, te2) } |
| else if signed { llvm::LLVMConstSRem(te1, te2) } |
| else { llvm::LLVMConstURem(te1, te2) } |
| } |
| ast::BiAnd => llvm::LLVMConstAnd(te1, te2), |
| ast::BiOr => llvm::LLVMConstOr(te1, te2), |
| ast::BiBitXor => llvm::LLVMConstXor(te1, te2), |
| ast::BiBitAnd => llvm::LLVMConstAnd(te1, te2), |
| ast::BiBitOr => llvm::LLVMConstOr(te1, te2), |
| ast::BiShl => llvm::LLVMConstShl(te1, te2), |
| ast::BiShr => { |
| if signed { llvm::LLVMConstAShr(te1, te2) } |
| else { llvm::LLVMConstLShr(te1, te2) } |
| } |
| ast::BiEq => { |
| if is_float { ConstFCmp(RealOEQ, te1, te2) } |
| else { ConstICmp(IntEQ, te1, te2) } |
| }, |
| ast::BiLt => { |
| if is_float { ConstFCmp(RealOLT, te1, te2) } |
| else { |
| if signed { ConstICmp(IntSLT, te1, te2) } |
| else { ConstICmp(IntULT, te1, te2) } |
| } |
| }, |
| ast::BiLe => { |
| if is_float { ConstFCmp(RealOLE, te1, te2) } |
| else { |
| if signed { ConstICmp(IntSLE, te1, te2) } |
| else { ConstICmp(IntULE, te1, te2) } |
| } |
| }, |
| ast::BiNe => { |
| if is_float { ConstFCmp(RealONE, te1, te2) } |
| else { ConstICmp(IntNE, te1, te2) } |
| }, |
| ast::BiGe => { |
| if is_float { ConstFCmp(RealOGE, te1, te2) } |
| else { |
| if signed { ConstICmp(IntSGE, te1, te2) } |
| else { ConstICmp(IntUGE, te1, te2) } |
| } |
| }, |
| ast::BiGt => { |
| if is_float { ConstFCmp(RealOGT, te1, te2) } |
| else { |
| if signed { ConstICmp(IntSGT, te1, te2) } |
| else { ConstICmp(IntUGT, te1, te2) } |
| } |
| }, |
| } |
| }, |
| ast::ExprUnary(u, ref e) => { |
| let (te, _) = const_expr(cx, &**e); |
| let ty = ty::expr_ty(cx.tcx(), &**e); |
| let is_float = ty::type_is_fp(ty); |
| return match u { |
| ast::UnUniq | ast::UnDeref => { |
| let (dv, _dt) = const_deref(cx, te, ty, true); |
| dv |
| } |
| ast::UnNot => llvm::LLVMConstNot(te), |
| ast::UnNeg => { |
| if is_float { llvm::LLVMConstFNeg(te) } |
| else { llvm::LLVMConstNeg(te) } |
| } |
| } |
| } |
| ast::ExprField(ref base, field, _) => { |
| let (bv, bt) = const_expr(cx, &**base); |
| let brepr = adt::represent_type(cx, bt); |
| expr::with_field_tys(cx.tcx(), bt, None, |discr, field_tys| { |
| let ix = ty::field_idx_strict(cx.tcx(), field.node.name, field_tys); |
| adt::const_get_field(cx, &*brepr, bv, discr, ix) |
| }) |
| } |
| ast::ExprTupField(ref base, idx, _) => { |
| let (bv, bt) = const_expr(cx, &**base); |
| let brepr = adt::represent_type(cx, bt); |
| expr::with_field_tys(cx.tcx(), bt, None, |discr, _| { |
| adt::const_get_field(cx, &*brepr, bv, discr, idx.node) |
| }) |
| } |
| |
| ast::ExprIndex(ref base, ref index) => { |
| let (bv, bt) = const_expr(cx, &**base); |
| let iv = match const_eval::eval_const_expr(cx.tcx(), &**index) { |
| const_eval::const_int(i) => i as u64, |
| const_eval::const_uint(u) => u, |
| _ => cx.sess().span_bug(index.span, |
| "index is not an integer-constant expression") |
| }; |
| let (arr, len) = match ty::get(bt).sty { |
| ty::ty_vec(_, Some(u)) => (bv, C_uint(cx, u)), |
| ty::ty_open(ty) => match ty::get(ty).sty { |
| ty::ty_vec(_, None) | ty::ty_str => { |
| let e1 = const_get_elt(cx, bv, [0]); |
