Make -O mean -C opt-level=3

compiler/rustc_codegen_cranelift/src/lib.rs

@@ -289,7 +289,7 @@ fn build_isa(sess: &Session) -> Arc<dyn TargetIsa + 'static> {
             flags_builder.set("opt_level", "none").unwrap();
         }
         OptLevel::Less
-        | OptLevel::Default
+        | OptLevel::More
         | OptLevel::Size
         | OptLevel::SizeMin
         | OptLevel::Aggressive => {

compiler/rustc_codegen_gcc/src/lib.rs

@@ -476,7 +476,7 @@ fn to_gcc_opt_level(optlevel: Option<OptLevel>) -> OptimizationLevel {
         Some(level) => match level {
             OptLevel::No => OptimizationLevel::None,
             OptLevel::Less => OptimizationLevel::Limited,
-            OptLevel::Default => OptimizationLevel::Standard,
+            OptLevel::More => OptimizationLevel::Standard,
             OptLevel::Aggressive => OptimizationLevel::Aggressive,
             OptLevel::Size | OptLevel::SizeMin => OptimizationLevel::Limited,
         },

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -141,7 +141,7 @@ fn to_llvm_opt_settings(cfg: config::OptLevel) -> (llvm::CodeGenOptLevel, llvm::
     match cfg {
         No => (llvm::CodeGenOptLevel::None, llvm::CodeGenOptSizeNone),
         Less => (llvm::CodeGenOptLevel::Less, llvm::CodeGenOptSizeNone),
-        Default => (llvm::CodeGenOptLevel::Default, llvm::CodeGenOptSizeNone),
+        More => (llvm::CodeGenOptLevel::Default, llvm::CodeGenOptSizeNone),
         Aggressive => (llvm::CodeGenOptLevel::Aggressive, llvm::CodeGenOptSizeNone),
         Size => (llvm::CodeGenOptLevel::Default, llvm::CodeGenOptSizeDefault),
         SizeMin => (llvm::CodeGenOptLevel::Default, llvm::CodeGenOptSizeAggressive),
@@ -153,7 +153,7 @@ fn to_pass_builder_opt_level(cfg: config::OptLevel) -> llvm::PassBuilderOptLevel
     match cfg {
         No => llvm::PassBuilderOptLevel::O0,
         Less => llvm::PassBuilderOptLevel::O1,
-        Default => llvm::PassBuilderOptLevel::O2,
+        More => llvm::PassBuilderOptLevel::O2,
         Aggressive => llvm::PassBuilderOptLevel::O3,
         Size => llvm::PassBuilderOptLevel::Os,
         SizeMin => llvm::PassBuilderOptLevel::Oz,

compiler/rustc_codegen_ssa/src/back/linker.rs

@@ -410,7 +410,7 @@ impl<'a> GccLinker<'a> {
         let opt_level = match self.sess.opts.optimize {
             config::OptLevel::No => "O0",
             config::OptLevel::Less => "O1",
-            config::OptLevel::Default | config::OptLevel::Size | config::OptLevel::SizeMin => "O2",
+            config::OptLevel::More | config::OptLevel::Size | config::OptLevel::SizeMin => "O2",
             config::OptLevel::Aggressive => "O3",
         };
 
