[PowerPC] Add asm/disasm support for dcbt with hint

Add assembler/disassembler support for dcbt/dcbtst (and aliases) with the hint
field specified (non-zero). Unforunately, the syntax for this instruction is
special in that it differs for server vs. embedded cores:
   dcbt ra, rb, th [server]
   dcbt th, ra, rb [embedded]
where th can be omitted when it is 0. dcbtst is the same. Thus we need to play
games in the parser and the printer to flip the operands around on the embedded
cores. We'll use the server syntax as the default (binutils currently uses the
embedded form by default, but IBM is changing that).

We also stop marking dcbtst as having unmodeled side effects (this is not
necessary, it is just a hint like dcbt -- noticed by inspection, so no separate
test case).

llvm-svn: 235657

1 files changed, 49 insertions, 0 deletions

diff --git a/llvm/lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp b/llvm/lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp
index 90ab7a558f8..9492e1d3f66 100644
--- a/llvm/lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp
+++ b/llvm/lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp
@@ -801,6 +801,40 @@ void PPCAsmParser::ProcessInstruction(MCInst &Inst,
                                       const OperandVector &Operands) {
   int Opcode = Inst.getOpcode();
   switch (Opcode) {
+  case PPC::DCBTx:
+  case PPC::DCBTT:
+  case PPC::DCBTSTx:
+  case PPC::DCBTSTT: {
+    MCInst TmpInst;
+    TmpInst.setOpcode((Opcode == PPC::DCBTx || Opcode == PPC::DCBTT) ?
+                      PPC::DCBT : PPC::DCBTST);
+    TmpInst.addOperand(MCOperand::CreateImm(
+      (Opcode == PPC::DCBTx || Opcode == PPC::DCBTSTx) ? 0 : 16));
+    TmpInst.addOperand(Inst.getOperand(0));
+    TmpInst.addOperand(Inst.getOperand(1));
+    Inst = TmpInst;
+    break;
+  }
+  case PPC::DCBTCT:
+  case PPC::DCBTDS: {
+    MCInst TmpInst;
+    TmpInst.setOpcode(PPC::DCBT);
+    TmpInst.addOperand(Inst.getOperand(2));
+    TmpInst.addOperand(Inst.getOperand(0));
+    TmpInst.addOperand(Inst.getOperand(1));
+    Inst = TmpInst;
+    break;
+  }
+  case PPC::DCBTSTCT:
+  case PPC::DCBTSTDS: {
+    MCInst TmpInst;
+    TmpInst.setOpcode(PPC::DCBTST);
+    TmpInst.addOperand(Inst.getOperand(2));
+    TmpInst.addOperand(Inst.getOperand(0));
+    TmpInst.addOperand(Inst.getOperand(1));
+    Inst = TmpInst;
+    break;
+  }
   case PPC::LAx: {
     MCInst TmpInst;
     TmpInst.setOpcode(PPC::LA);
@@ -1606,6 +1640,21 @@ bool PPCAsmParser::ParseInstruction(ParseInstructionInfo &Info, StringRef Name,
       return true;
   }
 
+  // We'll now deal with an unfortunate special case: the syntax for the dcbt
+  // and dcbtst instructions differs for server vs. embedded cores.
+  //  The syntax for dcbt is:
+  //    dcbt ra, rb, th [server]
+  //    dcbt th, ra, rb [embedded]
+  //  where th can be omitted when it is 0. dcbtst is the same. We take the
+  //  server form to be the default, so swap the operands if we're parsing for
+  //  an embedded core (they'll be swapped again upon printing).
+  if ((STI.getFeatureBits() & PPC::FeatureBookE) != 0 &&
+      Operands.size() == 4 &&
+      (Name == "dcbt" || Name == "dcbtst")) {
+    std::swap(Operands[1], Operands[3]);
+    std::swap(Operands[2], Operands[1]);
+  }
+
   return false;
 }