| (const_deref_ptr(cx, e1), const_get_elt(cx, bv, [1])) |
| }, |
| _ => cx.sess().span_bug(base.span, |
| format!("index-expr base must be a vector \ |
| or string type, found {}", |
| ty_to_string(cx.tcx(), bt)).as_slice()) |
| }, |
| ty::ty_rptr(_, mt) => match ty::get(mt.ty).sty { |
| ty::ty_vec(_, Some(u)) => { |
| (const_deref_ptr(cx, bv), C_uint(cx, u)) |
| }, |
| _ => cx.sess().span_bug(base.span, |
| format!("index-expr base must be a vector \ |
| or string type, found {}", |
| ty_to_string(cx.tcx(), bt)).as_slice()) |
| }, |
| _ => cx.sess().span_bug(base.span, |
| format!("index-expr base must be a vector \ |
| or string type, found {}", |
| ty_to_string(cx.tcx(), bt)).as_slice()) |
| }; |
| |
| let len = llvm::LLVMConstIntGetZExtValue(len) as u64; |
| let len = match ty::get(bt).sty { |
| ty::ty_uniq(ty) | ty::ty_rptr(_, ty::mt{ty, ..}) => match ty::get(ty).sty { |
| ty::ty_str => { |
| assert!(len > 0); |
| len - 1 |
| } |
| _ => len |
| }, |
| _ => len |
| }; |
| if iv >= len { |
| // FIXME #3170: report this earlier on in the const-eval |
| // pass. Reporting here is a bit late. |
| cx.sess().span_err(e.span, |
| "const index-expr is out of bounds"); |
| } |
| const_get_elt(cx, arr, [iv as c_uint]) |
| } |
| ast::ExprCast(ref base, _) => { |
| let ety = ty::expr_ty(cx.tcx(), e); |
| let llty = type_of::type_of(cx, ety); |
| let (v, basety) = const_expr(cx, &**base); |
| return match (expr::cast_type_kind(cx.tcx(), basety), |
| expr::cast_type_kind(cx.tcx(), ety)) { |
| |
| (expr::cast_integral, expr::cast_integral) => { |
| let s = ty::type_is_signed(basety) as Bool; |
| llvm::LLVMConstIntCast(v, llty.to_ref(), s) |
| } |
| (expr::cast_integral, expr::cast_float) => { |
| if ty::type_is_signed(basety) { |
| llvm::LLVMConstSIToFP(v, llty.to_ref()) |
| } else { |
| llvm::LLVMConstUIToFP(v, llty.to_ref()) |
| } |
| } |
| (expr::cast_float, expr::cast_float) => { |
| llvm::LLVMConstFPCast(v, llty.to_ref()) |
| } |
| (expr::cast_float, expr::cast_integral) => { |
| if ty::type_is_signed(ety) { llvm::LLVMConstFPToSI(v, llty.to_ref()) } |
| else { llvm::LLVMConstFPToUI(v, llty.to_ref()) } |
| } |
| (expr::cast_enum, expr::cast_integral) => { |
| let repr = adt::represent_type(cx, basety); |
| let discr = adt::const_get_discrim(cx, &*repr, v); |
| let iv = C_integral(cx.int_type(), discr, false); |
| let ety_cast = expr::cast_type_kind(cx.tcx(), ety); |
| match ety_cast { |
| expr::cast_integral => { |
| let s = ty::type_is_signed(ety) as Bool; |
| llvm::LLVMConstIntCast(iv, llty.to_ref(), s) |
| } |
| _ => cx.sess().bug("enum cast destination is not \ |
| integral") |
| } |
| } |
| (expr::cast_pointer, expr::cast_pointer) => { |
| llvm::LLVMConstPointerCast(v, llty.to_ref()) |
| } |
| (expr::cast_integral, expr::cast_pointer) => { |
| llvm::LLVMConstIntToPtr(v, llty.to_ref()) |
| } |
| (expr::cast_pointer, expr::cast_integral) => { |
| llvm::LLVMConstPtrToInt(v, llty.to_ref()) |
| } |
| _ => { |
| cx.sess().impossible_case(e.span, |
| "bad combination of types for cast") |
| } |
| } |
| } |
