ccc: Introduce ToolChains for mapping Actions to Tools which can
perform them.

 - A ToolChain is a coherent set of tools use in a compilation
   process. The idea is that a ToolChain holds roughly the information
   (specs, search paths, etc.) that is in a single gcc binary.

 - The default ToolChain is selected by the host and will generally
   correspond to what the default system compiler would do. However,
   this can be over-riden for a variety of purposes, for example the
   by the driver driver or for testing.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62021 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/ccc/ccclib/ToolChain.py b/tools/ccc/ccclib/ToolChain.py
new file mode 100644
index 0000000..46146b5
--- /dev/null
+++ b/tools/ccc/ccclib/ToolChain.py
@@ -0,0 +1,50 @@
+import Phases
+import Tools
+
+###
+
+class ToolChain(object):
+    """ToolChain - Provide mappings of Actions to Tools."""
+
+    def __init__(self, driver):
+        self.driver = driver
+
+    def selectTool(self, action):
+        """selectTool - Return a Tool instance to use for handling
+        some particular action."""
+        abstract
+
+class Darwin_ToolChain(ToolChain):
+    def __init__(self, driver):
+        super(Darwin_ToolChain, self).__init__(driver)
+        self.toolMap = {
+            Phases.PreprocessPhase : Tools.GCC_PreprocessTool(),
+            Phases.CompilePhase : Tools.GCC_CompileTool(),
+            Phases.PrecompilePhase : Tools.GCC_PrecompileTool(),
+            Phases.AssemblePhase : Tools.DarwinAssembleTool(),
+            Phases.LinkPhase : Tools.Collect2Tool(),
+            Phases.LipoPhase : Tools.LipoTool(),
+            }
+
+    def selectTool(self, action):
+        assert isinstance(action, Phases.JobAction)
+        return self.toolMap[action.phase.__class__]
+
+class Generic_GCC_ToolChain(ToolChain):
+    """Generic_GCC_ToolChain - A tool chain using the 'gcc' command to
+    perform all subcommands; this relies on gcc translating the
+    options appropriately."""
+
+    def __init__(self, driver):
+        super(Generic_GCC_ToolChain, self).__init__(driver)
+        self.toolMap = {
+            Phases.PreprocessPhase : Tools.GCC_PreprocessTool(),
+            Phases.CompilePhase : Tools.GCC_CompileTool(),
+            Phases.PrecompilePhase : Tools.GCC_PrecompileTool(),
+            Phases.AssemblePhase : Tools.GCC_AssembleTool(),
+            Phases.LinkPhase : Tools.GCC_LinkTool(),
+            }
+
+    def selectTool(self, action):
+        assert isinstance(action, Phases.JobAction)
+        return self.toolMap[action.phase.__class__]