mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-25 08:13:41 +00:00
Add unstable -Z direct-access-external-data
cmdline flag for rustc
The new flag has been described in the Major Change Proposal at https://github.com/rust-lang/compiler-team/issues/707
This commit is contained in:
parent
94807670a6
commit
06a41687b1
@ -123,6 +123,17 @@ impl CodegenCx<'_, '_> {
|
||||
return false;
|
||||
}
|
||||
|
||||
// Match clang by only supporting COFF and ELF for now.
|
||||
if self.tcx.sess.target.is_like_osx {
|
||||
return false;
|
||||
}
|
||||
|
||||
// With pie relocation model calls of functions defined in the translation
|
||||
// unit can use copy relocations.
|
||||
if self.tcx.sess.relocation_model() == RelocModel::Pie && !is_declaration {
|
||||
return true;
|
||||
}
|
||||
|
||||
// Thread-local variables generally don't support copy relocations.
|
||||
let is_thread_local_var = llvm::LLVMIsAGlobalVariable(llval)
|
||||
.is_some_and(|v| llvm::LLVMIsThreadLocal(v) == llvm::True);
|
||||
@ -130,18 +141,12 @@ impl CodegenCx<'_, '_> {
|
||||
return false;
|
||||
}
|
||||
|
||||
// Match clang by only supporting COFF and ELF for now.
|
||||
if self.tcx.sess.target.is_like_osx {
|
||||
return false;
|
||||
// Respect the direct-access-external-data to override default behavior if present.
|
||||
if let Some(direct) = self.tcx.sess.direct_access_external_data() {
|
||||
return direct;
|
||||
}
|
||||
|
||||
// Static relocation model should force copy relocations everywhere.
|
||||
if self.tcx.sess.relocation_model() == RelocModel::Static {
|
||||
return true;
|
||||
}
|
||||
|
||||
// With pie relocation model calls of functions defined in the translation
|
||||
// unit can use copy relocations.
|
||||
self.tcx.sess.relocation_model() == RelocModel::Pie && !is_declaration
|
||||
self.tcx.sess.relocation_model() == RelocModel::Static
|
||||
}
|
||||
}
|
||||
|
@ -748,6 +748,7 @@ fn test_unstable_options_tracking_hash() {
|
||||
tracked!(debug_macros, true);
|
||||
tracked!(default_hidden_visibility, Some(true));
|
||||
tracked!(dep_info_omit_d_target, true);
|
||||
tracked!(direct_access_external_data, Some(true));
|
||||
tracked!(dual_proc_macros, true);
|
||||
tracked!(dwarf_version, Some(5));
|
||||
tracked!(emit_thin_lto, false);
|
||||
|
@ -1553,6 +1553,8 @@ options! {
|
||||
dep_info_omit_d_target: bool = (false, parse_bool, [TRACKED],
|
||||
"in dep-info output, omit targets for tracking dependencies of the dep-info files \
|
||||
themselves (default: no)"),
|
||||
direct_access_external_data: Option<bool> = (None, parse_opt_bool, [TRACKED],
|
||||
"Direct or use GOT indirect to reference external data symbols"),
|
||||
dual_proc_macros: bool = (false, parse_bool, [TRACKED],
|
||||
"load proc macros for both target and host, but only link to the target (default: no)"),
|
||||
dump_dep_graph: bool = (false, parse_bool, [UNTRACKED],
|
||||
|
@ -793,6 +793,13 @@ impl Session {
|
||||
self.opts.unstable_opts.tls_model.unwrap_or(self.target.tls_model)
|
||||
}
|
||||
|
||||
pub fn direct_access_external_data(&self) -> Option<bool> {
|
||||
self.opts
|
||||
.unstable_opts
|
||||
.direct_access_external_data
|
||||
.or(self.target.direct_access_external_data)
|
||||
}
|
||||
|
||||
pub fn split_debuginfo(&self) -> SplitDebuginfo {
|
||||
self.opts.cg.split_debuginfo.unwrap_or(self.target.split_debuginfo)
|
||||
}
|
||||
|
@ -1885,6 +1885,8 @@ pub struct TargetOptions {
|
||||
/// passed, and cannot be disabled even via `-C`. Corresponds to `llc
|
||||
/// -mattr=$features`.
