This change adds co-processor condition branching and conditional traps to the Sparc back-end.

This will allow inline assembler code to utilize these features, but no automatic lowering is provided, except for the previously provided @llvm.trap, which lowers to "ta 5".

The change also separates out the different assembly language syntaxes for V8 and V9 Sparc. Previously, only V9 Sparc assembly syntax was provided.

The change also corrects the selection order of trap disassembly, allowing, e.g. "ta %g0 + 15" to be rendered, more readably, as "ta 15", ignoring the %g0 register. This is per the sparc v8 and v9 manuals.

Check-in includes many extra unit tests to check this works correctly on both V8 and V9 Sparc processors.

Code Reviewed at http://reviews.llvm.org/D17960.

llvm-svn: 263044

1 files changed, 47 insertions, 0 deletions

diff --git a/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp b/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp
index 44d35764003..1dea379e14e 100644
--- a/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp
+++ b/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp
@@ -311,6 +311,8 @@ static DecodeStatus DecodeReturn(MCInst &MI, unsigned insn, uint64_t Address,
                                  const void *Decoder);
 static DecodeStatus DecodeSWAP(MCInst &Inst, unsigned insn, uint64_t Address,
                                const void *Decoder);
+static DecodeStatus DecodeTRAP(MCInst &Inst, unsigned insn, uint64_t Address,
+                               const void *Decoder);
 
 #include "SparcGenDisassemblerTables.inc"
 
@@ -346,6 +348,18 @@ DecodeStatus SparcDisassembler::getInstruction(MCInst &Instr, uint64_t &Size,
     return MCDisassembler::Fail;
 
   // Calling the auto-generated decoder function.
+  
+  if (STI.getFeatureBits()[Sparc::FeatureV9])
+  {
+    Result = decodeInstruction(DecoderTableSparcV932, Instr, Insn, Address, this, STI);
+  }
+  else
+  {
+    Result = decodeInstruction(DecoderTableSparcV832, Instr, Insn, Address, this, STI);      
+  }
+  if (Result != MCDisassembler::Fail)
+    return Result;
+  
   Result =
       decodeInstruction(DecoderTableSparc32, Instr, Insn, Address, this, STI);
 
@@ -619,3 +633,36 @@ static DecodeStatus DecodeSWAP(MCInst &MI, unsigned insn, uint64_t Address,
 
   return MCDisassembler::Success;
 }
+
+static DecodeStatus DecodeTRAP(MCInst &MI, unsigned insn, uint64_t Address,
+                               const void *Decoder) {
+
+  unsigned rs1 = fieldFromInstruction(insn, 14, 5);
+  unsigned isImm = fieldFromInstruction(insn, 13, 1);
+  unsigned cc =fieldFromInstruction(insn, 25, 4);
+  unsigned rs2 = 0;
+  unsigned imm7 = 0;
+  if (isImm)
+    imm7 = fieldFromInstruction(insn, 0, 7);
+  else
+    rs2 = fieldFromInstruction(insn, 0, 5);
+
+  // Decode RS1.
+  DecodeStatus status = DecodeIntRegsRegisterClass(MI, rs1, Address, Decoder);
+  if (status != MCDisassembler::Success)
+    return status;
+
+  // Decode RS1 | IMM7.
+  if (isImm)
+    MI.addOperand(MCOperand::createImm(imm7));
+  else {
+    status = DecodeIntRegsRegisterClass(MI, rs2, Address, Decoder);
+    if (status != MCDisassembler::Success)
+      return status;
+  }
+  
+  // Decode CC
+  MI.addOperand(MCOperand::createImm(cc));
+
+  return MCDisassembler::Success;
+}