| ast::ExprAddrOf(mutbl, ref sub) => { |
| // If this is the address of some static, then we need to return |
| // the actual address of the static itself (short circuit the rest |
| // of const eval). |
| let mut cur = sub; |
| loop { |
| match cur.node { |
| ast::ExprParen(ref sub) => cur = sub, |
| _ => break, |
| } |
| } |
| let opt_def = cx.tcx().def_map.borrow().find_copy(&cur.id); |
| match opt_def { |
| Some(def::DefStatic(def_id, _)) => { |
| let ty = ty::expr_ty(cx.tcx(), e); |
| return get_static_val(cx, def_id, ty); |
| } |
| _ => {} |
| } |
| |
| // If this isn't the address of a static, then keep going through |
| // normal constant evaluation. |
| let (e, _) = const_expr(cx, &**sub); |
| const_addr_of(cx, e, mutbl) |
| } |
| ast::ExprTup(ref es) => { |
| let ety = ty::expr_ty(cx.tcx(), e); |
| let repr = adt::represent_type(cx, ety); |
| let vals = map_list(es.as_slice()); |
| adt::trans_const(cx, &*repr, 0, vals.as_slice()) |
| } |
| ast::ExprStruct(_, ref fs, ref base_opt) => { |
| let ety = ty::expr_ty(cx.tcx(), e); |
| let repr = adt::represent_type(cx, ety); |
| let tcx = cx.tcx(); |
| |
| let base_val = match *base_opt { |
| Some(ref base) => Some(const_expr(cx, &**base)), |
| None => None |
| }; |
| |
| expr::with_field_tys(tcx, ety, Some(e.id), |discr, field_tys| { |
| let cs = field_tys.iter().enumerate() |
| .map(|(ix, &field_ty)| { |
| match fs.iter().find(|f| field_ty.name == f.ident.node.name) { |
| Some(ref f) => const_expr(cx, &*f.expr).val0(), |
| None => { |
| match base_val { |
| Some((bv, _)) => { |
| adt::const_get_field(cx, &*repr, bv, |
| discr, ix) |
| } |
| None => { |
| cx.sess().span_bug(e.span, |
| "missing struct field") |
| } |
| } |
| } |
| } |
| }).collect::<Vec<_>>(); |
| adt::trans_const(cx, &*repr, discr, cs.as_slice()) |
| }) |
| } |
| ast::ExprVec(ref es) => { |
| const_vec(cx, e, es.as_slice()).val0() |
| } |
| ast::ExprRepeat(ref elem, ref count) => { |
| let vec_ty = ty::expr_ty(cx.tcx(), e); |
| let unit_ty = ty::sequence_element_type(cx.tcx(), vec_ty); |
| let llunitty = type_of::type_of(cx, unit_ty); |
| let n = match const_eval::eval_const_expr(cx.tcx(), &**count) { |
| const_eval::const_int(i) => i as uint, |
| const_eval::const_uint(i) => i as uint, |
| _ => cx.sess().span_bug(count.span, "count must be integral const expression.") |
| }; |
| let vs = Vec::from_elem(n, const_expr(cx, &**elem).val0()); |
| if vs.iter().any(|vi| val_ty(*vi) != llunitty) { |
| C_struct(cx, vs.as_slice(), false) |
| } else { |
| C_array(llunitty, vs.as_slice()) |
| } |
| } |
| ast::ExprPath(ref pth) => { |
| // Assert that there are no type parameters in this path. |
| assert!(pth.segments.iter().all(|seg| seg.types.is_empty())); |
| |
| let opt_def = cx.tcx().def_map.borrow().find_copy(&e.id); |
| match opt_def { |
| Some(def::DefFn(def_id, _)) => { |
| if !ast_util::is_local(def_id) { |
| let ty = csearch::get_type(cx.tcx(), def_id).ty; |
| base::trans_external_path(cx, def_id, ty) |
| } else { |
| assert!(ast_util::is_local(def_id)); |
| base::get_item_val(cx, def_id.node) |
