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base.rs
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base.rs
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// Copyright 2012-2013 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.
// trans.rs: Translate the completed AST to the LLVM IR.
//
// Some functions here, such as trans_block and trans_expr, return a value --
// the result of the translation to LLVM -- while others, such as trans_fn,
// trans_impl, and trans_item, are called only for the side effect of adding a
// particular definition to the LLVM IR output we're producing.
//
// Hopefully useful general knowledge about trans:
//
// * There's no way to find out the ty::t type of a ValueRef. Doing so
// would be "trying to get the eggs out of an omelette" (credit:
// pcwalton). You can, instead, find out its TypeRef by calling val_ty,
// but many TypeRefs correspond to one ty::t; for instance, tup(int, int,
// int) and rec(x=int, y=int, z=int) will have the same TypeRef.
use back::link::{mangle_exported_name};
use back::{link, abi};
use driver::session;
use driver::session::Session;
use driver::driver::{CrateAnalysis, CrateTranslation};
use lib::llvm::{ModuleRef, ValueRef, BasicBlockRef};
use lib::llvm::{llvm, True};
use lib;
use metadata::common::LinkMeta;
use metadata::{csearch, cstore, encoder};
use middle::astencode;
use middle::lang_items::{LangItem, ExchangeMallocFnLangItem, StartFnLangItem};
use middle::lang_items::{MallocFnLangItem, ClosureExchangeMallocFnLangItem};
use middle::trans::_match;
use middle::trans::adt;
use middle::trans::base;
use middle::trans::build::*;
use middle::trans::builder::{Builder, noname};
use middle::trans::callee;
use middle::trans::common::*;
use middle::trans::consts;
use middle::trans::controlflow;
use middle::trans::datum;
use middle::trans::debuginfo;
use middle::trans::expr;
use middle::trans::foreign;
use middle::trans::glue;
use middle::trans::inline;
use middle::trans::llrepr::LlvmRepr;
use middle::trans::machine;
use middle::trans::machine::{llalign_of_min, llsize_of};
use middle::trans::meth;
use middle::trans::monomorphize;
use middle::trans::tvec;
use middle::trans::type_of;
use middle::trans::type_of::*;
use middle::trans::value::Value;
use middle::ty;
use util::common::indenter;
use util::ppaux::{Repr, ty_to_str};
use middle::trans::type_::Type;
use std::c_str::ToCStr;
use std::hash;
use std::hashmap::HashMap;
use std::libc::c_uint;
use std::vec;
use std::local_data;
use extra::time;
use extra::sort;
use syntax::ast::Name;
use syntax::ast_map::{path, path_elt_to_str, path_name, path_pretty_name};
use syntax::ast_util::{local_def};
use syntax::attr;
use syntax::attr::AttrMetaMethods;
use syntax::codemap::Span;
use syntax::parse::token;
use syntax::parse::token::{special_idents};
use syntax::print::pprust::stmt_to_str;
use syntax::{ast, ast_util, codemap, ast_map};
use syntax::abi::{X86, X86_64, Arm, Mips, Rust, RustIntrinsic, OsWin32, OsAndroid};
use syntax::visit;
use syntax::visit::Visitor;
pub use middle::trans::context::task_llcx;
local_data_key!(task_local_insn_key: ~[&'static str])
pub fn with_insn_ctxt(blk: &fn(&[&'static str])) {
do local_data::get(task_local_insn_key) |c| {
match c {
Some(ctx) => blk(*ctx),
None => ()
}
}
}
pub fn init_insn_ctxt() {
local_data::set(task_local_insn_key, ~[]);
}
pub struct _InsnCtxt { _x: () }
#[unsafe_destructor]
impl Drop for _InsnCtxt {
fn drop(&mut self) {
do local_data::modify(task_local_insn_key) |c| {
do c.map |mut ctx| {
ctx.pop();
ctx
}
}
}
}
pub fn push_ctxt(s: &'static str) -> _InsnCtxt {
debug!("new InsnCtxt: {}", s);
do local_data::modify(task_local_insn_key) |c| {
do c.map |mut ctx| {
ctx.push(s);
ctx
}
}
_InsnCtxt { _x: () }
}
struct StatRecorder<'self> {
ccx: @mut CrateContext,
name: &'self str,
start: u64,
istart: uint,
}
impl<'self> StatRecorder<'self> {
pub fn new(ccx: @mut CrateContext,
name: &'self str) -> StatRecorder<'self> {
let start = if ccx.sess.trans_stats() {
time::precise_time_ns()
} else {
0
};
let istart = ccx.stats.n_llvm_insns;
StatRecorder {
ccx: ccx,
name: name,
start: start,
istart: istart,
}
}
}
#[unsafe_destructor]
impl<'self> Drop for StatRecorder<'self> {
fn drop(&mut self) {
if self.ccx.sess.trans_stats() {
let end = time::precise_time_ns();
let elapsed = ((end - self.start) / 1_000_000) as uint;
let iend = self.ccx.stats.n_llvm_insns;
self.ccx.stats.fn_stats.push((self.name.to_owned(),
elapsed,
iend - self.istart));
self.ccx.stats.n_fns += 1;
// Reset LLVM insn count to avoid compound costs.
