[llvm] r259326 - add helper function for minnum/maxnum ; NFC

[Sanjay Patel via llvm-commits]

Author: spatel
Date: Sun Jan 31 10:35:23 2016
New Revision: 259326

URL: http://llvm.org/viewvc/llvm-project?rev=259326&view=rev
Log:
add helper function for minnum/maxnum ; NFC

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp?rev=259326&r1=259325&r2=259326&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp Sun Jan 31 10:35:23 2016
@@ -677,6 +677,82 @@ static Value *simplifyX86vpcom(const Int
   return nullptr;
 }
 
+static Value *simplifyMinnumMaxnum(const IntrinsicInst &II) {
+  Value *Arg0 = II.getArgOperand(0);
+  Value *Arg1 = II.getArgOperand(1);
+
+  // fmin(x, x) -> x
+  if (Arg0 == Arg1)
+    return Arg0;
+
+  const auto *C1 = dyn_cast<ConstantFP>(Arg1);
+
+  // fmin(x, nan) -> x
+  if (C1 && C1->isNaN())
+    return Arg0;
+
+  // This is the value because if undef were NaN, we would return the other
+  // value and cannot return a NaN unless both operands are.
+  //
+  // fmin(undef, x) -> x
+  if (isa<UndefValue>(Arg0))
+    return Arg1;
+
+  // fmin(x, undef) -> x
+  if (isa<UndefValue>(Arg1))
+    return Arg0;
+
+  Value *X = nullptr;
+  Value *Y = nullptr;
+  if (II.getIntrinsicID() == Intrinsic::minnum) {
+    // fmin(x, fmin(x, y)) -> fmin(x, y)
+    // fmin(y, fmin(x, y)) -> fmin(x, y)
+    if (match(Arg1, m_FMin(m_Value(X), m_Value(Y)))) {
+      if (Arg0 == X || Arg0 == Y)
+        return Arg1;
+    }
+
+    // fmin(fmin(x, y), x) -> fmin(x, y)
+    // fmin(fmin(x, y), y) -> fmin(x, y)
+    if (match(Arg0, m_FMin(m_Value(X), m_Value(Y)))) {
+      if (Arg1 == X || Arg1 == Y)
+        return Arg0;
+    }
+
+    // TODO: fmin(nnan x, inf) -> x
+    // TODO: fmin(nnan ninf x, flt_max) -> x
+    if (C1 && C1->isInfinity()) {
+      // fmin(x, -inf) -> -inf
+      if (C1->isNegative())
+        return Arg1;
+    }
+  } else {
+    assert(II.getIntrinsicID() == Intrinsic::maxnum);
+    // fmax(x, fmax(x, y)) -> fmax(x, y)
+    // fmax(y, fmax(x, y)) -> fmax(x, y)
+    if (match(Arg1, m_FMax(m_Value(X), m_Value(Y)))) {
+      if (Arg0 == X || Arg0 == Y)
+        return Arg1;
+    }
+
+    // fmax(fmax(x, y), x) -> fmax(x, y)
+    // fmax(fmax(x, y), y) -> fmax(x, y)
+    if (match(Arg0, m_FMax(m_Value(X), m_Value(Y)))) {
+      if (Arg1 == X || Arg1 == Y)
+        return Arg0;
+    }
+
+    // TODO: fmax(nnan x, -inf) -> x
+    // TODO: fmax(nnan ninf x, -flt_max) -> x
+    if (C1 && C1->isInfinity()) {
+      // fmax(x, inf) -> inf
+      if (!C1->isNegative())
+        return Arg1;
+    }
+  }
+  return nullptr;
+}
+
 /// CallInst simplification. This mostly only handles folding of intrinsic
 /// instructions. For normal calls, it allows visitCallSite to do the heavy
 /// lifting.
@@ -885,84 +961,14 @@ Instruction *InstCombiner::visitCallInst
   case Intrinsic::maxnum: {