@@ -685,7 +685,7 @@ impl<'a> Linker for GccLinker<'a> {
 
         // GNU-style linkers support optimization with -O. GNU ld doesn't
         // need a numeric argument, but other linkers do.
-        if self.sess.opts.optimize == config::OptLevel::Default
+        if self.sess.opts.optimize == config::OptLevel::More
             || self.sess.opts.optimize == config::OptLevel::Aggressive
         {
             self.link_arg("-O1");
@@ -1213,7 +1213,7 @@ impl<'a> Linker for EmLinker<'a> {
         self.cc_arg(match self.sess.opts.optimize {
             OptLevel::No => "-O0",
             OptLevel::Less => "-O1",
-            OptLevel::Default => "-O2",
+            OptLevel::More => "-O2",
             OptLevel::Aggressive => "-O3",
             OptLevel::Size => "-Os",
             OptLevel::SizeMin => "-Oz",
@@ -1384,7 +1384,7 @@ impl<'a> Linker for WasmLd<'a> {
         self.link_arg(match self.sess.opts.optimize {
             OptLevel::No => "-O0",
             OptLevel::Less => "-O1",
-            OptLevel::Default => "-O2",
+            OptLevel::More => "-O2",
             OptLevel::Aggressive => "-O3",
             // Currently LLD doesn't support `Os` and `Oz`, so pass through `O2`
             // instead.
@@ -1451,7 +1451,7 @@ impl<'a> WasmLd<'a> {
         let opt_level = match self.sess.opts.optimize {
             config::OptLevel::No => "O0",
             config::OptLevel::Less => "O1",
-            config::OptLevel::Default => "O2",
+            config::OptLevel::More => "O2",
             config::OptLevel::Aggressive => "O3",
             // wasm-ld only handles integer LTO opt levels. Use O2
             config::OptLevel::Size | config::OptLevel::SizeMin => "O2",
@@ -1525,7 +1525,7 @@ impl<'a> Linker for L4Bender<'a> {
     fn optimize(&mut self) {
         // GNU-style linkers support optimization with -O. GNU ld doesn't
         // need a numeric argument, but other linkers do.
-        if self.sess.opts.optimize == config::OptLevel::Default
+        if self.sess.opts.optimize == config::OptLevel::More
             || self.sess.opts.optimize == config::OptLevel::Aggressive
         {
             self.link_arg("-O1");
@@ -1929,7 +1929,7 @@ impl<'a> Linker for LlbcLinker<'a> {
         match self.sess.opts.optimize {
             OptLevel::No => "-O0",
             OptLevel::Less => "-O1",
-            OptLevel::Default => "-O2",
+            OptLevel::More => "-O2",
             OptLevel::Aggressive => "-O3",
             OptLevel::Size => "-Os",
             OptLevel::SizeMin => "-Oz",
@@ -2006,7 +2006,7 @@ impl<'a> Linker for BpfLinker<'a> {
         self.link_arg(match self.sess.opts.optimize {
             OptLevel::No => "-O0",
             OptLevel::Less => "-O1",
-            OptLevel::Default => "-O2",
+            OptLevel::More => "-O2",
             OptLevel::Aggressive => "-O3",
             OptLevel::Size => "-Os",
             OptLevel::SizeMin => "-Oz",

compiler/rustc_codegen_ssa/src/back/write.rs

@@ -236,7 +236,7 @@ impl ModuleConfig {
             // Copy what clang does by turning on loop vectorization at O2 and
             // slp vectorization at O3.
             vectorize_loop: !sess.opts.cg.no_vectorize_loops
-                && (sess.opts.optimize == config::OptLevel::Default
+                && (sess.opts.optimize == config::OptLevel::More
                     || sess.opts.optimize == config::OptLevel::Aggressive),
             vectorize_slp: !sess.opts.cg.no_vectorize_slp
                 && sess.opts.optimize == config::OptLevel::Aggressive,
@@ -260,7 +260,7 @@ impl ModuleConfig {
                 MergeFunctions::Trampolines | MergeFunctions::Aliases => {
                     use config::OptLevel::*;
                     match sess.opts.optimize {
-                        Aggressive | Default | SizeMin | Size => true,
+                        Aggressive | More | SizeMin | Size => true,
                         Less | No => false,
                     }
                 }

compiler/rustc_codegen_ssa/src/base.rs

@@ -1054,12 +1054,12 @@ pub(crate) fn provide(providers: &mut Providers) {
             config::OptLevel::No => return config::OptLevel::No,
             // If globally optimise-speed is already specified, just use that level.
             config::OptLevel::Less => return config::OptLevel::Less,
-            config::OptLevel::Default => return config::OptLevel::Default,
+            config::OptLevel::More => return config::OptLevel::More,
             config::OptLevel::Aggressive => return config::OptLevel::Aggressive,
             // If globally optimize-for-size has been requested, use -O2 instead (if optimize(size)
             // are present).
-            config::OptLevel::Size => config::OptLevel::Default,
+            config::OptLevel::Size => config::OptLevel::More,
-            config::OptLevel::SizeMin => config::OptLevel::Default,
+            config::OptLevel::SizeMin => config::OptLevel::More,
         };
 
         let defids = tcx.collect_and_partition_mono_items(cratenum).all_mono_items;

compiler/rustc_mir_transform/src/inline.rs

@@ -49,8 +49,7 @@ impl<'tcx> crate::MirPass<'tcx> for Inline {
         match sess.mir_opt_level() {
             0 | 1 => false,
             2 => {
-                (sess.opts.optimize == OptLevel::Default
+                (sess.opts.optimize == OptLevel::More || sess.opts.optimize == OptLevel::Aggressive)
-                    || sess.opts.optimize == OptLevel::Aggressive)
                     && sess.opts.incremental == None
             }
             _ => true,

compiler/rustc_session/src/config.rs

@@ -86,12 +86,18 @@ pub enum CFProtection {
 
 #[derive(Clone, Copy, Debug, PartialEq, Hash, HashStable_Generic)]
 pub enum OptLevel {
-    No,         // -O0
+    /// `-Copt-level=0`
-    Less,       // -O1
+    No,
-    Default,    // -O2
+    /// `-Copt-level=1`
-    Aggressive, // -O3
+    Less,
-    Size,       // -Os
+    /// `-Copt-level=2`
-    SizeMin,    // -Oz
+    More,
+    /// `-Copt-level=3` / `-O`
+    Aggressive,
+    /// `-Copt-level=s`
+    Size,
+    /// `-Copt-level=z`
+    SizeMin,
 }
 
