Add some switches helpful for debugging:

-print-before=<Pass Name>

Dump IR before running pass <Pass Name>.

-print-before-all

Dump IR before running each pass.

-print-after-all

Dump IR after running each pass.

These are helpful when tracking down a miscompilation.  It is easy to
get IR dumps and do diffs on them, etc.

To make this work well, add a new getPrinterPass API to Pass so that
each kind of pass (ModulePass, FunctionPass, etc.) can create a Pass
suitable for dumping out the kind of object the Pass works on.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100143 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 15 insertions, 0 deletions

diff --git a/include/llvm/Pass.h b/include/llvm/Pass.h
index 8fc3a53..b9d915d 100644
--- a/include/llvm/Pass.h
+++ b/include/llvm/Pass.h
@@ -30,6 +30,7 @@
 #define LLVM_PASS_H
 
 #include "llvm/System/DataTypes.h"
+
 #include <cassert>
 #include <utility>
 #include <vector>
@@ -120,6 +121,11 @@ public:
   virtual void print(raw_ostream &O, const Module *M) const;
   void dump() const; // dump - Print to stderr.
 
+  /// createPrinterPass - Get a Pass appropriate to print the IR this
+  /// pass operates one (Module, Function or MachineFunction).
+  virtual Pass *createPrinterPass(raw_ostream &O,
+                                  const std::string &Banner) const = 0;
+
   /// Each pass is responsible for assigning a pass manager to itself.
   /// PMS is the stack of available pass manager. 
   virtual void assignPassManager(PMStack &, 
@@ -233,6 +239,9 @@ public:
 ///
 class ModulePass : public Pass {
 public:
+  /// createPrinterPass - Get a module printer pass.
+  Pass *createPrinterPass(raw_ostream &O, const std::string &Banner) const;
+
   /// runOnModule - Virtual method overriden by subclasses to process the module
   /// being operated on.
   virtual bool runOnModule(Module &M) = 0;
@@ -293,6 +302,9 @@ public:
   explicit FunctionPass(intptr_t pid) : Pass(PT_Function, pid) {}
   explicit FunctionPass(const void *pid) : Pass(PT_Function, pid) {}
 
+  /// createPrinterPass - Get a function printer pass.
+  Pass *createPrinterPass(raw_ostream &O, const std::string &Banner) const;
+
   /// doInitialization - Virtual method overridden by subclasses to do
   /// any necessary per-module initialization.
   ///
@@ -343,6 +355,9 @@ public:
   explicit BasicBlockPass(intptr_t pid) : Pass(PT_BasicBlock, pid) {}
   explicit BasicBlockPass(const void *pid) : Pass(PT_BasicBlock, pid) {}
 
+  /// createPrinterPass - Get a function printer pass.
+  Pass *createPrinterPass(raw_ostream &O, const std::string &Banner) const;
+
   /// doInitialization - Virtual method overridden by subclasses to do
   /// any necessary per-module initialization.
   ///