Add function to clear all virtual->physical mappings but not assigned

stack slots. This is in preparation for the iterative linear scan.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15032 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/VirtRegMap.h b/lib/CodeGen/VirtRegMap.h
index e9bfe76d4bf7785c8dc270997eb34cbc626a9a10..c76a222341e42dca15fc4a7e42f3def67e3abd11 100644 (file)
--- a/lib/CodeGen/VirtRegMap.h
+++ b/lib/CodeGen/VirtRegMap.h
@@ -87,6 +87,11 @@ namespace llvm {
             v2pMap_[virtReg] = NO_PHYS_REG;
         }
 
+        void clearAllVirt() {
+            v2pMap_.clear();
+            grow();
+        }
+
         bool hasStackSlot(unsigned virtReg) const {
             return getStackSlot(virtReg) != NO_STACK_SLOT;
         }