self.ccx.stats.n_llvm_insns = self.istart;
}
}
}
// only use this for foreign function ABIs and glue, use `decl_rust_fn` for Rust functions
pub fn decl_fn(llmod: ModuleRef, name: &str, cc: lib::llvm::CallConv, ty: Type) -> ValueRef {
let llfn: ValueRef = do name.with_c_str |buf| {
unsafe {
llvm::LLVMGetOrInsertFunction(llmod, buf, ty.to_ref())
}
};
lib::llvm::SetFunctionCallConv(llfn, cc);
// Function addresses in Rust are never significant, allowing functions to be merged.
lib::llvm::SetUnnamedAddr(llfn, true);
return llfn;
}
// only use this for foreign function ABIs and glue, use `decl_rust_fn` for Rust functions
pub fn decl_cdecl_fn(llmod: ModuleRef, name: &str, ty: Type) -> ValueRef {
return decl_fn(llmod, name, lib::llvm::CCallConv, ty);
}
// only use this for foreign function ABIs and glue, use `get_extern_rust_fn` for Rust functions
pub fn get_extern_fn(externs: &mut ExternMap, llmod: ModuleRef, name: &str,
cc: lib::llvm::CallConv, ty: Type) -> ValueRef {
match externs.find_equiv(&name) {
Some(n) => return *n,
None => ()
}
let f = decl_fn(llmod, name, cc, ty);
externs.insert(name.to_owned(), f);
f
}
fn get_extern_rust_fn(ccx: &mut CrateContext, inputs: &[ty::t], output: ty::t,
name: &str, did: ast::DefId) -> ValueRef {
match ccx.externs.find_equiv(&name) {
Some(n) => return *n,
None => ()
}
let f = decl_rust_fn(ccx, inputs, output, name);
do csearch::get_item_attrs(ccx.tcx.cstore, did) |meta_items| {
set_llvm_fn_attrs(meta_items.iter().map(|&x| attr::mk_attr(x)).to_owned_vec(), f)
}
ccx.externs.insert(name.to_owned(), f);
f
}
fn decl_rust_fn(ccx: &mut CrateContext, inputs: &[ty::t], output: ty::t, name: &str) -> ValueRef {
let llfty = type_of_rust_fn(ccx, inputs, output);
let llfn = decl_cdecl_fn(ccx.llmod, name, llfty);
match ty::get(output).sty {
// functions returning bottom may unwind, but can never return normally
ty::ty_bot => {
unsafe {
llvm::LLVMAddFunctionAttr(llfn, lib::llvm::NoReturnAttribute as c_uint)
}
}
// `~` pointer return values never alias because ownership is transferred
ty::ty_uniq(*) |
ty::ty_evec(_, ty::vstore_uniq) => {
unsafe {
llvm::LLVMAddReturnAttribute(llfn, lib::llvm::NoAliasAttribute as c_uint);
}
}
_ => ()
}
let uses_outptr = type_of::return_uses_outptr(ccx, output);
let offset = if uses_outptr { 2 } else { 1 };
for (i, &arg_ty) in inputs.iter().enumerate() {
let llarg = unsafe { llvm::LLVMGetParam(llfn, (offset + i) as c_uint) };
match ty::get(arg_ty).sty {
// `~` pointer parameters never alias because ownership is transferred
ty::ty_uniq(*) |
ty::ty_evec(_, ty::vstore_uniq) |
ty::ty_closure(ty::ClosureTy {sigil: ast::OwnedSigil, _}) => {
unsafe {
llvm::LLVMAddAttribute(llarg, lib::llvm::NoAliasAttribute as c_uint);
}
}
_ => ()
}
}
// The out pointer will never alias with any other pointers, as the object only exists at a
// language level after the call. It can also be tagged with SRet to indicate that it is
// guaranteed to point to a usable block of memory for the type.
