Add the PPC fcpsgn instruction

Modern PPC cores support a floating-point copysign instruction, and we can use
this to lower the FCOPYSIGN node (which is created from calls to the libm
copysign function). A couple of extra patterns are necessary because the
operand types of FCOPYSIGN need not agree.

llvm-svn: 188653

5 files changed, 45 insertions, 7 deletions

diff --git a/llvm/lib/Target/PowerPC/PPC.td b/llvm/lib/Target/PowerPC/PPC.td
index 806822c2961..0d950ee5a06 100644
--- a/llvm/lib/Target/PowerPC/PPC.td
+++ b/llvm/lib/Target/PowerPC/PPC.td
@@ -57,6 +57,8 @@ def FeatureMFOCRF    : SubtargetFeature<"mfocrf","HasMFOCRF", "true",
                                         "Enable the MFOCRF instruction">;
 def FeatureFSqrt     : SubtargetFeature<"fsqrt","HasFSQRT", "true",
                                         "Enable the fsqrt instruction">;
+def FeatureFCPSGN    : SubtargetFeature<"fcpsgn", "HasFCPSGN", "true",
+                                        "Enable the fcpsgn instruction">;
 def FeatureFRE       : SubtargetFeature<"fre", "HasFRE", "true",
                                         "Enable the fre instruction">;
 def FeatureFRES      : SubtargetFeature<"fres", "HasFRES", "true",
@@ -194,7 +196,7 @@ def : ProcessorModel<"e5500", PPCE5500Model,
                    FeatureSTFIWX, FeatureBookE, FeatureISEL]>;
 def : ProcessorModel<"a2", PPCA2Model,
                   [DirectiveA2, FeatureBookE, FeatureMFOCRF,
-                   FeatureFSqrt, FeatureFRE, FeatureFRES,
+                   FeatureFCPSGN, FeatureFSqrt, FeatureFRE, FeatureFRES,
                    FeatureFRSQRTE, FeatureFRSQRTES, FeatureRecipPrec,
                    FeatureSTFIWX, FeatureLFIWAX,
                    FeatureFPRND, FeatureFPCVT, FeatureISEL,
@@ -202,7 +204,7 @@ def : ProcessorModel<"a2", PPCA2Model,
                /*, Feature64BitRegs */]>;
 def : ProcessorModel<"a2q", PPCA2Model,
                   [DirectiveA2, FeatureBookE, FeatureMFOCRF,
-                   FeatureFSqrt, FeatureFRE, FeatureFRES,
+                   FeatureFCPSGN, FeatureFSqrt, FeatureFRE, FeatureFRES,
                    FeatureFRSQRTE, FeatureFRSQRTES, FeatureRecipPrec,
                    FeatureSTFIWX, FeatureLFIWAX,
                    FeatureFPRND, FeatureFPCVT, FeatureISEL,
@@ -228,19 +230,19 @@ def : ProcessorModel<"pwr5x", G5Model,
                    FeatureSTFIWX, FeatureFPRND, Feature64Bit]>;
 def : ProcessorModel<"pwr6", G5Model,
                   [DirectivePwr6, FeatureAltivec,
-                   FeatureMFOCRF, FeatureFSqrt, FeatureFRE,
+                   FeatureMFOCRF, FeatureFCPSGN, FeatureFSqrt, FeatureFRE,
                    FeatureFRES, FeatureFRSQRTE, FeatureFRSQRTES,
                    FeatureRecipPrec, FeatureSTFIWX, FeatureLFIWAX,
                    FeatureFPRND, Feature64Bit /*, Feature64BitRegs */]>;
 def : ProcessorModel<"pwr6x", G5Model,
                   [DirectivePwr5x, FeatureAltivec, FeatureMFOCRF,
-                   FeatureFSqrt, FeatureFRE, FeatureFRES,
+                   FeatureFCPSGN, FeatureFSqrt, FeatureFRE, FeatureFRES,
                    FeatureFRSQRTE, FeatureFRSQRTES, FeatureRecipPrec,
                    FeatureSTFIWX, FeatureLFIWAX,
                    FeatureFPRND, Feature64Bit]>;
 def : ProcessorModel<"pwr7", G5Model,
                   [DirectivePwr7, FeatureAltivec,
-                   FeatureMFOCRF, FeatureFSqrt, FeatureFRE,
+                   FeatureMFOCRF, FeatureFCPSGN, FeatureFSqrt, FeatureFRE,
                    FeatureFRES, FeatureFRSQRTE, FeatureFRSQRTES,
                    FeatureRecipPrec, FeatureSTFIWX, FeatureLFIWAX,
                    FeatureFPRND, FeatureFPCVT, FeatureISEL,
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 2b83a22ac67..bc55d383f1e 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -149,8 +149,13 @@ PPCTargetLowering::PPCTargetLowering(PPCTargetMachine &TM)
         Subtarget->hasFRSQRTES() && Subtarget->hasFRES()))
     setOperationAction(ISD::FSQRT, MVT::f32, Expand);
 
