Inlining and unrolling heuristics should be aware of free truncs.

We want heuristics to be based on accurate data, but more importantly
we don't want llvm to behave randomly. A benign trunc inserted by an
upstream pass should not cause a wild swings in optimization
level. See PR11034. It's a general problem with threshold-based
heuristics, but we can make it less bad.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140919 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 2 deletions

diff --git a/include/llvm/Analysis/CodeMetrics.h b/include/llvm/Analysis/CodeMetrics.h
index 9433d07a2b..d96dd82b35 100644
--- a/include/llvm/Analysis/CodeMetrics.h
+++ b/include/llvm/Analysis/CodeMetrics.h
@@ -18,6 +18,9 @@
 #include "llvm/ADT/DenseMap.h"
 
 namespace llvm {
+
+  class TargetData;
+
   // CodeMetrics - Calculate size and a few similar metrics for a set of
   // basic blocks.
   struct CodeMetrics {
@@ -68,11 +71,11 @@ namespace llvm {
 
     /// analyzeBasicBlock - Add information about the specified basic block
     /// to the current structure.
-    void analyzeBasicBlock(const BasicBlock *BB);
+    void analyzeBasicBlock(const BasicBlock *BB, const TargetData *TD = 0);
 
     /// analyzeFunction - Add information about the specified function
     /// to the current structure.
-    void analyzeFunction(Function *F);
+    void analyzeFunction(Function *F, const TargetData *TD = 0);
 
     /// CountCodeReductionForConstant - Figure out an approximation for how
     /// many instructions will be constant folded if the specified value is