Allow for opting out of ThinLTO and clean up LTO related cli flag handling.
diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index ee3fabc..28e473a 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -68,15 +68,13 @@
SizeMin, // -Oz
}
+/// This is what the `LtoCli` values get mapped to after resolving defaults and
+/// and taking other command line options into account.
#[derive(Clone, Copy, PartialEq, Hash, Debug)]
pub enum Lto {
/// Don't do any LTO whatsoever
No,
- /// Do a full crate graph LTO. The flavor is determined by the compiler
- /// (currently the default is "fat").
- Yes,
-
/// Do a full crate graph LTO with ThinLTO
Thin,
@@ -88,6 +86,23 @@
Fat,
}
+/// The different settings that the `-C lto` flag can have.
+#[derive(Clone, Copy, PartialEq, Hash, Debug)]
+pub enum LtoCli {
+ /// `-C lto=no`
+ No,
+ /// `-C lto=yes`
+ Yes,
+ /// `-C lto`
+ NoParam,
+ /// `-C lto=thin`
+ Thin,
+ /// `-C lto=fat`
+ Fat,
+ /// No `-C lto` flag passed
+ Unspecified,
+}
+
#[derive(Clone, PartialEq, Hash)]
pub enum CrossLangLto {
LinkerPlugin(PathBuf),
@@ -801,7 +816,8 @@
pub const parse_unpretty: Option<&'static str> =
Some("`string` or `string=string`");
pub const parse_lto: Option<&'static str> =
- Some("one of `thin`, `fat`, or omitted");
+ Some("either a boolean (`yes`, `no`, `on`, `off`, etc), `thin`, \
+ `fat`, or omitted");
pub const parse_cross_lang_lto: Option<&'static str> =
Some("either a boolean (`yes`, `no`, `on`, `off`, etc), \
or the path to the linker plugin");
@@ -809,7 +825,7 @@
#[allow(dead_code)]
mod $mod_set {
- use super::{$struct_name, Passes, Sanitizer, Lto, CrossLangLto};
+ use super::{$struct_name, Passes, Sanitizer, LtoCli, CrossLangLto};
use rustc_target::spec::{LinkerFlavor, PanicStrategy, RelroLevel};
use std::path::PathBuf;
@@ -1002,11 +1018,23 @@
}
}
- fn parse_lto(slot: &mut Lto, v: Option<&str>) -> bool {
+ fn parse_lto(slot: &mut LtoCli, v: Option<&str>) -> bool {
+ if v.is_some() {
+ let mut bool_arg = None;
+ if parse_opt_bool(&mut bool_arg, v) {
+ *slot = if bool_arg.unwrap() {
+ LtoCli::Yes
+ } else {
+ LtoCli::No
+ };
+ return true
+ }
+ }
+
*slot = match v {
- None => Lto::Yes,
- Some("thin") => Lto::Thin,
- Some("fat") => Lto::Fat,
+ None => LtoCli::NoParam,
+ Some("thin") => LtoCli::Thin,
+ Some("fat") => LtoCli::Fat,
Some(_) => return false,
};
true
@@ -1047,7 +1075,7 @@
"extra arguments to append to the linker invocation (space separated)"),
link_dead_code: bool = (false, parse_bool, [UNTRACKED],
"don't let linker strip dead code (turning it on can be used for code coverage)"),
- lto: Lto = (Lto::No, parse_lto, [TRACKED],
+ lto: LtoCli = (LtoCli::Unspecified, parse_lto, [TRACKED],
"perform LLVM link-time optimizations"),
target_cpu: Option<String> = (None, parse_opt_string, [TRACKED],
"select target processor (rustc --print target-cpus for details)"),
@@ -2373,8 +2401,8 @@
use std::hash::Hash;
use std::path::PathBuf;
use std::collections::hash_map::DefaultHasher;
- use super::{CrateType, DebugInfo, ErrorOutputType, Lto, OptLevel, OutputTypes,
- Passes, Sanitizer, CrossLangLto};
+ use super::{CrateType, DebugInfo, ErrorOutputType, OptLevel, OutputTypes,
+ Passes, Sanitizer, LtoCli, CrossLangLto};
use syntax::feature_gate::UnstableFeatures;
use rustc_target::spec::{PanicStrategy, RelroLevel, TargetTriple};
use syntax::edition::Edition;
@@ -2429,7 +2457,7 @@
impl_dep_tracking_hash_via_hash!(RelroLevel);
impl_dep_tracking_hash_via_hash!(Passes);
impl_dep_tracking_hash_via_hash!(OptLevel);
- impl_dep_tracking_hash_via_hash!(Lto);
+ impl_dep_tracking_hash_via_hash!(LtoCli);
impl_dep_tracking_hash_via_hash!(DebugInfo);
impl_dep_tracking_hash_via_hash!(UnstableFeatures);
impl_dep_tracking_hash_via_hash!(OutputTypes);
@@ -2503,7 +2531,7 @@
use lint;
use middle::cstore;
use session::config::{build_configuration, build_session_options_and_crate_config};
