[llvm-commits] [llvm] r82778 - /llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp

[Dale Johannesen]

Author: johannes
Date: Fri Sep 25 12:23:22 2009
New Revision: 82778

URL: http://llvm.org/viewvc/llvm-project?rev=82778&view=rev
Log:
Generate FSQRT from calls to the sqrt function, which
allows appropriate backends to generate a sqrt instruction.

On x86, this isn't done at -O0 because we go through
FastISel instead.  This is a behavior change from before
this series of sqrt patches started.  I think this is OK
considering that compile speed is most important at -O0, but
could be convinced otherwise.


Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp?rev=82778&r1=82777&r2=82778&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp Fri Sep 25 12:23:22 2009
@@ -4576,6 +4576,15 @@
                                    Tmp.getValueType(), Tmp));
           return;
         }
+      } else if (Name == "sqrt" || Name == "sqrtf" || Name == "sqrtl") {
+        if (I.getNumOperands() == 2 &&   // Basic sanity checks.
+            I.getOperand(1)->getType()->isFloatingPoint() &&
+            I.getType() == I.getOperand(1)->getType()) {
+          SDValue Tmp = getValue(I.getOperand(1));
+          setValue(&I, DAG.getNode(ISD::FSQRT, getCurDebugLoc(),
+                                   Tmp.getValueType(), Tmp));
+          return;
+        }
       }
     }
   } else if (isa<InlineAsm>(I.getOperand(0))) {