|
||||
pub features: StaticCow<str>,
|
||||
/// Direct or use GOT indirect to reference external data symbols
|
||||
pub direct_access_external_data: Option<bool>,
|
||||
/// Whether dynamic linking is available on this target. Defaults to false.
|
||||
pub dynamic_linking: bool,
|
||||
/// Whether dynamic linking can export TLS globals. Defaults to true.
|
||||
@ -2279,6 +2281,7 @@ impl Default for TargetOptions {
|
||||
asm_args: cvs![],
|
||||
cpu: "generic".into(),
|
||||
features: "".into(),
|
||||
direct_access_external_data: None,
|
||||
dynamic_linking: false,
|
||||
dll_tls_export: true,
|
||||
only_cdylib: false,
|
||||
@ -2575,6 +2578,12 @@ impl Target {
|
||||
base.$key_name = s as u32;
|
||||
}
|
||||
} );
|
||||
($key_name:ident, Option<bool>) => ( {
|
||||
let name = (stringify!($key_name)).replace("_", "-");
|
||||
if let Some(s) = obj.remove(&name).and_then(|b| b.as_bool()) {
|
||||
base.$key_name = Some(s);
|
||||
}
|
||||
} );
|
||||
($key_name:ident, Option<u64>) => ( {
|
||||
let name = (stringify!($key_name)).replace("_", "-");
|
||||
if let Some(s) = obj.remove(&name).and_then(|b| b.as_u64()) {
|
||||
@ -3003,6 +3012,7 @@ impl Target {
|
||||
key!(cpu);
|
||||
key!(features);
|
||||
key!(dynamic_linking, bool);
|
||||
key!(direct_access_external_data, Option<bool>);
|
||||
key!(dll_tls_export, bool);
|
||||
key!(only_cdylib, bool);
|
||||
key!(executables, bool);
|
||||
@ -3257,6 +3267,7 @@ impl ToJson for Target {
|
||||
target_option_val!(cpu);
|
||||
target_option_val!(features);
|
||||
target_option_val!(dynamic_linking);
|
||||
target_option_val!(direct_access_external_data);
|
||||
target_option_val!(dll_tls_export);
|
||||
target_option_val!(only_cdylib);
|
||||
target_option_val!(executables);
|
||||
|
@ -11,6 +11,7 @@ pub fn target() -> Target {
|
||||
features: "+f,+d".into(),
|
||||
llvm_abiname: "lp64d".into(),
|
||||
max_atomic_width: Some(64),
|
||||
direct_access_external_data: Some(false),
|
||||
..base::linux_gnu::opts()
|
||||
},
|
||||
}
|
||||
|
@ -0,0 +1,16 @@
|
||||
# `direct_access_external_data`
|
||||
|
||||
The tracking issue for this feature is: https://github.com/rust-lang/compiler-team/issues/707
|
||||
|
||||
------------------------
|
||||
|
||||
Option `-Z direct-access-external-data` controls how to access symbols of
|
||||
external data.
|
||||
|
||||
Supported values for this option are:
|
||||
|
||||
- `yes` - Don't use GOT indirection to reference external data symbols.
|
||||
- `no` - Use GOT indirection to reference external data symbols.
|
||||
|
||||
If the option is not explicitly specified, different targets have different
|
||||
default values.
|
21
tests/codegen/direct-access-external-data.rs
Normal file
21
tests/codegen/direct-access-external-data.rs
Normal file
@ -0,0 +1,21 @@
|
||||
// only-loongarch64-unknown-linux-gnu
|
||||
|
||||
// revisions: DEFAULT DIRECT INDIRECT
|
||||
// [DEFAULT] compile-flags: -C relocation-model=static
|
||||
// [DIRECT] compile-flags: -C relocation-model=static -Z direct-access-external-data=yes
|
||||
// [INDIRECT] compile-flags: -C relocation-model=static -Z direct-access-external-data=no
|
||||
|
||||
#![crate_type = "rlib"]
|
||||
|
||||
// DEFAULT: @VAR = external {{.*}} global i32
|
||||
// DIRECT: @VAR = external dso_local {{.*}} global i32
|
||||
// INDIRECT: @VAR = external {{.*}} global i32
|
||||
|
||||
extern "C" {
|
||||
static VAR: i32;
|
||||
}
|
||||
|
||||
#[no_mangle]
|
||||
pub fn get() -> i32 {
|
||||
unsafe { VAR }
|
||||
}
|
Loading…
Reference in New Issue
Block a user