[mips][mips64r6] bc1[tf] are not available on MIPS32r6/MIPS64r6

Summary:
Also tightened up the acceptable condition operand for these instructions
on MIPS-I to MIPS-III. Support for $fcc[1-7] was added in MIPS-IV. Prior
to that only $fcc0 is acceptable.

We currently don't optimize (BEQZ (NOT $a), $target) and similar. It's
probably best to do this in InstCombine.

Depends on D4111

Reviewers: jkolek, zoran.jovanovic, vmedic

Reviewed By: vmedic

Differential Revision: http://reviews.llvm.org/D4112

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210787 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 21 insertions, 8 deletions

diff --git a/lib/Target/Mips/AsmParser/MipsAsmParser.cpp b/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
index 3e0b9cef27..c9deae6afb 100644
--- a/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ b/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -174,6 +174,9 @@ class MipsAsmParser : public MCTargetAsmParser {
     return STI.getFeatureBits() & Mips::FeatureMicroMips;
   }
 
+  bool hasMips4() const { return STI.getFeatureBits() & Mips::FeatureMips4; }
+  bool hasMips32() const { return STI.getFeatureBits() & Mips::FeatureMips32; }
+
   bool parseRegister(unsigned &RegNum);
 
   bool eatComma(StringRef ErrorStr);
@@ -246,6 +249,9 @@ public:
   MCAsmParser &getParser() const { return Parser; }
   MCAsmLexer &getLexer() const { return Parser.getLexer(); }
 
+  /// True if all of $fcc0 - $fcc7 exist for the current ISA.
+  bool hasEightFccRegisters() const { return hasMips4() || hasMips32(); }
+
   /// Warn if RegNo is the current assembler temporary.
   void WarnIfAssemblerTemporary(int RegNo, SMLoc Loc);
 };
@@ -759,7 +765,11 @@ public:
     return isRegIdx() && RegIdx.Kind & RegKind_CCR && RegIdx.Index <= 31;
   }
   bool isFCCAsmReg() const {
-    return isRegIdx() && RegIdx.Kind & RegKind_FCC && RegIdx.Index <= 7;
+    if (!(isRegIdx() && RegIdx.Kind & RegKind_FCC))
+      return false;
+    if (!AsmParser.hasEightFccRegisters())
+      return RegIdx.Index == 0;
+    return RegIdx.Index <= 7;
   }
   bool isACCAsmReg() const {
     return isRegIdx() && RegIdx.Kind & RegKind_ACC && RegIdx.Index <= 3;
diff --git a/lib/Target/Mips/MicroMipsInstrFPU.td b/lib/Target/Mips/MicroMipsInstrFPU.td
index 9dbdc126ae..b93017a740 100644
--- a/lib/Target/Mips/MicroMipsInstrFPU.td
+++ b/lib/Target/Mips/MicroMipsInstrFPU.td
@@ -38,9 +38,9 @@ def FCMP_D32_MM : MMRel, CEQS_FT<"d", AFGR64, II_C_CC_D, MipsFPCmp>,
                   CEQS_FM_MM<1>;
 
 def BC1F_MM : MMRel, BC1F_FT<"bc1f", brtarget_mm, IIBranch, MIPS_BRANCH_F>,
-              BC1F_FM_MM<0x1c>;
+              BC1F_FM_MM<0x1c>, ISA_MIPS1_NOT_32R6_64R6;
 def BC1T_MM : MMRel, BC1F_FT<"bc1t", brtarget_mm, IIBranch, MIPS_BRANCH_T>,
-              BC1F_FM_MM<0x1d>;
+              BC1F_FM_MM<0x1d>, ISA_MIPS1_NOT_32R6_64R6;
 
 def CEIL_W_S_MM  : MMRel, ABSS_FT<"ceil.w.s", FGR32Opnd, FGR32Opnd, II_CEIL>,
                    ROUND_W_FM_MM<0, 0x6c>;
diff --git a/lib/Target/Mips/Mips32r6InstrInfo.td b/lib/Target/Mips/Mips32r6InstrInfo.td
index d730d418ea..ea164208be 100644
--- a/lib/Target/Mips/Mips32r6InstrInfo.td
+++ b/lib/Target/Mips/Mips32r6InstrInfo.td
@@ -28,7 +28,6 @@ include "Mips32r6InstrFormats.td"
 // Removed: bc1any2, bc1any4
 // Removed: bgezal
 // Removed: bltzal
-// Removed: bc1[ft]
 // Rencoded: [ls][wd]c2
 
 def brtarget21 : Operand<OtherVT> {
diff --git a/lib/Target/Mips/MipsInstrFPU.td b/lib/Target/Mips/MipsInstrFPU.td
index 73406ae667..cf8d2b2ff9 100644
--- a/lib/Target/Mips/MipsInstrFPU.td
+++ b/lib/Target/Mips/MipsInstrFPU.td
@@ -517,9 +517,9 @@ def MIPS_BRANCH_F  : PatLeaf<(i32 0)>;
 def MIPS_BRANCH_T  : PatLeaf<(i32 1)>;
 
 def BC1F : MMRel, BC1F_FT<"bc1f", brtarget, IIBranch, MIPS_BRANCH_F>,
-           BC1F_FM<0, 0>;
+           BC1F_FM<0, 0>, ISA_MIPS1_NOT_32R6_64R6;
 def BC1T : MMRel, BC1F_FT<"bc1t", brtarget, IIBranch, MIPS_BRANCH_T>,
-           BC1F_FM<0, 1>;
+           BC1F_FM<0, 1>, ISA_MIPS1_NOT_32R6_64R6;
 
 //===----------------------------------------------------------------------===//
 // Floating Point Flag Conditions
@@ -583,8 +583,10 @@ def ExtractElementF64_64 : ExtractElementF64Base<FGR64Opnd>,
 //===----------------------------------------------------------------------===//
 // InstAliases.
 //===----------------------------------------------------------------------===//
-def : MipsInstAlias<"bc1t $offset", (BC1T FCC0, brtarget:$offset)>;
-def : MipsInstAlias<"bc1f $offset", (BC1F FCC0, brtarget:$offset)>;
+def : MipsInstAlias<"bc1t $offset", (BC1T FCC0, brtarget:$offset)>,
+      ISA_MIPS1_NOT_32R6_64R6;
+def : MipsInstAlias<"bc1f $offset", (BC1F FCC0, brtarget:$offset)>,
+      ISA_MIPS1_NOT_32R6_64R6;
 
 //===----------------------------------------------------------------------===//
 // Floating Point Patterns
diff --git a/lib/Target/Mips/MipsSEISelLowering.cpp b/lib/Target/Mips/MipsSEISelLowering.cpp
index 2b196f873f..cc7ed714be 100644
--- a/lib/Target/Mips/MipsSEISelLowering.cpp
+++ b/lib/Target/Mips/MipsSEISelLowering.cpp
@@ -185,6 +185,8 @@ MipsSETargetLowering::MipsSETargetLowering(MipsTargetMachine &TM)
     setOperationAction(ISD::SELECT, MVT::f64, Legal);
     setOperationAction(ISD::SELECT_CC, MVT::f64, Expand);
 
+    setOperationAction(ISD::BRCOND, MVT::Other, Legal);
+
     // Floating point > and >= are supported via < and <=
     setCondCodeAction(ISD::SETOGE, MVT::f32, Expand);
     setCondCodeAction(ISD::SETOGT, MVT::f32, Expand);