 /// This is what the `LtoCli` values get mapped to after resolving defaults and
@@ -1253,7 +1259,7 @@ impl Options {
             Some(setting) => setting,
             None => match self.optimize {
                 OptLevel::No | OptLevel::Less | OptLevel::Size | OptLevel::SizeMin => true,
-                OptLevel::Default | OptLevel::Aggressive => false,
+                OptLevel::More | OptLevel::Aggressive => false,
             },
         }
     }
@@ -1572,7 +1578,7 @@ pub fn rustc_optgroups() -> Vec<RustcOptGroup> {
              stack-protector-strategies|link-args|deployment-target]",
         ),
         opt(Stable, FlagMulti, "g", "", "Equivalent to -C debuginfo=2", ""),
-        opt(Stable, FlagMulti, "O", "", "Equivalent to -C opt-level=2", ""),
+        opt(Stable, FlagMulti, "O", "", "Equivalent to -C opt-level=3", ""),
         opt(Stable, Opt, "o", "", "Write output to <filename>", "FILENAME"),
         opt(Stable, Opt, "", "out-dir", "Write output to compiler-chosen filename in <dir>", "DIR"),
         opt(
@@ -2127,12 +2133,12 @@ fn parse_opt_level(
         })
         .max();
     if max_o > max_c {
-        OptLevel::Default
+        OptLevel::Aggressive
     } else {
         match cg.opt_level.as_ref() {
             "0" => OptLevel::No,
             "1" => OptLevel::Less,
-            "2" => OptLevel::Default,
+            "2" => OptLevel::More,
             "3" => OptLevel::Aggressive,
             "s" => OptLevel::Size,
             "z" => OptLevel::SizeMin,

src/doc/rustc/src/codegen-options/index.md

@@ -368,7 +368,7 @@ This flag controls the optimization level.
 * `s`: optimize for binary size.
 * `z`: optimize for binary size, but also turn off loop vectorization.
 
-Note: The [`-O` flag][option-o-optimize] is an alias for `-C opt-level=2`.
+Note: The [`-O` flag][option-o-optimize] is an alias for `-C opt-level=3`.
 
 The default is `0`.
 

src/doc/rustc/src/command-line-arguments.md

@@ -308,7 +308,7 @@ A synonym for [`-C debuginfo=2`](codegen-options/index.md#debuginfo).
 <a id="option-o-optimize"></a>
 ## `-O`: optimize your code
 
-A synonym for [`-C opt-level=2`](codegen-options/index.md#opt-level).
+A synonym for [`-C opt-level=3`](codegen-options/index.md#opt-level).
 
 <a id="option-o-output"></a>
 ## `-o`: filename of the output

src/tools/run-make-support/src/external_deps/rustc.rs

@@ -84,7 +84,7 @@ impl Rustc {
         self
     }
 
-    /// Specify default optimization level `-O` (alias for `-C opt-level=2`).
+    /// Specify default optimization level `-O` (alias for `-C opt-level=3`).
     pub fn opt(&mut self) -> &mut Self {
         self.cmd.arg("-O");
         self

tests/run-make/rustc-help/help-v.stdout

@@ -32,7 +32,7 @@ Options:
         --print [crate-name|file-names|sysroot|target-libdir|cfg|check-cfg|calling-conventions|target-list|target-cpus|target-features|relocation-models|code-models|tls-models|target-spec-json|all-target-specs-json|native-static-libs|stack-protector-strategies|link-args|deployment-target]
                         Compiler information to print on stdout
     -g                  Equivalent to -C debuginfo=2
-    -O                  Equivalent to -C opt-level=2
+    -O                  Equivalent to -C opt-level=3
     -o FILENAME         Write output to <filename>
         --out-dir DIR   Write output to compiler-chosen filename in <dir>
         --explain OPT   Provide a detailed explanation of an error message

tests/run-make/rustc-help/help.stdout

@@ -32,7 +32,7 @@ Options:
         --print [crate-name|file-names|sysroot|target-libdir|cfg|check-cfg|calling-conventions|target-list|target-cpus|target-features|relocation-models|code-models|tls-models|target-spec-json|all-target-specs-json|native-static-libs|stack-protector-strategies|link-args|deployment-target]
                         Compiler information to print on stdout
     -g                  Equivalent to -C debuginfo=2
-    -O                  Equivalent to -C opt-level=2
+    -O                  Equivalent to -C opt-level=3
     -o FILENAME         Write output to <filename>
         --out-dir DIR   Write output to compiler-chosen filename in <dir>
         --explain OPT   Provide a detailed explanation of an error message