if uses_outptr {
unsafe {
let outptr = llvm::LLVMGetParam(llfn, 0);
llvm::LLVMAddAttribute(outptr, lib::llvm::StructRetAttribute as c_uint);
llvm::LLVMAddAttribute(outptr, lib::llvm::NoAliasAttribute as c_uint);
}
}
llfn
}
pub fn decl_internal_rust_fn(ccx: &mut CrateContext, inputs: &[ty::t], output: ty::t,
name: &str) -> ValueRef {
let llfn = decl_rust_fn(ccx, inputs, output, name);
lib::llvm::SetLinkage(llfn, lib::llvm::InternalLinkage);
llfn
}
pub fn get_extern_const(externs: &mut ExternMap, llmod: ModuleRef,
name: &str, ty: Type) -> ValueRef {
match externs.find_equiv(&name) {
Some(n) => return *n,
None => ()
}
unsafe {
let c = do name.with_c_str |buf| {
llvm::LLVMAddGlobal(llmod, ty.to_ref(), buf)
};
externs.insert(name.to_owned(), c);
return c;
}
}
// Returns a pointer to the body for the box. The box may be an opaque
// box. The result will be casted to the type of body_t, if it is statically
// known.
//
// The runtime equivalent is box_body() in "rust_internal.h".
pub fn opaque_box_body(bcx: @mut Block,
body_t: ty::t,
boxptr: ValueRef) -> ValueRef {
let _icx = push_ctxt("opaque_box_body");
let ccx = bcx.ccx();
let ty = type_of(ccx, body_t);
let ty = Type::box(ccx, &ty);
let boxptr = PointerCast(bcx, boxptr, ty.ptr_to());
GEPi(bcx, boxptr, [0u, abi::box_field_body])
}
// malloc_raw_dyn: allocates a box to contain a given type, but with a
// potentially dynamic size.
pub fn malloc_raw_dyn(bcx: @mut Block,
t: ty::t,
heap: heap,
size: ValueRef) -> Result {
let _icx = push_ctxt("malloc_raw");
let ccx = bcx.ccx();
fn require_alloc_fn(bcx: @mut Block, t: ty::t, it: LangItem) -> ast::DefId {
let li = &bcx.tcx().lang_items;
match li.require(it) {
Ok(id) => id,
Err(s) => {
bcx.tcx().sess.fatal(format!("allocation of `{}` {}",
bcx.ty_to_str(t), s));
}
}
}
if heap == heap_exchange {
let llty_value = type_of::type_of(ccx, t);
// Allocate space:
let r = callee::trans_lang_call(
bcx,
require_alloc_fn(bcx, t, ExchangeMallocFnLangItem),
[size],
None);
rslt(r.bcx, PointerCast(r.bcx, r.val, llty_value.ptr_to()))
} else {
// we treat ~fn, @fn and @[] as @ here, which isn't ideal
let (mk_fn, langcall) = match heap {
heap_managed | heap_managed_unique => {
(ty::mk_imm_box,
require_alloc_fn(bcx, t, MallocFnLangItem))
}
heap_exchange_closure => {
(ty::mk_imm_box,
require_alloc_fn(bcx, t, ClosureExchangeMallocFnLangItem))
}
_ => fail!("heap_exchange already handled")
};
// Grab the TypeRef type of box_ptr_ty.
let box_ptr_ty = mk_fn(bcx.tcx(), t);
let llty = type_of(ccx, box_ptr_ty);
// Get the tydesc for the body:
let static_ti = get_tydesc(ccx, t);
glue::lazily_emit_all_tydesc_glue(ccx, static_ti);
// Allocate space:
let tydesc = PointerCast(bcx, static_ti.tydesc, Type::i8p());
let r = callee::trans_lang_call(
bcx,
langcall,
[tydesc, size],
None);
let r = rslt(r.bcx, PointerCast(r.bcx, r.val, llty));
maybe_set_managed_unique_rc(r.bcx, r.val, heap);
r
}
}
// malloc_raw: expects an unboxed type and returns a pointer to
// enough space for a box of that type. This includes a rust_opaque_box
// header.
