Refactor and check "onlyReadsMemory" before optimizing builtins.

This patch is mostly just refactoring a bunch of copy-and-pasted code, but
it also adds a check that the call instructions are readnone or readonly.
That check was already present for sin, cos, sqrt, log2, and exp2 calls, but
it was missing for the rest of the builtins being handled in this code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161282 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 30 insertions, 83 deletions

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index a6c2858794..ba5bd79722 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -5511,6 +5511,22 @@ bool SelectionDAGBuilder::visitMemCmpCall(const CallInst &I) {
   return false;
 }
 
+/// visitUnaryFloatCall - If a call instruction is a unary floating-point
+/// operation (as expected), translate it to an SDNode with the specified opcode
+/// and return true.
+bool SelectionDAGBuilder::visitUnaryFloatCall(const CallInst &I,
+                                              unsigned Opcode) {
+  // Sanity check that it really is a unary floating-point call.
+  if (I.getNumArgOperands() != 1 ||
+      !I.getArgOperand(0)->getType()->isFloatingPointTy() ||
+      I.getType() != I.getArgOperand(0)->getType() ||
+      !I.onlyReadsMemory())
+    return false;
+
+  SDValue Tmp = getValue(I.getArgOperand(0));
+  setValue(&I, DAG.getNode(Opcode, getCurDebugLoc(), Tmp.getValueType(), Tmp));
+  return true;
+}
 
 void SelectionDAGBuilder::visitCall(const CallInst &I) {
   // Handle inline assembly differently.
@@ -5553,7 +5569,8 @@ void SelectionDAGBuilder::visitCall(const CallInst &I) {
         if (I.getNumArgOperands() == 2 &&   // Basic sanity checks.
             I.getArgOperand(0)->getType()->isFloatingPointTy() &&
             I.getType() == I.getArgOperand(0)->getType() &&
-            I.getType() == I.getArgOperand(1)->getType()) {
+            I.getType() == I.getArgOperand(1)->getType() &&
+            I.onlyReadsMemory()) {
           SDValue LHS = getValue(I.getArgOperand(0));
           SDValue RHS = getValue(I.getArgOperand(1));
           setValue(&I, DAG.getNode(ISD::FCOPYSIGN, getCurDebugLoc(),
@@ -5564,139 +5581,68 @@ void SelectionDAGBuilder::visitCall(const CallInst &I) {
       case LibFunc::fabs:
       case LibFunc::fabsf:
       case LibFunc::fabsl:
-        if (I.getNumArgOperands() == 1 &&   // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FABS, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FABS))
           return;
-        }
         break;
       case LibFunc::sin:
       case LibFunc::sinf:
       case LibFunc::sinl:
-        if (I.getNumArgOperands() == 1 &&   // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType() &&
-            I.onlyReadsMemory()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FSIN, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FSIN))
           return;
-        }
         break;
       case LibFunc::cos:
       case LibFunc::cosf:
       case LibFunc::cosl:
-        if (I.getNumArgOperands() == 1 &&   // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType() &&
-            I.onlyReadsMemory()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FCOS, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FCOS))
           return;
-        }
         break;
       case LibFunc::sqrt:
       case LibFunc::sqrtf:
       case LibFunc::sqrtl:
-        if (I.getNumArgOperands() == 1 &&   // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType() &&
-            I.onlyReadsMemory()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FSQRT, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FSQRT))
           return;
-        }
         break;
       case LibFunc::floor:
       case LibFunc::floorf:
       case LibFunc::floorl:
-        if (I.getNumArgOperands() == 1 && // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FFLOOR, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FFLOOR))
           return;
-        }
         break;
       case LibFunc::nearbyint:
       case LibFunc::nearbyintf:
       case LibFunc::nearbyintl:
-        if (I.getNumArgOperands() == 1 && // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FNEARBYINT, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FNEARBYINT))
           return;
-        }
         break;
       case LibFunc::ceil:
       case LibFunc::ceilf:
       case LibFunc::ceill:
-        if (I.getNumArgOperands() == 1 && // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FCEIL, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FCEIL))
           return;
-        }
         break;
       case LibFunc::rint:
       case LibFunc::rintf:
       case LibFunc::rintl:
-        if (I.getNumArgOperands() == 1 && // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FRINT, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FRINT))
           return;
-        }
         break;
       case LibFunc::trunc:
       case LibFunc::truncf:
       case LibFunc::truncl:
-        if (I.getNumArgOperands() == 1 && // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FTRUNC, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FTRUNC))
           return;
-        }
         break;
       case LibFunc::log2:
       case LibFunc::log2f:
       case LibFunc::log2l:
-        if (I.getNumArgOperands() == 1 && // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType() &&
-            I.onlyReadsMemory()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FLOG2, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FLOG2))
           return;
-        }
         break;
       case LibFunc::exp2:
       case LibFunc::exp2f:
       case LibFunc::exp2l:
-        if (I.getNumArgOperands() == 1 && // Basic sanity checks.
-            I.getArgOperand(0)->getType()->isFloatingPointTy() &&
-            I.getType() == I.getArgOperand(0)->getType() &&
-            I.onlyReadsMemory()) {
-          SDValue Tmp = getValue(I.getArgOperand(0));
-          setValue(&I, DAG.getNode(ISD::FEXP2, getCurDebugLoc(),
-                                   Tmp.getValueType(), Tmp));
+        if (visitUnaryFloatCall(I, ISD::FEXP2))
           return;
-        }
         break;
       case LibFunc::memcmp:
         if (visitMemCmpCall(I))
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
index d0fde6f01d..4090002314 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
@@ -520,6 +520,7 @@ private:
   void visitPHI(const PHINode &I);
   void visitCall(const CallInst &I);
   bool visitMemCmpCall(const CallInst &I);
+  bool visitUnaryFloatCall(const CallInst &I, unsigned Opcode);
   void visitAtomicLoad(const LoadInst &I);
   void visitAtomicStore(const StoreInst &I);