Get rid of the middleman (ARMAlgorithm), which causes more trouble than the

abstraction it brings.  And also get rid of the atexit() handler, it does not
belong in the lib directory. :-)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100265 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 20 insertions, 40 deletions

diff --git a/lib/Target/ARM/Disassembler/ARMDisassemblerCore.cpp b/lib/Target/ARM/Disassembler/ARMDisassemblerCore.cpp
index eb67d754e2..db921ef0b6 100644
--- a/lib/Target/ARM/Disassembler/ARMDisassemblerCore.cpp
+++ b/lib/Target/ARM/Disassembler/ARMDisassemblerCore.cpp
@@ -8,8 +8,8 @@
 //===----------------------------------------------------------------------===//
 //
 // This file is part of the ARM Disassembler.
-// It contains code to represent the core concepts of Builder, Builder Factory,
-// as well as the Algorithm to solve the problem of disassembling an ARM instr.
+// It contains code to represent the core concepts of Builder and DisassembleFP
+// to solve the problem of disassembling an ARM instr.
 //
 //===----------------------------------------------------------------------===//
 
@@ -3127,40 +3127,12 @@ static const DisassembleFP FuncPtrs[] = {
   NULL
 };
 
-/// Algorithms - Algorithms stores a map from Format to ARMAlgorithm*.
-static std::vector<ARMAlgorithm*> Algorithms;
-
-/// DoCleanup - Do cleanup of Algorithms upon exit.
-void ARMAlgorithm::DoCleanup() {
-  for (unsigned i = 0; i < array_lengthof(FuncPtrs); ++i)
-    if (Algorithms[i])
-      delete Algorithms[i];
-}
-
-/// GetInstance - GetInstance returns an instance of ARMAlgorithm given the
-/// encoding Format.  API clients should not free up the returned instance.
-ARMAlgorithm *ARMAlgorithm::GetInstance(ARMFormat Format) {
-  /// Init the first time.
-  if (Algorithms.size() == 0) {
-    Algorithms.resize(array_lengthof(FuncPtrs));
-    for (unsigned i = 0, num = array_lengthof(FuncPtrs); i < num; ++i)
-      if (FuncPtrs[i])
-        Algorithms[i] = new ARMAlgorithm(FuncPtrs[i]);
-      else
-        Algorithms[i] = NULL;
-
-    // Register cleanup routine.
-    atexit(DoCleanup);
-  }
-  return Algorithms[Format];
-}
-
 /// BuildIt - BuildIt performs the build step for this ARM Basic MC Builder.
 /// The general idea is to set the Opcode for the MCInst, followed by adding
 /// the appropriate MCOperands to the MCInst.  ARM Basic MC Builder delegates
-/// to the Algo (ARM Disassemble Algorithm) object to perform Format-specific
-/// disassembly, followed by TryPredicateAndSBitModifier() to do
-/// PredicateOperand and OptionalDefOperand which follow the Dst/Src Operands.
+/// to the Format-specific disassemble function for disassembly, followed by
+/// TryPredicateAndSBitModifier() to do PredicateOperand and OptionalDefOperand
+/// which follow the Dst/Src Operands.
 bool ARMBasicMCBuilder::BuildIt(MCInst &MI, uint32_t insn) {
   // Stage 1 sets the Opcode.
   MI.setOpcode(Opcode);
@@ -3168,9 +3140,12 @@ bool ARMBasicMCBuilder::BuildIt(MCInst &MI, uint32_t insn) {
   if (NumOps == 0)
     return true;
 
-  // Stage 2 calls the ARM Disassembly Algorithm to build the operand list.
+  // Stage 2 calls the format-specific disassemble function to build the operand
+  // list.
+  if (Disasm == NULL)
+    return false;
   unsigned NumOpsAdded = 0;
-  bool OK = Algo.Solve(MI, Opcode, insn, NumOps, NumOpsAdded, this);
+  bool OK = (*Disasm)(MI, Opcode, insn, NumOps, NumOpsAdded, this);
 
   if (!OK) return false;
   if (NumOpsAdded >= NumOps)
@@ -3256,6 +3231,15 @@ bool ARMBasicMCBuilder::RunBuildAfterHook(bool Status, MCInst &MI,
   return Status;
 }
 
+/// Opcode, Format, and NumOperands make up an ARM Basic MCBuilder.
+ARMBasicMCBuilder::ARMBasicMCBuilder(unsigned opc, ARMFormat format,
+                                     unsigned short num)
+  : Opcode(opc), Format(format), NumOps(num), SP(0) {
+  unsigned Idx = (unsigned)format;
+  assert(Idx < (array_lengthof(FuncPtrs) - 1) && "Unknown format");
+  Disasm = FuncPtrs[Idx];
+}
+
 /// CreateMCBuilder - Return an ARMBasicMCBuilder that can build up the MC
 /// infrastructure of an MCInst given the Opcode and Format of the instr.
 /// Return NULL if it fails to create/return a proper builder.  API clients
@@ -3263,10 +3247,6 @@ bool ARMBasicMCBuilder::RunBuildAfterHook(bool Status, MCInst &MI,
 /// performed by the API clients to improve performance.
 ARMBasicMCBuilder *llvm::CreateMCBuilder(unsigned Opcode, ARMFormat Format) {
 
-  ARMAlgorithm *Algo = ARMAlgorithm::GetInstance(Format);
-  if (!Algo)
-    return NULL;
-
   return new ARMBasicMCBuilder(Opcode, Format,
-                               ARMInsts[Opcode].getNumOperands(), *Algo);
+                               ARMInsts[Opcode].getNumOperands());
 }