pub fn malloc_raw(bcx: @mut Block, t: ty::t, heap: heap) -> Result {
let ty = type_of(bcx.ccx(), t);
let size = llsize_of(bcx.ccx(), ty);
malloc_raw_dyn(bcx, t, heap, size)
}
pub struct MallocResult {
bcx: @mut Block,
box: ValueRef,
body: ValueRef
}
// malloc_general_dyn: usefully wraps malloc_raw_dyn; allocates a box,
// and pulls out the body
pub fn malloc_general_dyn(bcx: @mut Block, t: ty::t, heap: heap, size: ValueRef)
-> MallocResult {
assert!(heap != heap_exchange);
let _icx = push_ctxt("malloc_general");
let Result {bcx: bcx, val: llbox} = malloc_raw_dyn(bcx, t, heap, size);
let body = GEPi(bcx, llbox, [0u, abi::box_field_body]);
MallocResult { bcx: bcx, box: llbox, body: body }
}
pub fn malloc_general(bcx: @mut Block, t: ty::t, heap: heap) -> MallocResult {
let ty = type_of(bcx.ccx(), t);
assert!(heap != heap_exchange);
malloc_general_dyn(bcx, t, heap, llsize_of(bcx.ccx(), ty))
}
pub fn heap_for_unique(bcx: @mut Block, t: ty::t) -> heap {
if ty::type_contents(bcx.tcx(), t).owns_managed() {
heap_managed_unique
} else {
heap_exchange
}
}
pub fn maybe_set_managed_unique_rc(bcx: @mut Block, bx: ValueRef, heap: heap) {
assert!(heap != heap_exchange);
if heap == heap_managed_unique {
// In cases where we are looking at a unique-typed allocation in the
// managed heap (thus have refcount 1 from the managed allocator),
// such as a ~(@foo) or such. These need to have their refcount forced
// to -2 so the annihilator ignores them.
let rc = GEPi(bcx, bx, [0u, abi::box_field_refcnt]);
let rc_val = C_int(bcx.ccx(), -2);
Store(bcx, rc_val, rc);
}
}
// Type descriptor and type glue stuff
pub fn get_tydesc_simple(ccx: &mut CrateContext, t: ty::t) -> ValueRef {
get_tydesc(ccx, t).tydesc
}
pub fn get_tydesc(ccx: &mut CrateContext, t: ty::t) -> @mut tydesc_info {
match ccx.tydescs.find(&t) {
Some(&inf) => {
return inf;
}
_ => { }
}
ccx.stats.n_static_tydescs += 1u;
let inf = glue::declare_tydesc(ccx, t);
ccx.tydescs.insert(t, inf);
return inf;
}
pub fn set_optimize_for_size(f: ValueRef) {
lib::llvm::SetFunctionAttribute(f, lib::llvm::OptimizeForSizeAttribute)
}
pub fn set_no_inline(f: ValueRef) {
lib::llvm::SetFunctionAttribute(f, lib::llvm::NoInlineAttribute)
}
pub fn set_no_unwind(f: ValueRef) {
lib::llvm::SetFunctionAttribute(f, lib::llvm::NoUnwindAttribute)
}
// Tell LLVM to emit the information necessary to unwind the stack for the
// function f.
pub fn set_uwtable(f: ValueRef) {
lib::llvm::SetFunctionAttribute(f, lib::llvm::UWTableAttribute)
}
pub fn set_inline_hint(f: ValueRef) {
lib::llvm::SetFunctionAttribute(f, lib::llvm::InlineHintAttribute)
}
pub fn set_llvm_fn_attrs(attrs: &[ast::Attribute], llfn: ValueRef) {
use syntax::attr::*;
// Set the inline hint if there is one
match find_inline_attr(attrs) {
InlineHint => set_inline_hint(llfn),
InlineAlways => set_always_inline(llfn),
InlineNever => set_no_inline(llfn),
InlineNone => { /* fallthrough */ }
}
// Add the no-split-stack attribute if requested
if contains_name(attrs, "no_split_stack") {
set_no_split_stack(llfn);
}
if contains_name(attrs, "cold") {
unsafe { llvm::LLVMAddColdAttribute(llfn) }
}
}
pub fn set_always_inline(f: ValueRef) {
lib::llvm::SetFunctionAttribute(f, lib::llvm::AlwaysInlineAttribute)
}
pub fn set_no_split_stack(f: ValueRef) {
do "no-split-stack".with_c_str |buf| {
unsafe { llvm::LLVMAddFunctionAttrString(f, buf); }
}
}
// Double-check that we never ask LLVM to declare the same symbol twice. It
// silently mangles such symbols, breaking our linkage model.
