[clang][NFC] Consolidating usage of "FinalPhase" in Driver::BuildActions.

I am working to remove this concept of the "FinalPhase" in the clang driver,
but it is used in a lot of different places to do argument handling for
different combinations of phase pipelines and arguments. I am trying to
consolidate most of the uses of "FinalPhase" into its own separate scope.
Eventually, in a subsequent patch I will move all of this stuff to a separate
function, and have more of the complication phase list construction setup into
types::getComplicationPhases.

Differential Revision: https://reviews.llvm.org/D65969




git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@368393 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Driver/Driver.cpp

@@ -3157,17 +3157,6 @@ void Driver::BuildActions(Compilation &C, DerivedArgList &Args,
     return;
   }
 
-  Arg *FinalPhaseArg;
-  phases::ID FinalPhase = getFinalPhase(Args, &FinalPhaseArg);
-
-  if (FinalPhase == phases::Link) {
-    if (Args.hasArg(options::OPT_emit_llvm))
-      Diag(clang::diag::err_drv_emit_llvm_link);
-    if (IsCLMode() && LTOMode != LTOK_None &&
-        !Args.getLastArgValue(options::OPT_fuse_ld_EQ).equals_lower("lld"))
-      Diag(clang::diag::err_drv_lto_without_lld);
-  }
-
   // Reject -Z* at the top level, these options should never have been exposed
   // by gcc.
   if (Arg *A = Args.getLastArg(options::OPT_Z_Joined))
@@ -3220,15 +3209,6 @@ void Driver::BuildActions(Compilation &C, DerivedArgList &Args,
     Args.eraseArg(options::OPT__SLASH_Yc);
     YcArg = nullptr;
   }
-  if (FinalPhase == phases::Preprocess || Args.hasArg(options::OPT__SLASH_Y_)) {
-    // If only preprocessing or /Y- is used, all pch handling is disabled.
-    // Rather than check for it everywhere, just remove clang-cl pch-related
-    // flags here.
-    Args.eraseArg(options::OPT__SLASH_Fp);
-    Args.eraseArg(options::OPT__SLASH_Yc);
-    Args.eraseArg(options::OPT__SLASH_Yu);
-    YcArg = YuArg = nullptr;
-  }
 
   // Builder to be used to build offloading actions.
   OffloadingActionBuilder OffloadBuilder(C, Args, Inputs);
@@ -3237,70 +3217,115 @@ void Driver::BuildActions(Compilation &C, DerivedArgList &Args,
   HeaderModulePrecompileJobAction *HeaderModuleAction = nullptr;
   ActionList LinkerInputs;
 
-  unsigned LastPLSize = 0;
-  for (auto &I : Inputs) {
-    types::ID InputType = I.first;
-    const Arg *InputArg = I.second;
+  phases::ID FinalPhase;
+  {
+    Arg *FinalPhaseArg;
+    FinalPhase = getFinalPhase(Args, &FinalPhaseArg);
+
+    if (FinalPhase == phases::Link) {
+      if (Args.hasArg(options::OPT_emit_llvm))
+        Diag(clang::diag::err_drv_emit_llvm_link);
+      if (IsCLMode() && LTOMode != LTOK_None &&
+          !Args.getLastArgValue(options::OPT_fuse_ld_EQ).equals_lower("lld"))
+        Diag(clang::diag::err_drv_lto_without_lld);
+    }
 
-    llvm::SmallVector<phases::ID, phases::MaxNumberOfPhases> PL;
-    types::getCompilationPhases(InputType, PL);
-    LastPLSize = PL.size();
+    if (FinalPhase == phases::Preprocess ||
+        Args.hasArg(options::OPT__SLASH_Y_)) {
+      // If only preprocessing or /Y- is used, all pch handling is disabled.
+      // Rather than check for it everywhere, just remove clang-cl pch-related
+      // flags here.
+      Args.eraseArg(options::OPT__SLASH_Fp);
+      Args.eraseArg(options::OPT__SLASH_Yc);
+      Args.eraseArg(options::OPT__SLASH_Yu);
+      YcArg = YuArg = nullptr;
+    }
 
-    // If the first step comes after the final phase we are doing as part of
-    // this compilation, warn the user about it.
-    phases::ID InitialPhase = PL[0];
-    if (InitialPhase > FinalPhase) {
-      if (InputArg->isClaimed())
-        continue;
+    unsigned LastPLSize = 0;
+    for (auto &I : Inputs) {
+      types::ID InputType = I.first;
+      const Arg *InputArg = I.second;
+
+      llvm::SmallVector<phases::ID, phases::MaxNumberOfPhases> PL;
+      types::getCompilationPhases(InputType, PL);
+      LastPLSize = PL.size();
 
-      // Claim here to avoid the more general unused warning.
-      InputArg->claim();
+      // If the first step comes after the final phase we are doing as part of
+      // this compilation, warn the user about it.
+      phases::ID InitialPhase = PL[0];
+      if (InitialPhase > FinalPhase) {
+        if (InputArg->isClaimed())
+          continue;
 
