[llvm-commits] [llvm] r158310 - /llvm/trunk/include/llvm/CodeGen/MachineBasicBlock.h

[Jakob Stoklund Olesen]

Author: stoklund
Date: Mon Jun 11 10:11:12 2012
New Revision: 158310

URL: http://llvm.org/viewvc/llvm-project?rev=158310&view=rev
Log:
Fix a problem with the reverse bundle iterators.

This showed up the first time rend() was called on a bundled instruction
in the Mips backend.

Also avoid dereferencing end() in bundle_iterator::operator++().

We still don't have a place to put unit tests for this stuff.

Modified:
    llvm/trunk/include/llvm/CodeGen/MachineBasicBlock.h

Modified: llvm/trunk/include/llvm/CodeGen/MachineBasicBlock.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/MachineBasicBlock.h?rev=158310&r1=158309&r2=158310&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/MachineBasicBlock.h (original)
+++ llvm/trunk/include/llvm/CodeGen/MachineBasicBlock.h Mon Jun 11 10:11:12 2012
@@ -143,10 +143,7 @@
     IterTy MII;
 
   public:
-    bundle_iterator(IterTy mii) : MII(mii) {
-      assert(!MII->isInsideBundle() &&
-             "It's not legal to initialize bundle_iterator with a bundled MI");
-    }
+    bundle_iterator(IterTy mii) : MII(mii) {}
 
     bundle_iterator(Ty &mi) : MII(mi) {
       assert(!mi.isInsideBundle() &&
@@ -176,29 +173,24 @@
 
     // Increment and decrement operators...
     bundle_iterator &operator--() {      // predecrement - Back up
-      do {
-        --MII;
-      } while (MII->isInsideBundle());
+      do --MII;
+      while (MII->isInsideBundle());
       return *this;
     }
     bundle_iterator &operator++() {      // preincrement - Advance
-      do {
-        ++MII;
-      } while (MII->isInsideBundle());
+      IterTy E = MII->getParent()->instr_end();
+      do ++MII;
+      while (MII != E && MII->isInsideBundle());
       return *this;
     }
     bundle_iterator operator--(int) {    // postdecrement operators...
       bundle_iterator tmp = *this;
-      do {
-        --MII;
-      } while (MII->isInsideBundle());
+      --*this;
       return tmp;
     }
     bundle_iterator operator++(int) {    // postincrement operators...
       bundle_iterator tmp = *this;
-      do {
-        ++MII;
-      } while (MII->isInsideBundle());
+      ++*this;
       return tmp;
     }
 
@@ -238,42 +230,14 @@
   reverse_instr_iterator       instr_rend  ()       { return Insts.rend();   }
   const_reverse_instr_iterator instr_rend  () const { return Insts.rend();   }
 
-  iterator                begin()       { return Insts.begin();  }
-  const_iterator          begin() const { return Insts.begin();  }
-  iterator                  end()       {
-    instr_iterator II = instr_end();
-    if (II != instr_begin()) {
-      while (II->isInsideBundle())
-        --II;
-    }
-    return II;
-  }
-  const_iterator            end() const {
-    const_instr_iterator II = instr_end();
-    if (II != instr_begin()) {
-      while (II->isInsideBundle())
-        --II;
-    }
-    return II;
-  }
-  reverse_iterator       rbegin()       {
-    reverse_instr_iterator II = instr_rbegin();
-    if (II != instr_rend()) {
-      while (II->isInsideBundle())
-        ++II;
-    }
-    return II;
-  }
-  const_reverse_iterator rbegin() const {
-    const_reverse_instr_iterator II = instr_rbegin();
-    if (II != instr_rend()) {
-      while (II->isInsideBundle())
-        ++II;
-    }
-    return II;
-  }
-  reverse_iterator       rend  ()       { return Insts.rend();   }
-  const_reverse_iterator rend  () const { return Insts.rend();   }
+  iterator                begin()       { return instr_begin();  }
+  const_iterator          begin() const { return instr_begin();  }
+  iterator                end  ()       { return instr_end();    }
+  const_iterator          end  () const { return instr_end();    }
+  reverse_iterator       rbegin()       { return instr_rbegin(); }
+  const_reverse_iterator rbegin() const { return instr_rbegin(); }
+  reverse_iterator       rend  ()       { return instr_rend();   }
+  const_reverse_iterator rend  () const { return instr_rend();   }
 
 
   // Machine-CFG iterators