Do away with addLegalFPImmediate. Add a target hook isFPImmLegal which returns true if the fp immediate can be natively codegened by target.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85281 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 13 insertions, 5 deletions

diff --git a/lib/Target/Alpha/AlphaISelLowering.cpp b/lib/Target/Alpha/AlphaISelLowering.cpp
index b3f865cf4a..b2b738db2e 100644
--- a/lib/Target/Alpha/AlphaISelLowering.cpp
+++ b/lib/Target/Alpha/AlphaISelLowering.cpp
@@ -157,11 +157,6 @@ AlphaTargetLowering::AlphaTargetLowering(TargetMachine &TM)
 
   setStackPointerRegisterToSaveRestore(Alpha::R30);
 
-  addLegalFPImmediate(APFloat(+0.0)); //F31
-  addLegalFPImmediate(APFloat(+0.0f)); //F31
-  addLegalFPImmediate(APFloat(-0.0)); //-F31
-  addLegalFPImmediate(APFloat(-0.0f)); //-F31
-
   setJumpBufSize(272);
   setJumpBufAlignment(16);
 
@@ -919,3 +914,11 @@ AlphaTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
   // The Alpha target isn't yet aware of offsets.
   return false;
 }
+
+bool AlphaTargetLowering::isFPImmLegal(const APFloat &Imm) const {
+  // +0.0   F31
+  // +0.0f  F31
+  // -0.0  -F31
+  // -0.0f -F31
+  return Imm.isZero() || Imm.isNegZero();
+}
diff --git a/lib/Target/Alpha/AlphaISelLowering.h b/lib/Target/Alpha/AlphaISelLowering.h
index b580c9d712..fbffbed939 100644
--- a/lib/Target/Alpha/AlphaISelLowering.h
+++ b/lib/Target/Alpha/AlphaISelLowering.h
@@ -102,6 +102,11 @@ namespace llvm {
     /// getFunctionAlignment - Return the Log2 alignment of this function.
     virtual unsigned getFunctionAlignment(const Function *F) const;
 
+    /// isFPImmLegal - Returns true if the target can instruction select the
+    /// specified FP immediate natively. If false, the legalizer will
+    /// materialize the FP immediate as a load from a constant pool.
+    virtual bool isFPImmLegal(const APFloat &Imm) const;
+
   private:
     // Helpers for custom lowering.
     void LowerVAARG(SDNode *N, SDValue &Chain, SDValue &DataPtr,