clang-cl: Support /P and /E (preprocess to file or stdout)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@197827 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Driver/CLCompatOptions.td

@@ -57,6 +57,7 @@ def _SLASH_C : CLFlag<"C">, HelpText<"Don't discard comments when preprocessing"
 def _SLASH_c : CLFlag<"c">, HelpText<"Compile only">, Alias<c>;
 def _SLASH_D : CLJoinedOrSeparate<"D">, HelpText<"Define macro">,
   MetaVarName<"<macro[=value]>">, Alias<D>;
+def _SLASH_E : CLFlag<"E">, HelpText<"Preprocess to stdout">, Alias<E>;
 def _SLASH_GR : CLFlag<"GR">, HelpText<"Enable RTTI">, Alias<frtti>;
 def _SLASH_GR_ : CLFlag<"GR-">, HelpText<"Disable RTTI">, Alias<fno_rtti>;
 def _SLASH_GF_ : CLFlag<"GF-">, HelpText<"Disable string pooling">,
@@ -88,7 +89,6 @@ def _SLASH_Oy : CLFlag<"Oy">, HelpText<"Enable frame pointer omission">,
   Alias<fomit_frame_pointer>;
 def _SLASH_Oy_ : CLFlag<"Oy-">, HelpText<"Disable frame pointer omission">,
   Alias<fno_omit_frame_pointer>;
-def _SLASH_P : CLFlag<"P">, HelpText<"Only run the preprocessor">, Alias<E>;
 def _SLASH_QUESTION : CLFlag<"?">, Alias<help>,
   HelpText<"Display available options">;
 def _SLASH_showIncludes : CLFlag<"showIncludes">,
@@ -142,6 +142,7 @@ def _SLASH_MT : Option<["/", "-"], "MT", KIND_FLAG>, Group<_SLASH_M_Group>,
   Flags<[CLOption, DriverOption]>, HelpText<"Use static run-time">;
 def _SLASH_MTd : Option<["/", "-"], "MTd", KIND_FLAG>, Group<_SLASH_M_Group>,
   Flags<[CLOption, DriverOption]>, HelpText<"Use static debug run-time">;
+def _SLASH_P : CLFlag<"P">, HelpText<"Preprocess to file">;
 def _SLASH_Tc : CLCompileJoinedOrSeparate<"Tc">,
   HelpText<"Specify a C source file">, MetaVarName<"<filename>">;
 def _SLASH_TC : CLCompileFlag<"TC">, HelpText<"Treat all source files as C">;
@@ -178,7 +179,6 @@ def _SLASH_arch : CLJoined<"arch:">;
 def _SLASH_bigobj : CLFlag<"bigobj">;
 def _SLASH_clr : CLJoined<"clr">;
 def _SLASH_doc : CLJoined<"doc">;
-def _SLASH_E : CLFlag<"E">;
 def _SLASH_EH : CLJoined<"EH">;
 def _SLASH_EP : CLFlag<"EP">;
 def _SLASH_FA_joined : CLJoined<"FA">;

lib/Driver/Driver.cpp

@@ -159,10 +159,11 @@ const {
   Arg *PhaseArg = 0;
   phases::ID FinalPhase;
 
-  // -{E,M,MM} only run the preprocessor.
+  // -{E,M,MM} and /P only run the preprocessor.
   if (CCCIsCPP() ||
       (PhaseArg = DAL.getLastArg(options::OPT_E)) ||
-      (PhaseArg = DAL.getLastArg(options::OPT_M, options::OPT_MM))) {
+      (PhaseArg = DAL.getLastArg(options::OPT_M, options::OPT_MM)) ||
+      (PhaseArg = DAL.getLastArg(options::OPT__SLASH_P))) {
     FinalPhase = phases::Preprocess;
 
     // -{fsyntax-only,-analyze,emit-ast,S} only run up to the compiler.
@@ -1627,6 +1628,14 @@ const char *Driver::GetNamedOutputPath(Compilation &C,
       return C.addResultFile(FinalOutput->getValue(), &JA);
   }
 
+  // For /P, preprocess to file named after BaseInput.
+  if (C.getArgs().hasArg(options::OPT__SLASH_P)) {
+    assert(AtTopLevel && isa<PreprocessJobAction>(JA));
+    StringRef BaseName = llvm::sys::path::filename(BaseInput);
+    return C.addResultFile(MakeCLOutputFilename(C.getArgs(), "", BaseName,
+                                                types::TY_PP_C), &JA);
+  }
+
   // Default to writing to stdout?
   if (AtTopLevel && !CCGenDiagnostics &&
       (isa<PreprocessJobAction>(JA) || JA.getType() == types::TY_ModuleFile))

test/Driver/cl-options.c

@@ -14,6 +14,10 @@
 // RUN: %clang_cl /D foo=bar -### -- %s 2>&1 | FileCheck -check-prefix=D %s
 // D: "-D" "foo=bar"
 
+// RUN: %clang_cl /E -### -- %s 2>&1 | FileCheck -check-prefix=E %s
+// E: "-E"
+// E: "-o" "-"
+
 // RTTI is on by default; just check that we don't error.
 // RUN: %clang_cl /Zs /GR -- %s 2>&1
 
@@ -56,9 +60,6 @@
 // RUN: %clang_cl /Oy- -### -- %s 2>&1 | FileCheck -check-prefix=Oy_ %s
 // Oy_: -mdisable-fp-elim
 
-// RUN: %clang_cl /P -### -- %s 2>&1 | FileCheck -check-prefix=P %s
-// P: -E
-
 // RUN: %clang_cl /showIncludes -### -- %s 2>&1 | FileCheck -check-prefix=showIncludes %s
 // showIncludes: --show-includes
 
@@ -140,7 +141,6 @@
 // RUN:     /arch:sse2 \
 // RUN:     /clr:pure \
 // RUN:     /docname \
-// RUN:     /E \
 // RUN:     /EHsc \
 // RUN:     /EP \
 // RUN:     /F \

test/Driver/cl-outputs.c

@@ -105,3 +105,7 @@
 // FaDIRNAMEEXT:  "-o" "foo.dir{{[/\\]+}}a.ext"
 // RUN: %clang_cl /Faa.asm -### -- %s %s 2>&1 | FileCheck -check-prefix=FaMULTIPLESOURCE %s
 // FaMULTIPLESOURCE: error: cannot specify '/Faa.asm' when compiling multiple source files
+
+// RUN: %clang_cl /P -### -- %s 2>&1 | FileCheck -check-prefix=P %s
+// P: "-E"
+// P: "-o" "cl-outputs.i"