pub fn note_unique_llvm_symbol(ccx: &mut CrateContext, sym: @str) {
if ccx.all_llvm_symbols.contains(&sym) {
ccx.sess.bug(~"duplicate LLVM symbol: " + sym);
}
ccx.all_llvm_symbols.insert(sym);
}
pub fn get_res_dtor(ccx: @mut CrateContext,
did: ast::DefId,
parent_id: ast::DefId,
substs: &[ty::t])
-> ValueRef {
let _icx = push_ctxt("trans_res_dtor");
let did = if did.crate != ast::LOCAL_CRATE {
inline::maybe_instantiate_inline(ccx, did)
} else {
did
};
if !substs.is_empty() {
assert_eq!(did.crate, ast::LOCAL_CRATE);
let tsubsts = ty::substs {regions: ty::ErasedRegions,
self_ty: None,
tps: /*bad*/ substs.to_owned() };
// FIXME: #4252: Generic destructors with type bounds are broken.
//
// Since the vtables aren't passed to `monomorphic_fn` here, generic destructors with type
// bounds are broken. Sadly, the `typeck` pass isn't outputting the necessary metadata
// because it does so based on method calls present in the AST. Destructor calls are not yet
// known about at that stage of compilation, since `trans` handles cleanups.
let (val, _) = monomorphize::monomorphic_fn(ccx,
did,
&tsubsts,
None,
None,
None);
val
} else if did.crate == ast::LOCAL_CRATE {
get_item_val(ccx, did.node)
} else {
let tcx = ccx.tcx;
let name = csearch::get_symbol(ccx.sess.cstore, did);
let class_ty = ty::subst_tps(tcx,
substs,
None,
ty::lookup_item_type(tcx, parent_id).ty);
let llty = type_of_dtor(ccx, class_ty);
get_extern_fn(&mut ccx.externs,
ccx.llmod,
name,
lib::llvm::CCallConv,
llty)
}
}
// Structural comparison: a rather involved form of glue.
pub fn maybe_name_value(cx: &CrateContext, v: ValueRef, s: &str) {
if cx.sess.opts.save_temps {
do s.with_c_str |buf| {
unsafe {
llvm::LLVMSetValueName(v, buf)
}
}
}
}
// Used only for creating scalar comparison glue.
pub enum scalar_type { nil_type, signed_int, unsigned_int, floating_point, }
// NB: This produces an i1, not a Rust bool (i8).
pub fn compare_scalar_types(cx: @mut Block,
lhs: ValueRef,
rhs: ValueRef,
t: ty::t,
op: ast::BinOp)
-> Result {
let f = |a| compare_scalar_values(cx, lhs, rhs, a, op);
match ty::get(t).sty {
ty::ty_nil => rslt(cx, f(nil_type)),
ty::ty_bool | ty::ty_ptr(_) => rslt(cx, f(unsigned_int)),
ty::ty_char => rslt(cx, f(unsigned_int)),
ty::ty_int(_) => rslt(cx, f(signed_int)),
ty::ty_uint(_) => rslt(cx, f(unsigned_int)),
ty::ty_float(_) => rslt(cx, f(floating_point)),
ty::ty_type => {
rslt(
controlflow::trans_fail(
cx, None,
@"attempt to compare values of type type"),
C_nil())
}
_ => {
// Should never get here, because t is scalar.
cx.sess().bug("non-scalar type passed to \
compare_scalar_types")
}
}
}
// A helper function to do the actual comparison of scalar values.
pub fn compare_scalar_values(cx: @mut Block,
lhs: ValueRef,
rhs: ValueRef,
nt: scalar_type,
op: ast::BinOp)
-> ValueRef {
let _icx = push_ctxt("compare_scalar_values");
fn die(cx: @mut Block) -> ! {
cx.tcx().sess.bug("compare_scalar_values: must be a\
comparison operator");
}
match nt {
nil_type => {
// We don't need to do actual comparisons for nil.
