[Driver] Allow for -O3 on Windows using clang-cl (#12504)

We currently support -O3 for Linux compilations, expand this to also be available on Windows. This also better aligns with our existing product offerings.
intel · Feb 1, 2024 · 0af4ac7 · 0af4ac7
1 parent f7a360d
commit 0af4ac7
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Showing 4 changed files with 20 additions and 8 deletions.
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
@@ -8404,6 +8404,9 @@ def : CLFlag<"O1">, Alias<_SLASH_O>, AliasArgs<["1"]>,
  HelpText<"Optimize for size (like /Og /Os /Oy /Ob2 /GF /Gy)">;
 def : CLFlag<"O2">, Alias<_SLASH_O>, AliasArgs<["2"]>,
  HelpText<"Optimize for speed (like /Og /Oi /Ot /Oy /Ob2 /GF /Gy)">;
+def : CLFlag<"O3">, Alias<_SLASH_O>, AliasArgs<["3"]>,
+ HelpText<"Optimize for maximum speed and enable more aggressive optimizations"
+ " that may not improve performance on some programs">;
 def : CLFlag<"Ob0">, Alias<_SLASH_O>, AliasArgs<["b0"]>,
  HelpText<"Disable function inlining">;
 def : CLFlag<"Ob1">, Alias<_SLASH_O>, AliasArgs<["b1"]>,

diff --git a/clang/lib/Driver/ToolChains/MSVC.cpp b/clang/lib/Driver/ToolChains/MSVC.cpp
@@ -930,6 +930,7 @@ static void TranslateOptArg(Arg *A, llvm::opt::DerivedArgList &DAL,
  break;
  case '1':
  case '2':
+ case '3':
  case 'x':
  case 'd':
  // Ignore /O[12xd] flags that aren't the last one on the command line.
@@ -946,11 +947,14 @@ static void TranslateOptArg(Arg *A, llvm::opt::DerivedArgList &DAL,
  } else if (OptChar == '2' || OptChar == 'x') {
  DAL.AddFlagArg(A, Opts.getOption(options::OPT_fbuiltin));
  DAL.AddJoinedArg(A, Opts.getOption(options::OPT_O), "2");
+ } else if (OptChar == '3') {
+ DAL.AddFlagArg(A, Opts.getOption(options::OPT_fbuiltin));
+ DAL.AddJoinedArg(A, Opts.getOption(options::OPT_O), "3");
  }
  if (SupportsForcingFramePointer &&
  !DAL.hasArgNoClaim(options::OPT_fno_omit_frame_pointer))
  DAL.AddFlagArg(A, Opts.getOption(options::OPT_fomit_frame_pointer));
- if (OptChar == '1' || OptChar == '2')
+ if (OptChar == '1' || OptChar == '2' || OptChar == '3')
  DAL.AddFlagArg(A, Opts.getOption(options::OPT_ffunction_sections));
  }
  break;
@@ -1070,7 +1074,8 @@ MSVCToolChain::TranslateArgs(const llvm::opt::DerivedArgList &Args,
  // OptChar does not expand; it's an argument to the previous char.
  continue;
  }
- if (OptChar == '1' || OptChar == '2' || OptChar == 'x' || OptChar == 'd')
+ if (OptChar == '1' || OptChar == '2' || OptChar == 'x' ||
+ OptChar == 'd' || OptChar == '3')
  ExpandChar = OptStr.data() + I;
  }
  }

diff --git a/clang/test/Driver/Xarch.c b/clang/test/Driver/Xarch.c
@@ -1,10 +1,10 @@
-// RUN: %clang -target i386-apple-darwin11 -m32 -Xarch_i386 -O3 %s -S -### 2>&1 | FileCheck -check-prefix=O3ONCE %s
-// O3ONCE: "-O3"
-// O3ONCE-NOT: "-O3"
+// RUN: %clang -target i386-apple-darwin11 -m32 -Xarch_i386 -O5 %s -S -### 2>&1 | FileCheck -check-prefix=O5ONCE %s
+// O5ONCE: "-O5"
+// O5ONCE-NOT: "-O5"
 
-// RUN: %clang -target i386-apple-darwin11 -m64 -Xarch_i386 -O3 %s -S -### 2>&1 | FileCheck -check-prefix=O3NONE %s
-// O3NONE-NOT: "-O3"
-// O3NONE: argument unused during compilation: '-Xarch_i386 -O3'
+// RUN: %clang -target i386-apple-darwin11 -m64 -Xarch_i386 -O5 %s -S -### 2>&1 | FileCheck -check-prefix=O5NONE %s
+// O5NONE-NOT: "-O5"
+// O5NONE: argument unused during compilation: '-Xarch_i386 -O5'
 
 // RUN: not %clang -target i386-apple-darwin11 -m32 -Xarch_i386 -o -Xarch_i386 -S %s -S -Xarch_i386 -o 2>&1 | FileCheck -check-prefix=INVALID %s
 // INVALID: error: invalid Xarch argument: '-Xarch_i386 -o'

diff --git a/clang/test/Driver/cl-options.c b/clang/test/Driver/cl-options.c
@@ -207,6 +207,10 @@
 // RUN: %clang_cl --target=i686-pc-win32 -Werror -Wno-msvc-not-found /O2 /O2 -### -- %s 2>&1 | FileCheck -check-prefix=O2O2 %s
 // O2O2: "-O2"
 
+// RUN: %clang_cl --target=i686-pc-win32 -Werror -Wno-msvc-not-found /O3 -### -- %s 2>&1 | FileCheck -check-prefix=O3 %s
+// O3: -mframe-pointer=none
+// O3: -O3
+
 // RUN: %clang_cl /Zs -Werror /Oy -- %s 2>&1
 
 // RUN: %clang_cl --target=i686-pc-win32 -Werror -Wno-msvc-not-found /Oy- -### -- %s 2>&1 | FileCheck -check-prefix=Oy_ %s