- use session::config::{Lto, CrossLangLto};
+ use session::config::{LtoCli, CrossLangLto};
use session::build_session;
use std::collections::{BTreeMap, BTreeSet};
use std::iter::FromIterator;
@@ -2937,7 +2965,7 @@
// Make sure changing a [TRACKED] option changes the hash
opts = reference.clone();
- opts.cg.lto = Lto::Fat;
+ opts.cg.lto = LtoCli::Fat;
assert!(reference.dep_tracking_hash() != opts.dep_tracking_hash());
opts = reference.clone();
diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs
index 778c388..9e99d3a 100644
--- a/src/librustc/session/mod.rs
+++ b/src/librustc/session/mod.rs
@@ -547,9 +547,27 @@
// lto` and we've for whatever reason forced off ThinLTO via the CLI,
// then ensure we can't use a ThinLTO.
match self.opts.cg.lto {
- config::Lto::No => {}
- config::Lto::Yes if self.opts.cli_forced_thinlto_off => return config::Lto::Fat,
- other => return other,
+ config::LtoCli::Unspecified => {
+ // The compiler was invoked without the `-Clto` flag. Fall
+ // through to the default handling
+ }
+ config::LtoCli::No => {
+ // The user explicitly opted out of any kind of LTO
+ return config::Lto::No;
+ }
+ config::LtoCli::Yes |
+ config::LtoCli::Fat |
+ config::LtoCli::NoParam => {
+ // All of these mean fat LTO
+ return config::Lto::Fat;
+ }
+ config::LtoCli::Thin => {
+ return if self.opts.cli_forced_thinlto_off {
+ config::Lto::Fat
+ } else {
+ config::Lto::Thin
+ };
+ }
}
// Ok at this point the target doesn't require anything and the user
@@ -1174,7 +1192,6 @@
if sess.opts.incremental.is_some() {
match sess.lto() {
- Lto::Yes |
Lto::Thin |
Lto::Fat => {
sess.err("can't perform LTO when compiling incrementally");
diff --git a/src/librustc_codegen_llvm/back/link.rs b/src/librustc_codegen_llvm/back/link.rs
index d50a56a..8248385 100644
--- a/src/librustc_codegen_llvm/back/link.rs
+++ b/src/librustc_codegen_llvm/back/link.rs
@@ -1666,7 +1666,6 @@
fn are_upstream_rust_objects_already_included(sess: &Session) -> bool {
match sess.lto() {
- Lto::Yes |
Lto::Fat => true,
Lto::Thin => {
// If we defer LTO to the linker, we haven't run LTO ourselves, so
diff --git a/src/librustc_codegen_llvm/back/linker.rs b/src/librustc_codegen_llvm/back/linker.rs
index ebb229b..95be2d8 100644
--- a/src/librustc_codegen_llvm/back/linker.rs
+++ b/src/librustc_codegen_llvm/back/linker.rs
@@ -205,13 +205,12 @@
self.linker_arg(&format!("-plugin-opt={}", opt_level));
self.linker_arg(&format!("-plugin-opt=mcpu={}", llvm_util::target_cpu(self.sess)));
- match self.sess.opts.cg.lto {
+ match self.sess.lto() {
config::Lto::Thin |
config::Lto::ThinLocal => {
self.linker_arg("-plugin-opt=thin");
}
config::Lto::Fat |
- config::Lto::Yes |
config::Lto::No => {
// default to regular LTO
}
diff --git a/src/librustc_codegen_llvm/back/lto.rs b/src/librustc_codegen_llvm/back/lto.rs
index c1dda02..d852eb0 100644
--- a/src/librustc_codegen_llvm/back/lto.rs
+++ b/src/librustc_codegen_llvm/back/lto.rs
@@ -118,7 +118,7 @@
Lto::ThinLocal => SymbolExportLevel::Rust,
// We're doing LTO for the entire crate graph
- Lto::Yes | Lto::Fat | Lto::Thin => {
+ Lto::Fat | Lto::Thin => {
symbol_export::crates_export_threshold(&cgcx.crate_types)
}
@@ -201,7 +201,6 @@
.map(|c| c.as_ptr())
.collect::<Vec<_>>();
match cgcx.lto {
- Lto::Yes | // `-C lto` == fat LTO by default
Lto::Fat => {
assert!(cached_modules.is_empty());
let opt_jobs = fat_lto(cgcx,
diff --git a/src/librustc_codegen_llvm/back/write.rs b/src/librustc_codegen_llvm/back/write.rs
index 1c0f891..3940673 100644
--- a/src/librustc_codegen_llvm/back/write.rs
+++ b/src/librustc_codegen_llvm/back/write.rs
@@ -928,7 +928,6 @@
}
match sess.lto() {
- Lto::Yes |
Lto::Fat |
Lto::No => false,
Lto::Thin |
@@ -1363,7 +1362,7 @@
// require LTO so the request for LTO is always unconditionally
// passed down to the backend, but we don't actually want to do
// anything about it yet until we've got a final product.