-  setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
-  setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
+  if (Subtarget->hasFCPSGN()) {
+    setOperationAction(ISD::FCOPYSIGN, MVT::f64, Legal);
+    setOperationAction(ISD::FCOPYSIGN, MVT::f32, Legal);
+  } else {
+    setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
+    setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
+  }
 
   if (Subtarget->hasFPRND()) {
     setOperationAction(ISD::FFLOOR, MVT::f64, Legal);
diff --git a/llvm/lib/Target/PowerPC/PPCInstrInfo.td b/llvm/lib/Target/PowerPC/PPCInstrInfo.td
index 84ddb3ffdb7..35e9935f7b7 100644
--- a/llvm/lib/Target/PowerPC/PPCInstrInfo.td
+++ b/llvm/lib/Target/PowerPC/PPCInstrInfo.td
@@ -785,6 +785,20 @@ multiclass XForm_26r<bits<6> opcode, bits<10> xo, dag OOL, dag IOL,
   }
 }
 
+multiclass XForm_28r<bits<6> opcode, bits<10> xo, dag OOL, dag IOL,
+                    string asmbase, string asmstr, InstrItinClass itin,
+                    list<dag> pattern> {
+  let BaseName = asmbase in {
+    def NAME : XForm_28<opcode, xo, OOL, IOL,
+                       !strconcat(asmbase, !strconcat(" ", asmstr)), itin,
+                       pattern>, RecFormRel;
+    let Defs = [CR1] in
+    def o    : XForm_28<opcode, xo, OOL, IOL,
+                       !strconcat(asmbase, !strconcat(". ", asmstr)), itin,
+                       []>, isDOT, RecFormRel;
+  }
+}
+
 multiclass AForm_1r<bits<6> opcode, bits<5> xo, dag OOL, dag IOL,
                     string asmbase, string asmstr, InstrItinClass itin,
                     list<dag> pattern> {
@@ -1762,6 +1776,14 @@ defm FNEGD  : XForm_26r<63, 40, (outs f8rc:$frD), (ins f8rc:$frB),
                         "fneg", "$frD, $frB", FPGeneral,
                         [(set f64:$frD, (fneg f64:$frB))]>;
 
+defm FCPSGNS : XForm_28r<63, 8, (outs f4rc:$frD), (ins f4rc:$frA, f4rc:$frB),
+                        "fcpsgn", "$frD, $frA, $frB", FPGeneral,
+                        [(set f32:$frD, (fcopysign f32:$frB, f32:$frA))]>;
+let Interpretation64Bit = 1 in
+defm FCPSGND : XForm_28r<63, 8, (outs f8rc:$frD), (ins f8rc:$frA, f8rc:$frB),
+                        "fcpsgn", "$frD, $frA, $frB", FPGeneral,
+                        [(set f64:$frD, (fcopysign f64:$frB, f64:$frA))]>;
+
 // Reciprocal estimates.
 defm FRE      : XForm_26r<63, 24, (outs f8rc:$frD), (ins f8rc:$frB),
                           "fre", "$frD, $frB", FPGeneral,
@@ -2270,6 +2292,12 @@ def : Pat<(fma (fneg f32:$A), f32:$C, f32:$B),
 def : Pat<(fma f32:$A, (fneg f32:$C), f32:$B),
           (FNMSUBS $A, $C, $B)>;
 
+// FCOPYSIGN's operand types need not agree.
+def : Pat<(fcopysign f64:$frB, f32:$frA),
+          (FCPSGND (COPY_TO_REGCLASS $frA, F8RC), $frB)>;
+def : Pat<(fcopysign f32:$frB, f64:$frA),
+          (FCPSGNS (COPY_TO_REGCLASS $frA, F4RC), $frB)>;
+
 include "PPCInstrAltivec.td"
 include "PPCInstr64Bit.td"
 
diff --git a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
index 12d0326855c..f975f5539c3 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
@@ -74,6 +74,7 @@ void PPCSubtarget::initializeEnvironment() {
   Use64BitRegs = false;
   HasAltivec = false;
   HasQPX = false;
+  HasFCPSGN = false;
   HasFSQRT = false;
   HasFRE = false;
   HasFRES = false;
diff --git a/llvm/lib/Target/PowerPC/PPCSubtarget.h b/llvm/lib/Target/PowerPC/PPCSubtarget.h
index 3f3fc0e9cda..a933bf69bbe 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.h
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.h
@@ -76,6 +76,7 @@ protected:
   bool IsPPC64;
   bool HasAltivec;
   bool HasQPX;
+  bool HasFCPSGN;
   bool HasFSQRT;
   bool HasFRE, HasFRES, HasFRSQRTE, HasFRSQRTES;
   bool HasRecipPrec;
@@ -171,6 +172,7 @@ public:
   bool isLittleEndian() const { return IsLittleEndian; }
 
   // Specific obvious features.
+  bool hasFCPSGN() const { return HasFCPSGN; }
   bool hasFSQRT() const { return HasFSQRT; }
   bool hasFRE() const { return HasFRE; }
   bool hasFRES() const { return HasFRES; }