     Value *Arg0 = II->getArgOperand(0);
     Value *Arg1 = II->getArgOperand(1);
-
-    // fmin(x, x) -> x
-    if (Arg0 == Arg1)
-      return ReplaceInstUsesWith(CI, Arg0);
-
-    const ConstantFP *C0 = dyn_cast<ConstantFP>(Arg0);
-    const ConstantFP *C1 = dyn_cast<ConstantFP>(Arg1);
-
-    // Canonicalize constants into the RHS.
-    if (C0 && !C1) {
+    // Canonicalize constants to the RHS.
+    if (isa<ConstantFP>(Arg0) && !isa<ConstantFP>(Arg1)) {
       II->setArgOperand(0, Arg1);
       II->setArgOperand(1, Arg0);
       return II;
     }
-
-    // fmin(x, nan) -> x
-    if (C1 && C1->isNaN())
-      return ReplaceInstUsesWith(CI, Arg0);
-
-    // This is the value because if undef were NaN, we would return the other
-    // value and cannot return a NaN unless both operands are.
-    //
-    // fmin(undef, x) -> x
-    if (isa<UndefValue>(Arg0))
-      return ReplaceInstUsesWith(CI, Arg1);
-
-    // fmin(x, undef) -> x
-    if (isa<UndefValue>(Arg1))
-      return ReplaceInstUsesWith(CI, Arg0);
-
-    Value *X = nullptr;
-    Value *Y = nullptr;
-    if (II->getIntrinsicID() == Intrinsic::minnum) {
-      // fmin(x, fmin(x, y)) -> fmin(x, y)
-      // fmin(y, fmin(x, y)) -> fmin(x, y)
-      if (match(Arg1, m_FMin(m_Value(X), m_Value(Y)))) {
-        if (Arg0 == X || Arg0 == Y)
-          return ReplaceInstUsesWith(CI, Arg1);
-      }
-
-      // fmin(fmin(x, y), x) -> fmin(x, y)
-      // fmin(fmin(x, y), y) -> fmin(x, y)
-      if (match(Arg0, m_FMin(m_Value(X), m_Value(Y)))) {
-        if (Arg1 == X || Arg1 == Y)
-          return ReplaceInstUsesWith(CI, Arg0);
-      }
-
-      // TODO: fmin(nnan x, inf) -> x
-      // TODO: fmin(nnan ninf x, flt_max) -> x
-      if (C1 && C1->isInfinity()) {
-        // fmin(x, -inf) -> -inf
-        if (C1->isNegative())
-          return ReplaceInstUsesWith(CI, Arg1);
-      }
-    } else {
-      assert(II->getIntrinsicID() == Intrinsic::maxnum);
-      // fmax(x, fmax(x, y)) -> fmax(x, y)
-      // fmax(y, fmax(x, y)) -> fmax(x, y)
-      if (match(Arg1, m_FMax(m_Value(X), m_Value(Y)))) {
-        if (Arg0 == X || Arg0 == Y)
-          return ReplaceInstUsesWith(CI, Arg1);
-      }
-
-      // fmax(fmax(x, y), x) -> fmax(x, y)
-      // fmax(fmax(x, y), y) -> fmax(x, y)
-      if (match(Arg0, m_FMax(m_Value(X), m_Value(Y)))) {
-        if (Arg1 == X || Arg1 == Y)
-          return ReplaceInstUsesWith(CI, Arg0);
-      }
-
-      // TODO: fmax(nnan x, -inf) -> x
-      // TODO: fmax(nnan ninf x, -flt_max) -> x
-      if (C1 && C1->isInfinity()) {
-        // fmax(x, inf) -> inf
-        if (!C1->isNegative())
-          return ReplaceInstUsesWith(CI, Arg1);
-      }
-    }
+    if (Value *V = simplifyMinnumMaxnum(*II))
+      return ReplaceInstUsesWith(*II, V);
     break;
   }
   case Intrinsic::ppc_altivec_lvx: