Optimized usage of new SwitchInst case values (IntegersSubset type) in Local.cpp, Execution.cpp and BitcodeWriter.cpp.

I got about 1% of compile-time improvement on my machines (Ubuntu 11.10 i386 and Ubuntu 12.04 x64).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159076 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 29 insertions, 9 deletions

diff --git a/lib/ExecutionEngine/Interpreter/Execution.cpp b/lib/ExecutionEngine/Interpreter/Execution.cpp
index 89c35438ef..5202b09165 100644
--- a/lib/ExecutionEngine/Interpreter/Execution.cpp
+++ b/lib/ExecutionEngine/Interpreter/Execution.cpp
@@ -651,20 +651,40 @@ void Interpreter::visitSwitchInst(SwitchInst &I) {
   // Check to see if any of the cases match...
   BasicBlock *Dest = 0;
   for (SwitchInst::CaseIt i = I.case_begin(), e = I.case_end(); i != e; ++i) {
-    IntegersSubset Case = i.getCaseValueEx();
-    for (unsigned n = 0, en = Case.getNumItems(); n != en; ++n) {
-      IntegersSubset::Range r = Case.getItem(n);
+    IntegersSubset& Case = i.getCaseValueEx();
+    if (Case.isSingleNumber()) {
       // FIXME: Currently work with ConstantInt based numbers.
-      const ConstantInt *LowCI = r.getLow().toConstantInt();
-      const ConstantInt *HighCI = r.getHigh().toConstantInt();
-      GenericValue Low = getOperandValue(const_cast<ConstantInt*>(LowCI), SF);
-      GenericValue High = getOperandValue(const_cast<ConstantInt*>(HighCI), SF);
-      if (executeICMP_ULE(Low, CondVal, ElTy).IntVal != 0 &&
-          executeICMP_ULE(CondVal, High, ElTy).IntVal != 0) {
+      const ConstantInt *CI = Case.getSingleNumber(0).toConstantInt();
+      GenericValue Val = getOperandValue(const_cast<ConstantInt*>(CI), SF);
+      if (executeICMP_EQ(Val, CondVal, ElTy).IntVal != 0) {
         Dest = cast<BasicBlock>(i.getCaseSuccessor());
         break;        
       }
     }
+    if (Case.isSingleNumbersOnly()) {
+      for (unsigned n = 0, en = Case.getNumItems(); n != en; ++n) {
+        // FIXME: Currently work with ConstantInt based numbers.
+        const ConstantInt *CI = Case.getSingleNumber(n).toConstantInt();
+        GenericValue Val = getOperandValue(const_cast<ConstantInt*>(CI), SF);
+        if (executeICMP_EQ(Val, CondVal, ElTy).IntVal != 0) {
+          Dest = cast<BasicBlock>(i.getCaseSuccessor());
+          break;        
+        }
+      }      
+    } else
+      for (unsigned n = 0, en = Case.getNumItems(); n != en; ++n) {
+        IntegersSubset::Range r = Case.getItem(n);
+        // FIXME: Currently work with ConstantInt based numbers.
+        const ConstantInt *LowCI = r.getLow().toConstantInt();
+        const ConstantInt *HighCI = r.getHigh().toConstantInt();
+        GenericValue Low = getOperandValue(const_cast<ConstantInt*>(LowCI), SF);
+        GenericValue High = getOperandValue(const_cast<ConstantInt*>(HighCI), SF);
+        if (executeICMP_ULE(Low, CondVal, ElTy).IntVal != 0 &&
+            executeICMP_ULE(CondVal, High, ElTy).IntVal != 0) {
+          Dest = cast<BasicBlock>(i.getCaseSuccessor());
+          break;        
+        }
+      }
   }
   if (!Dest) Dest = I.getDefaultDest();   // No cases matched: use default
   SwitchToNewBasicBlock(Dest, SF);