// () == () holds but () < () does not.
match op {
ast::BiEq | ast::BiLe | ast::BiGe => return C_i1(true),
ast::BiNe | ast::BiLt | ast::BiGt => return C_i1(false),
// refinements would be nice
_ => die(cx)
}
}
floating_point => {
let cmp = match op {
ast::BiEq => lib::llvm::RealOEQ,
ast::BiNe => lib::llvm::RealUNE,
ast::BiLt => lib::llvm::RealOLT,
ast::BiLe => lib::llvm::RealOLE,
ast::BiGt => lib::llvm::RealOGT,
ast::BiGe => lib::llvm::RealOGE,
_ => die(cx)
};
return FCmp(cx, cmp, lhs, rhs);
}
signed_int => {
let cmp = match op {
ast::BiEq => lib::llvm::IntEQ,
ast::BiNe => lib::llvm::IntNE,
ast::BiLt => lib::llvm::IntSLT,
ast::BiLe => lib::llvm::IntSLE,
ast::BiGt => lib::llvm::IntSGT,
ast::BiGe => lib::llvm::IntSGE,
_ => die(cx)
};
return ICmp(cx, cmp, lhs, rhs);
}
unsigned_int => {
let cmp = match op {
ast::BiEq => lib::llvm::IntEQ,
ast::BiNe => lib::llvm::IntNE,
ast::BiLt => lib::llvm::IntULT,
ast::BiLe => lib::llvm::IntULE,
ast::BiGt => lib::llvm::IntUGT,
ast::BiGe => lib::llvm::IntUGE,
_ => die(cx)
};
return ICmp(cx, cmp, lhs, rhs);
}
}
}
pub type val_and_ty_fn<'self> = &'self fn(@mut Block, ValueRef, ty::t) -> @mut Block;
pub fn load_inbounds(cx: @mut Block, p: ValueRef, idxs: &[uint]) -> ValueRef {
return Load(cx, GEPi(cx, p, idxs));
}
pub fn store_inbounds(cx: @mut Block, v: ValueRef, p: ValueRef, idxs: &[uint]) {
Store(cx, v, GEPi(cx, p, idxs));
}
// Iterates through the elements of a structural type.
pub fn iter_structural_ty(cx: @mut Block, av: ValueRef, t: ty::t,
f: val_and_ty_fn) -> @mut Block {
let _icx = push_ctxt("iter_structural_ty");
fn iter_variant(cx: @mut Block, repr: &adt::Repr, av: ValueRef,
variant: @ty::VariantInfo,
tps: &[ty::t], f: val_and_ty_fn) -> @mut Block {
let _icx = push_ctxt("iter_variant");
let tcx = cx.tcx();
let mut cx = cx;
for (i, &arg) in variant.args.iter().enumerate() {
cx = f(cx,
adt::trans_field_ptr(cx, repr, av, variant.disr_val, i),
ty::subst_tps(tcx, tps, None, arg));
}
return cx;
}
let mut cx = cx;
match ty::get(t).sty {
ty::ty_struct(*) => {
let repr = adt::represent_type(cx.ccx(), t);
do expr::with_field_tys(cx.tcx(), t, None) |discr, field_tys| {
for (i, field_ty) in field_tys.iter().enumerate() {
let llfld_a = adt::trans_field_ptr(cx, repr, av, discr, i);
cx = f(cx, llfld_a, field_ty.mt.ty);
}
}
}
ty::ty_estr(ty::vstore_fixed(_)) |
ty::ty_evec(_, ty::vstore_fixed(_)) => {
let (base, len) = tvec::get_base_and_byte_len(cx, av, t);
cx = tvec::iter_vec_raw(cx, base, t, len, f);
}
ty::ty_tup(ref args) => {
let repr = adt::represent_type(cx.ccx(), t);
for (i, arg) in args.iter().enumerate() {
let llfld_a = adt::trans_field_ptr(cx, repr, av, 0, i);
cx = f(cx, llfld_a, *arg);
}
}
ty::ty_enum(tid, ref substs) => {
let ccx = cx.ccx();
let repr = adt::represent_type(ccx, t);
let variants = ty::enum_variants(ccx.tcx, tid);
let n_variants = (*variants).len();
// NB: we must hit the discriminant first so that structural
// comparison know not to proceed when the discriminants differ.