| } |
| } |
| Some(def::DefConst(def_id)) => { |
| get_const_val(cx, def_id) |
| } |
| Some(def::DefVariant(enum_did, variant_did, _)) => { |
| let ety = ty::expr_ty(cx.tcx(), e); |
| let repr = adt::represent_type(cx, ety); |
| let vinfo = ty::enum_variant_with_id(cx.tcx(), |
| enum_did, |
| variant_did); |
| adt::trans_const(cx, &*repr, vinfo.disr_val, []) |
| } |
| Some(def::DefStruct(_)) => { |
| let ety = ty::expr_ty(cx.tcx(), e); |
| let llty = type_of::type_of(cx, ety); |
| C_null(llty) |
| } |
| _ => { |
| cx.sess().span_bug(e.span, "expected a const, fn, struct, \ |
| or variant def") |
| } |
| } |
| } |
| ast::ExprCall(ref callee, ref args) => { |
| let opt_def = cx.tcx().def_map.borrow().find_copy(&callee.id); |
| match opt_def { |
| Some(def::DefStruct(_)) => { |
| let ety = ty::expr_ty(cx.tcx(), e); |
| let repr = adt::represent_type(cx, ety); |
| let arg_vals = map_list(args.as_slice()); |
| adt::trans_const(cx, &*repr, 0, arg_vals.as_slice()) |
| } |
| Some(def::DefVariant(enum_did, variant_did, _)) => { |
| let ety = ty::expr_ty(cx.tcx(), e); |
| let repr = adt::represent_type(cx, ety); |
| let vinfo = ty::enum_variant_with_id(cx.tcx(), |
| enum_did, |
| variant_did); |
| let arg_vals = map_list(args.as_slice()); |
| adt::trans_const(cx, |
| &*repr, |
| vinfo.disr_val, |
| arg_vals.as_slice()) |
| } |
| _ => cx.sess().span_bug(e.span, "expected a struct or variant def") |
| } |
| } |
| ast::ExprParen(ref e) => const_expr(cx, &**e).val0(), |
| ast::ExprBlock(ref block) => { |
| match block.expr { |
| Some(ref expr) => const_expr(cx, &**expr).val0(), |
| None => C_nil(cx) |
| } |
| } |
| _ => cx.sess().span_bug(e.span, |
| "bad constant expression type in consts::const_expr") |
| }; |
| } |
| } |
| |
| pub fn trans_static(ccx: &CrateContext, m: ast::Mutability, id: ast::NodeId) { |
| unsafe { |
| let _icx = push_ctxt("trans_static"); |
| let g = base::get_item_val(ccx, id); |
| // At this point, get_item_val has already translated the |
| // constant's initializer to determine its LLVM type. |
| let v = ccx.static_values().borrow().get_copy(&id); |
| // boolean SSA values are i1, but they have to be stored in i8 slots, |
| // otherwise some LLVM optimization passes don't work as expected |
| let v = if llvm::LLVMTypeOf(v) == Type::i1(ccx).to_ref() { |
| llvm::LLVMConstZExt(v, Type::i8(ccx).to_ref()) |
| } else { |
| v |
| }; |
| llvm::LLVMSetInitializer(g, v); |
| |
| // As an optimization, all shared statics which do not have interior |
| // mutability are placed into read-only memory. |
| if m != ast::MutMutable { |
| let node_ty = ty::node_id_to_type(ccx.tcx(), id); |
| let tcontents = ty::type_contents(ccx.tcx(), node_ty); |
| if !tcontents.interior_unsafe() { |
| llvm::LLVMSetGlobalConstant(g, True); |
| } |
| } |
| debuginfo::create_global_var_metadata(ccx, id, g); |
| } |
| } |
| |
| fn get_static_val(ccx: &CrateContext, did: ast::DefId, ty: ty::t) -> ValueRef { |
| if ast_util::is_local(did) { return base::get_item_val(ccx, did.node) } |
| base::trans_external_path(ccx, did, ty) |
| } |