- Lto::Yes | Lto::Fat | Lto::Thin => {
+ Lto::Fat | Lto::Thin => {
cgcx.crate_types.len() != 1 ||
cgcx.crate_types[0] != config::CrateType::Rlib
}
@@ -1543,7 +1542,7 @@
exported_symbols.insert(LOCAL_CRATE, copy_symbols(LOCAL_CRATE));
Some(Arc::new(exported_symbols))
}
- Lto::Yes | Lto::Fat | Lto::Thin => {
+ Lto::Fat | Lto::Thin => {
exported_symbols.insert(LOCAL_CRATE, copy_symbols(LOCAL_CRATE));
for &cnum in tcx.crates().iter() {
exported_symbols.insert(cnum, copy_symbols(cnum));
diff --git a/src/test/run-make-fulldeps/codegen-options-parsing/Makefile b/src/test/run-make-fulldeps/codegen-options-parsing/Makefile
index fda96a8..39e9a9b 100644
--- a/src/test/run-make-fulldeps/codegen-options-parsing/Makefile
+++ b/src/test/run-make-fulldeps/codegen-options-parsing/Makefile
@@ -16,11 +16,11 @@
$(RUSTC) -C extra-filename=foo dummy.rs 2>&1
#Option taking no argument
$(RUSTC) -C lto= dummy.rs 2>&1 | \
- $(CGREP) 'codegen option `lto` - one of `thin`, `fat`, or'
+ $(CGREP) 'codegen option `lto` - either a boolean (`yes`, `no`, `on`, `off`, etc), `thin`, `fat`, or omitted'
$(RUSTC) -C lto=1 dummy.rs 2>&1 | \
- $(CGREP) 'codegen option `lto` - one of `thin`, `fat`, or'
+ $(CGREP) 'codegen option `lto` - either a boolean (`yes`, `no`, `on`, `off`, etc), `thin`, `fat`, or omitted'
$(RUSTC) -C lto=foo dummy.rs 2>&1 | \
- $(CGREP) 'codegen option `lto` - one of `thin`, `fat`, or'
+ $(CGREP) 'codegen option `lto` - either a boolean (`yes`, `no`, `on`, `off`, etc), `thin`, `fat`, or omitted'
$(RUSTC) -C lto dummy.rs
# Should not link dead code...
diff --git a/src/test/run-make-fulldeps/lto-smoke/Makefile b/src/test/run-make-fulldeps/lto-smoke/Makefile
index 020252e..9b1dc25 100644
--- a/src/test/run-make-fulldeps/lto-smoke/Makefile
+++ b/src/test/run-make-fulldeps/lto-smoke/Makefile
@@ -1,6 +1,30 @@
-include ../tools.mk
-all:
+all: noparam bool_true bool_false thin fat
+
+noparam:
$(RUSTC) lib.rs
$(RUSTC) main.rs -C lto
$(call RUN,main)
+
+bool_true:
+ $(RUSTC) lib.rs
+ $(RUSTC) main.rs -C lto=yes
+ $(call RUN,main)
+
+
+bool_false:
+ $(RUSTC) lib.rs
+ $(RUSTC) main.rs -C lto=off
+ $(call RUN,main)
+
+thin:
+ $(RUSTC) lib.rs
+ $(RUSTC) main.rs -C lto=thin
+ $(call RUN,main)
+
+fat:
+ $(RUSTC) lib.rs
+ $(RUSTC) main.rs -C lto=fat
+ $(call RUN,main)
+
