Don't require BUNDLE headers in MachineInstr::getBundleSize().

It is possible to build MI bundles that don't begin with a BUNDLE
header. Add support for such bundles, counting all instructions inside
the bundle.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171985 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 10 insertions, 11 deletions

diff --git a/include/llvm/CodeGen/MachineInstr.h b/include/llvm/CodeGen/MachineInstr.h
index 89521e8fdb..3c7611f6a8 100644
--- a/include/llvm/CodeGen/MachineInstr.h
+++ b/include/llvm/CodeGen/MachineInstr.h
@@ -699,7 +699,11 @@ public:
     }
   }
 
-  /// getBundleSize - Return the number of instructions inside the MI bundle.
+  /// Return the number of instructions inside the MI bundle, excluding the
+  /// bundle header.
+  ///
+  /// This is the number of instructions that MachineBasicBlock::iterator
+  /// skips, 0 for unbundled instructions.
   unsigned getBundleSize() const;
 
   /// readsRegister - Return true if the MachineInstr reads the specified
diff --git a/lib/CodeGen/MachineInstr.cpp b/lib/CodeGen/MachineInstr.cpp
index a4d9813e50..53dbf03163 100644
--- a/lib/CodeGen/MachineInstr.cpp
+++ b/lib/CodeGen/MachineInstr.cpp
@@ -982,18 +982,13 @@ MachineInstr::getRegClassConstraint(unsigned OpIdx,
   return NULL;
 }
 
-/// getBundleSize - Return the number of instructions inside the MI bundle.
+/// Return the number of instructions inside the MI bundle, not counting the
+/// header instruction.
 unsigned MachineInstr::getBundleSize() const {
-  assert(isBundle() && "Expecting a bundle");
-
-  const MachineBasicBlock *MBB = getParent();
-  MachineBasicBlock::const_instr_iterator I = *this, E = MBB->instr_end();
+  MachineBasicBlock::const_instr_iterator I = this;
   unsigned Size = 0;
-  while ((++I != E) && I->isInsideBundle()) {
-    ++Size;
-  }
-  assert(Size > 1 && "Malformed bundle");
-
+  while (I->isBundledWithSucc())
+    ++Size, ++I;
   return Size;
 }