LV code on machine instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/LiveVar/LiveVarSet.cpp b/lib/Analysis/LiveVar/LiveVarSet.cpp
index c893817..07dc128 100644
--- a/lib/Analysis/LiveVar/LiveVarSet.cpp
+++ b/lib/Analysis/LiveVar/LiveVarSet.cpp
@@ -1,9 +1,42 @@
#include "llvm/Analysis/LiveVar/LiveVarSet.h"
+#include "llvm/CodeGen/MachineInstr.h"
-// This function applies an instruction to a live var set (accepts OutSet) and
-// makes necessary changes to it (produces InSet)
+// This function applies a machine instr to a live var set (accepts OutSet) and
+// makes necessary changes to it (produces InSet). Note that two for loops are
+// used to first kill all defs and then to add all uses. This is because there
+// can be instructions like Val = Val + 1 since we allow multipe defs to a
+// machine instruction operand.
+
+void LiveVarSet::applyTranferFuncForMInst(const MachineInstr *const MInst)
+{
+
+ for( MachineInstr::val_op_const_iterator OpI(MInst); !OpI.done() ; OpI++) {
+
+ if( OpI.isDef() ) { // kill only if this operand is a def
+ remove(*OpI); // this definition kills any uses
+ }
+
+ }
+
+ for( MachineInstr::val_op_const_iterator OpI(MInst); !OpI.done() ; OpI++) {
+
+ if ( ((*OpI)->getType())->isLabelType()) continue; // don't process labels
+
+ if( ! OpI.isDef() ) { // add only if this operand is a use
+ add( *OpI ); // An operand is a use - so add to use set
+ }
+ }
+}
+
+
+
+
+
+
+
+#if 0
void LiveVarSet::applyTranferFuncForInst(const Instruction *const Inst)
{
@@ -18,3 +51,4 @@
}
}
+#endif