-      // Suppress all unused style warnings with -Qunused-arguments
-      if (Args.hasArg(options::OPT_Qunused_arguments))
+        // Claim here to avoid the more general unused warning.
+        InputArg->claim();
+
+        // Suppress all unused style warnings with -Qunused-arguments
+        if (Args.hasArg(options::OPT_Qunused_arguments))
+          continue;
+
+        // Special case when final phase determined by binary name, rather than
+        // by a command-line argument with a corresponding Arg.
+        if (CCCIsCPP())
+          Diag(clang::diag::warn_drv_input_file_unused_by_cpp)
+              << InputArg->getAsString(Args) << getPhaseName(InitialPhase);
+        // Special case '-E' warning on a previously preprocessed file to make
+        // more sense.
+        else if (InitialPhase == phases::Compile &&
+                 (Args.getLastArg(options::OPT__SLASH_EP,
+                                  options::OPT__SLASH_P) ||
+                  Args.getLastArg(options::OPT_E) ||
+                  Args.getLastArg(options::OPT_M, options::OPT_MM)) &&
+                 getPreprocessedType(InputType) == types::TY_INVALID)
+          Diag(clang::diag::warn_drv_preprocessed_input_file_unused)
+              << InputArg->getAsString(Args) << !!FinalPhaseArg
+              << (FinalPhaseArg ? FinalPhaseArg->getOption().getName() : "");
+        else
+          Diag(clang::diag::warn_drv_input_file_unused)
+              << InputArg->getAsString(Args) << getPhaseName(InitialPhase)
+              << !!FinalPhaseArg
+              << (FinalPhaseArg ? FinalPhaseArg->getOption().getName() : "");
         continue;
+      }
 
-      // Special case when final phase determined by binary name, rather than
-      // by a command-line argument with a corresponding Arg.
-      if (CCCIsCPP())
-        Diag(clang::diag::warn_drv_input_file_unused_by_cpp)
-            << InputArg->getAsString(Args) << getPhaseName(InitialPhase);
-      // Special case '-E' warning on a previously preprocessed file to make
-      // more sense.
-      else if (InitialPhase == phases::Compile &&
-               FinalPhase == phases::Preprocess &&
-               getPreprocessedType(InputType) == types::TY_INVALID)
-        Diag(clang::diag::warn_drv_preprocessed_input_file_unused)
-            << InputArg->getAsString(Args) << !!FinalPhaseArg
-            << (FinalPhaseArg ? FinalPhaseArg->getOption().getName() : "");
-      else
-        Diag(clang::diag::warn_drv_input_file_unused)
-            << InputArg->getAsString(Args) << getPhaseName(InitialPhase)
-            << !!FinalPhaseArg
-            << (FinalPhaseArg ? FinalPhaseArg->getOption().getName() : "");
-      continue;
+      if (YcArg) {
+        // Add a separate precompile phase for the compile phase.
+        if (FinalPhase >= phases::Compile) {
+          const types::ID HeaderType = lookupHeaderTypeForSourceType(InputType);
+          llvm::SmallVector<phases::ID, phases::MaxNumberOfPhases> PCHPL;
+          types::getCompilationPhases(HeaderType, PCHPL);
+          // Build the pipeline for the pch file.
+          Action *ClangClPch = C.MakeAction<InputAction>(*InputArg, HeaderType);
+          for (phases::ID Phase : PCHPL)
+            ClangClPch = ConstructPhaseAction(C, Args, Phase, ClangClPch);
+          assert(ClangClPch);
+          Actions.push_back(ClangClPch);
+          // The driver currently exits after the first failed command.  This
+          // relies on that behavior, to make sure if the pch generation fails,
+          // the main compilation won't run.
+          // FIXME: If the main compilation fails, the PCH generation should
+          // probably not be considered successful either.
+        }
+      }
     }
 
-    if (YcArg) {
-      // Add a separate precompile phase for the compile phase.
-      if (FinalPhase >= phases::Compile) {
-        const types::ID HeaderType = lookupHeaderTypeForSourceType(InputType);
-        llvm::SmallVector<phases::ID, phases::MaxNumberOfPhases> PCHPL;
-        types::getCompilationPhases(HeaderType, PCHPL);
-        // Build the pipeline for the pch file.
-        Action *ClangClPch =
-            C.MakeAction<InputAction>(*InputArg, HeaderType);
-        for (phases::ID Phase : PCHPL)
-          ClangClPch = ConstructPhaseAction(C, Args, Phase, ClangClPch);
-        assert(ClangClPch);
-        Actions.push_back(ClangClPch);
-        // The driver currently exits after the first failed command.  This
-        // relies on that behavior, to make sure if the pch generation fails,
-        // the main compilation won't run.
-        // FIXME: If the main compilation fails, the PCH generation should
-        // probably not be considered successful either.
-      }
+    // If we are linking, claim any options which are obviously only used for
+    // compilation.
+    // FIXME: Understand why the last Phase List length is used here.
+    if (FinalPhase == phases::Link && LastPLSize == 1) {
+      Args.ClaimAllArgs(options::OPT_CompileOnly_Group);
+      Args.ClaimAllArgs(options::OPT_cl_compile_Group);
     }
+  }
+
+  for (auto &I : Inputs) {
+    types::ID InputType = I.first;
+    const Arg *InputArg = I.second;
+
+    llvm::SmallVector<phases::ID, phases::MaxNumberOfPhases> PL;
+    types::getCompilationPhases(InputType, PL);
+    if (PL[0] > FinalPhase)
+      continue;
 
     // Build the pipeline for this file.
     Action *Current = C.MakeAction<InputAction>(*InputArg, InputType);
@@ -3379,14 +3404,6 @@ void Driver::BuildActions(Compilation &C, DerivedArgList &Args,
     Actions.push_back(LA);
   }
 
-  // If we are linking, claim any options which are obviously only used for
-  // compilation.
-  // FIXME: Understand why the last Phase List length is used here.
-  if (FinalPhase == phases::Link && LastPLSize == 1) {
-    Args.ClaimAllArgs(options::OPT_CompileOnly_Group);
-    Args.ClaimAllArgs(options::OPT_cl_compile_Group);
-  }
-
   // If --print-supported-cpus, -mcpu=? or -mtune=? is specified, build a custom
   // Compile phase that prints out supported cpu models and quits.
   if (Arg *A = Args.getLastArg(options::OPT_print_supported_cpus)) {