match adt::trans_switch(cx, repr, av) {
(_match::single, None) => {
cx = iter_variant(cx, repr, av, variants[0],
substs.tps, f);
}
(_match::switch, Some(lldiscrim_a)) => {
cx = f(cx, lldiscrim_a, ty::mk_int());
let unr_cx = sub_block(cx, "enum-iter-unr");
Unreachable(unr_cx);
let llswitch = Switch(cx, lldiscrim_a, unr_cx.llbb,
n_variants);
let next_cx = sub_block(cx, "enum-iter-next");
for variant in (*variants).iter() {
let variant_cx =
sub_block(cx, ~"enum-iter-variant-" +
variant.disr_val.to_str());
let variant_cx =
iter_variant(variant_cx, repr, av, *variant,
substs.tps, |x,y,z| f(x,y,z));
match adt::trans_case(cx, repr, variant.disr_val) {
_match::single_result(r) => {
AddCase(llswitch, r.val, variant_cx.llbb)
}
_ => ccx.sess.unimpl("value from adt::trans_case \
in iter_structural_ty")
}
Br(variant_cx, next_cx.llbb);
}
cx = next_cx;
}
_ => ccx.sess.unimpl("value from adt::trans_switch \
in iter_structural_ty")
}
}
_ => cx.sess().unimpl("type in iter_structural_ty")
}
return cx;
}
pub fn cast_shift_expr_rhs(cx: @mut Block, op: ast::BinOp,
lhs: ValueRef, rhs: ValueRef) -> ValueRef {
cast_shift_rhs(op, lhs, rhs,
|a,b| Trunc(cx, a, b),
|a,b| ZExt(cx, a, b))
}
pub fn cast_shift_const_rhs(op: ast::BinOp,
lhs: ValueRef, rhs: ValueRef) -> ValueRef {
cast_shift_rhs(op, lhs, rhs,
|a, b| unsafe { llvm::LLVMConstTrunc(a, b.to_ref()) },
|a, b| unsafe { llvm::LLVMConstZExt(a, b.to_ref()) })
}
pub fn cast_shift_rhs(op: ast::BinOp,
lhs: ValueRef, rhs: ValueRef,
trunc: &fn(ValueRef, Type) -> ValueRef,
zext: &fn(ValueRef, Type) -> ValueRef)
-> ValueRef {
// Shifts may have any size int on the rhs
unsafe {
if ast_util::is_shift_binop(op) {
let rhs_llty = val_ty(rhs);
let lhs_llty = val_ty(lhs);
let rhs_sz = llvm::LLVMGetIntTypeWidth(rhs_llty.to_ref());
let lhs_sz = llvm::LLVMGetIntTypeWidth(lhs_llty.to_ref());
if lhs_sz < rhs_sz {
trunc(rhs, lhs_llty)
} else if lhs_sz > rhs_sz {
// FIXME (#1877: If shifting by negative
// values becomes not undefined then this is wrong.
zext(rhs, lhs_llty)
} else {
rhs
}
} else {
rhs
}
}
}
pub fn fail_if_zero(cx: @mut Block, span: Span, divrem: ast::BinOp,
rhs: ValueRef, rhs_t: ty::t) -> @mut Block {
let text = if divrem == ast::BiDiv {
@"attempted to divide by zero"
} else {
@"attempted remainder with a divisor of zero"
};
let is_zero = match ty::get(rhs_t).sty {
ty::ty_int(t) => {
let zero = C_integral(Type::int_from_ty(cx.ccx(), t), 0u64, false);
ICmp(cx, lib::llvm::IntEQ, rhs, zero)
}
ty::ty_uint(t) => {
let zero = C_integral(Type::uint_from_ty(cx.ccx(), t), 0u64, false);
ICmp(cx, lib::llvm::IntEQ, rhs, zero)
}
_ => {
cx.tcx().sess.bug(~"fail-if-zero on unexpected type: " +
ty_to_str(cx.ccx().tcx, rhs_t));
}
};
do with_cond(cx, is_zero) |bcx| {
controlflow::trans_fail(bcx, Some(span), text)
}
}
pub fn null_env_ptr(ccx: &CrateContext) -> ValueRef {
C_null(Type::opaque_box(ccx).ptr_to())
}
pub fn trans_external_path(ccx: &mut CrateContext, did: ast::DefId, t: ty::t) -> ValueRef {
let name = csearch::get_symbol(ccx.sess.cstore, did);
match ty::get(t).sty {
ty::ty_bare_fn(ref fn_ty) => {
match fn_ty.abis.for_target(ccx.sess.targ_cfg.os,
