[llvm-commits] [llvm] r57513 - in /llvm/trunk: lib/Transforms/Scalar/InstructionCombining.cpp test/Transforms/InstCombine/and-fcmp.ll

Evan Cheng evan.cheng at apple.com
Tue Oct 14 11:13:38 PDT 2008


Author: evancheng
Date: Tue Oct 14 13:13:38 2008
New Revision: 57513

URL: http://llvm.org/viewvc/llvm-project?rev=57513&view=rev
Log:
- Somehow I forgot about one / une.
- Renumber fcmp predicates to match their icmp counterparts.
- Try swapping operands to expose more optimization opportunities.

Modified:
    llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
    llvm/trunk/test/Transforms/InstCombine/and-fcmp.ll

Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=57513&r1=57512&r2=57513&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Tue Oct 14 13:13:38 2008
@@ -3124,14 +3124,16 @@
   switch (CC) {
   case FCmpInst::FCMP_ORD: isOrdered = true; return 0;  // 000
   case FCmpInst::FCMP_UNO:                   return 0;  // 000
-  case FCmpInst::FCMP_OEQ: isOrdered = true; return 1;  // 001
-  case FCmpInst::FCMP_UEQ:                   return 1;  // 001
-  case FCmpInst::FCMP_OGT: isOrdered = true; return 2;  // 010
-  case FCmpInst::FCMP_UGT:                   return 2;  // 010
+  case FCmpInst::FCMP_OGT: isOrdered = true; return 1;  // 001
+  case FCmpInst::FCMP_UGT:                   return 1;  // 001
+  case FCmpInst::FCMP_OEQ: isOrdered = true; return 2;  // 010
+  case FCmpInst::FCMP_UEQ:                   return 2;  // 010
   case FCmpInst::FCMP_OGE: isOrdered = true; return 3;  // 011
   case FCmpInst::FCMP_UGE:                   return 3;  // 011
   case FCmpInst::FCMP_OLT: isOrdered = true; return 4;  // 100
   case FCmpInst::FCMP_ULT:                   return 4;  // 100
+  case FCmpInst::FCMP_ONE: isOrdered = true; return 5;  // 101
+  case FCmpInst::FCMP_UNE:                   return 5;  // 101
   case FCmpInst::FCMP_OLE: isOrdered = true; return 6;  // 110
   case FCmpInst::FCMP_ULE:                   return 6;  // 110
   default:
@@ -3181,7 +3183,7 @@
 static Value *getFCmpValue(bool isordered, unsigned code,
                            Value *LHS, Value *RHS) {
   switch (code) {
-  default: assert(0 && "Illegal ICmp code!");
+  default: assert(0 && "Illegal FCmp code!");
   case  0:
     if (isordered)
       return new FCmpInst(FCmpInst::FCMP_ORD, LHS, RHS);
@@ -3189,14 +3191,14 @@
       return new FCmpInst(FCmpInst::FCMP_UNO, LHS, RHS);
   case  1: 
     if (isordered)
-      return new FCmpInst(FCmpInst::FCMP_OEQ, LHS, RHS);
+      return new FCmpInst(FCmpInst::FCMP_OGT, LHS, RHS);
     else
-      return new FCmpInst(FCmpInst::FCMP_UEQ, LHS, RHS);
+      return new FCmpInst(FCmpInst::FCMP_UGT, LHS, RHS);
   case  2: 
     if (isordered)
-      return new FCmpInst(FCmpInst::FCMP_OGT, LHS, RHS);
+      return new FCmpInst(FCmpInst::FCMP_OEQ, LHS, RHS);
     else
-      return new FCmpInst(FCmpInst::FCMP_UGT, LHS, RHS);
+      return new FCmpInst(FCmpInst::FCMP_UEQ, LHS, RHS);
   case  3: 
     if (isordered)
       return new FCmpInst(FCmpInst::FCMP_OGE, LHS, RHS);
@@ -3209,6 +3211,11 @@
       return new FCmpInst(FCmpInst::FCMP_ULT, LHS, RHS);
   case  5: 
     if (isordered)
+      return new FCmpInst(FCmpInst::FCMP_ONE, LHS, RHS);
+    else
+      return new FCmpInst(FCmpInst::FCMP_UNE, LHS, RHS);
+  case  6: 
+    if (isordered)
       return new FCmpInst(FCmpInst::FCMP_OLE, LHS, RHS);
     else
       return new FCmpInst(FCmpInst::FCMP_ULE, LHS, RHS);
@@ -3973,6 +3980,11 @@
         FCmpInst::Predicate Op0CC, Op1CC;
         if (match(Op0, m_FCmp(Op0CC, m_Value(Op0LHS), m_Value(Op0RHS))) &&
             match(Op1, m_FCmp(Op1CC, m_Value(Op1LHS), m_Value(Op1RHS)))) {
+          if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) {
+            // Swap RHS operands to match LHS.
+            Op1CC = FCmpInst::getSwappedPredicate(Op1CC);
+            std::swap(Op1LHS, Op1RHS);
+          }
           if (Op0LHS == Op1LHS && Op0RHS == Op1RHS) {
             // Simplify (fcmp cc0 x, y) & (fcmp cc1 x, y).
             if (Op0CC == Op1CC)

Modified: llvm/trunk/test/Transforms/InstCombine/and-fcmp.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/and-fcmp.ll?rev=57513&r1=57512&r2=57513&view=diff

==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/and-fcmp.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/and-fcmp.ll Tue Oct 14 13:13:38 2008
@@ -1,4 +1,4 @@
-; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep fcmp | count 2
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep fcmp | count 3
 ; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep ret | grep 0
 
 define zeroext i8 @t1(float %x, float %y) nounwind {
@@ -24,3 +24,11 @@
        %retval = zext i1 %c to i8
        ret i8 %retval
 }
+
+define zeroext i8 @t4(float %x, float %y) nounwind {
+       %a = fcmp one float %y, %x
+       %b = fcmp ord float %x, %y
+       %c = and i1 %a, %b
+       %retval = zext i1 %c to i8
+       ret i8 %retval
+}





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