1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! # Translation of inline assembly.
13 use llvm
::{self, ValueRef}
;
23 use std
::ffi
::CString
;
24 use syntax
::ast
::AsmDialect
;
25 use libc
::{c_uint, c_char}
;
27 // Take an inline assembly expression and splat it out via LLVM
28 pub fn trans_inline_asm
<'blk
, 'tcx
>(bcx
: Block
<'blk
, 'tcx
>,
30 outputs
: Vec
<(ValueRef
, Ty
<'tcx
>)>,
31 mut inputs
: Vec
<ValueRef
>) {
32 let mut ext_constraints
= vec
![];
33 let mut output_types
= vec
![];
35 // Prepare the output operands
36 let mut indirect_outputs
= vec
![];
37 for (i
, (out
, &(val
, ty
))) in ia
.outputs
.iter().zip(&outputs
).enumerate() {
38 let val
= if out
.is_rw
|| out
.is_indirect
{
39 Some(base
::load_ty(bcx
, val
, ty
))
44 inputs
.push(val
.unwrap());
45 ext_constraints
.push(i
.to_string());
48 indirect_outputs
.push(val
.unwrap());
50 output_types
.push(type_of
::type_of(bcx
.ccx(), ty
));
53 if !indirect_outputs
.is_empty() {
54 indirect_outputs
.extend_from_slice(&inputs
);
55 inputs
= indirect_outputs
;
58 let clobbers
= ia
.clobbers
.iter()
59 .map(|s
| format
!("~{{{}}}", &s
));
61 // Default per-arch clobbers
62 // Basically what clang does
63 let arch_clobbers
= match &bcx
.sess().target
.target
.arch
[..] {
64 "x86" | "x86_64" => vec
!("~{dirflag}", "~{fpsr}", "~{flags}"),
69 ia
.outputs
.iter().map(|out
| out
.constraint
.to_string())
70 .chain(ia
.inputs
.iter().map(|s
| s
.to_string()))
71 .chain(ext_constraints
)
73 .chain(arch_clobbers
.iter().map(|s
| s
.to_string()))
74 .collect
::<Vec
<String
>>().join(",");
76 debug
!("Asm Constraints: {}", &all_constraints
[..]);
78 // Depending on how many outputs we have, the return type is different
79 let num_outputs
= output_types
.len();
80 let output_type
= match num_outputs
{
81 0 => Type
::void(bcx
.ccx()),
83 _
=> Type
::struct_(bcx
.ccx(), &output_types
[..], false)
86 let dialect
= match ia
.dialect
{
87 AsmDialect
::Att
=> llvm
::AsmDialect
::Att
,
88 AsmDialect
::Intel
=> llvm
::AsmDialect
::Intel
,
91 let asm
= CString
::new(ia
.asm
.as_bytes()).unwrap();
92 let constraint_cstr
= CString
::new(all_constraints
).unwrap();
93 let r
= InlineAsmCall(bcx
,
95 constraint_cstr
.as_ptr(),
102 // Again, based on how many outputs we have
103 let outputs
= ia
.outputs
.iter().zip(&outputs
).filter(|&(ref o
, _
)| !o
.is_indirect
);
104 for (i
, (_
, &(val
, _
))) in outputs
.enumerate() {
105 let v
= if num_outputs
== 1 { r }
else { ExtractValue(bcx, r, i) }
;
109 // Store expn_id in a metadata node so we can map LLVM errors
110 // back to source locations. See #17552.
113 let kind
= llvm
::LLVMGetMDKindIDInContext(bcx
.ccx().llcx(),
114 key
.as_ptr() as *const c_char
, key
.len() as c_uint
);
116 let val
: llvm
::ValueRef
= C_i32(bcx
.ccx(), ia
.expn_id
.into_u32() as i32);
118 llvm
::LLVMSetMetadata(r
, kind
,
119 llvm
::LLVMMDNodeInContext(bcx
.ccx().llcx(), &val
, 1));