ccx.sess.targ_cfg.arch) {
Some(Rust) | Some(RustIntrinsic) => {
get_extern_rust_fn(ccx, fn_ty.sig.inputs, fn_ty.sig.output, name, did)
}
Some(*) | None => {
let c = foreign::llvm_calling_convention(ccx, fn_ty.abis);
let cconv = c.unwrap_or(lib::llvm::CCallConv);
let llty = type_of_fn_from_ty(ccx, t);
get_extern_fn(&mut ccx.externs, ccx.llmod, name, cconv, llty)
}
}
}
ty::ty_closure(ref f) => {
get_extern_rust_fn(ccx, f.sig.inputs, f.sig.output, name, did)
}
_ => {
let llty = type_of(ccx, t);
get_extern_const(&mut ccx.externs, ccx.llmod, name, llty)
}
}
}
pub fn invoke(bcx: @mut Block, llfn: ValueRef, llargs: ~[ValueRef],
attributes: &[(uint, lib::llvm::Attribute)])
-> (ValueRef, @mut Block) {
let _icx = push_ctxt("invoke_");
if bcx.unreachable {
return (C_null(Type::i8()), bcx);
}
match bcx.node_info {
None => debug!("invoke at ???"),
Some(node_info) => {
debug!("invoke at {}",
bcx.sess().codemap.span_to_str(node_info.span));
}
}
if need_invoke(bcx) {
unsafe {
debug!("invoking {} at {}", llfn, bcx.llbb);
for &llarg in llargs.iter() {
debug!("arg: {}", llarg);
}
}
let normal_bcx = sub_block(bcx, "normal return");
let llresult = Invoke(bcx,
llfn,
llargs,
normal_bcx.llbb,
get_landing_pad(bcx),
attributes);
return (llresult, normal_bcx);
} else {
unsafe {
debug!("calling {} at {}", llfn, bcx.llbb);
for &llarg in llargs.iter() {
debug!("arg: {}", llarg);
}
}
let llresult = Call(bcx, llfn, llargs, attributes);
return (llresult, bcx);
}
}
pub fn need_invoke(bcx: @mut Block) -> bool {
if (bcx.ccx().sess.opts.debugging_opts & session::no_landing_pads != 0) {
return false;
}
// Avoid using invoke if we are already inside a landing pad.
if bcx.is_lpad {
return false;
}
if have_cached_lpad(bcx) {
return true;
}
// Walk the scopes to look for cleanups
let mut cur = bcx;
let mut cur_scope = cur.scope;
loop {
cur_scope = match cur_scope {
Some(inf) => {
for cleanup in inf.cleanups.iter() {
match *cleanup {
clean(_, cleanup_type) | clean_temp(_, _, cleanup_type) => {
if cleanup_type == normal_exit_and_unwind {
return true;
}
}
}
}
inf.parent
}
None => {
cur = match cur.parent {
Some(next) => next,
None => return false
};
cur.scope
}
}
}
}
pub fn have_cached_lpad(bcx: @mut Block) -> bool {
let mut res = false;
do in_lpad_scope_cx(bcx) |inf| {
match inf.landing_pad {
Some(_) => res = true,
None => res = false
}
}
return res;
}
pub fn in_lpad_scope_cx(bcx: @mut Block, f: &fn(si: &mut ScopeInfo)) {
let mut bcx = bcx;
let mut cur_scope = bcx.scope;
loop {
cur_scope = match cur_scope {
Some(inf) => {
if !inf.empty_cleanups() || (inf.parent.is_none() && bcx.parent.is_none()) {
f(inf);
return;
}
inf.parent
}
None => {
bcx = block_parent(bcx);
bcx.scope
}
}
}
}
pub fn get_landing_pad(bcx: @mut Block) -> BasicBlockRef {
let _icx = push_ctxt("get_landing_pad");
let mut cached = None;
let mut pad_bcx = bcx; // Guaranteed to be set below
do in_lpad_scope_cx(bcx) |inf| {
// If there is a valid landing pad still around, use it
match inf.landing_pad {
Some(target) => cached = Some(target),
None => {
pad_bcx = lpad_block(bcx, "unwind");
inf.landing_pad = Some(pad_bcx.llbb);