From 6b5252db2db5eeeadec4602329ac56beb6dea54a Mon Sep 17 00:00:00 2001
From: Jim Grosbach <grosbach@apple.com>
Date: Sat, 30 Oct 2010 00:37:59 +0000
Subject: [PATCH] Encode the register list operands for ARM mode LDM/STM
 instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117753 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/ARM/ARMCodeEmitter.cpp   |  3 +++
 lib/Target/ARM/ARMInstrFormats.td   |  4 ++++
 lib/Target/ARM/ARMInstrInfo.td      |  1 +
 lib/Target/ARM/ARMMCCodeEmitter.cpp | 15 +++++++++++++++
 4 files changed, 23 insertions(+)

diff --git a/lib/Target/ARM/ARMCodeEmitter.cpp b/lib/Target/ARM/ARMCodeEmitter.cpp
index f5d63a8ac04..f1c54b9e173 100644
--- a/lib/Target/ARM/ARMCodeEmitter.cpp
+++ b/lib/Target/ARM/ARMCodeEmitter.cpp
@@ -197,6 +197,9 @@ namespace {
     unsigned getNEONVcvtImm32OpValue(const MachineInstr &MI, unsigned Op)
       const { return 0; }
 
+    unsigned getRegisterListOpValue(const MachineInstr &MI, unsigned Op)
+      const { return 0; }
+
     /// getMovi32Value - Return binary encoding of operand for movw/movt. If the
     /// machine operand requires relocation, record the relocation and return
     /// zero.
diff --git a/lib/Target/ARM/ARMInstrFormats.td b/lib/Target/ARM/ARMInstrFormats.td
index 141bc1a1286..91789dae608 100644
--- a/lib/Target/ARM/ARMInstrFormats.td
+++ b/lib/Target/ARM/ARMInstrFormats.td
@@ -937,17 +937,21 @@ class AXI4ld<dag oops, dag iops, IndexMode im, Format f, InstrItinClass itin,
              string asm, string cstr, list<dag> pattern>
   : XI<oops, iops, AddrMode4, Size4Bytes, im, f, itin,
        asm, cstr, pattern> {
+  bits<16> dsts;
   let Inst{20}    = 1; // L bit
   let Inst{22}    = 0; // S bit
   let Inst{27-25} = 0b100;
+  let Inst{15-0}  = dsts;
 }
 class AXI4st<dag oops, dag iops, IndexMode im, Format f, InstrItinClass itin,
              string asm, string cstr, list<dag> pattern>
   : XI<oops, iops, AddrMode4, Size4Bytes, im, f, itin,
        asm, cstr, pattern> {
+  bits<16> srcs;
   let Inst{20}    = 0; // L bit
   let Inst{22}    = 0; // S bit
   let Inst{27-25} = 0b100;
+  let Inst{15-0}  = srcs;
 }
 
 // Unsigned multiply, multiply-accumulate instructions.
diff --git a/lib/Target/ARM/ARMInstrInfo.td b/lib/Target/ARM/ARMInstrInfo.td
index 0a390002318..4497a92cceb 100644
--- a/lib/Target/ARM/ARMInstrInfo.td
+++ b/lib/Target/ARM/ARMInstrInfo.td
@@ -279,6 +279,7 @@ def brtarget : Operand<OtherVT>;
 
 // A list of registers separated by comma. Used by load/store multiple.
 def reglist : Operand<i32> {
+  string EncoderMethod = "getRegisterListOpValue";
   let PrintMethod = "printRegisterList";
 }
 
diff --git a/lib/Target/ARM/ARMMCCodeEmitter.cpp b/lib/Target/ARM/ARMMCCodeEmitter.cpp
index 8693ec3fd1c..b74fa73d650 100644
--- a/lib/Target/ARM/ARMMCCodeEmitter.cpp
+++ b/lib/Target/ARM/ARMMCCodeEmitter.cpp
@@ -98,6 +98,9 @@ public:
 
   unsigned getBitfieldInvertedMaskOpValue(const MCInst &MI, unsigned Op) const;
 
+  unsigned getRegisterListOpValue(const MCInst &MI, unsigned Op) const;
+
+
   unsigned getNumFixupKinds() const {
     assert(0 && "ARMMCCodeEmitter::getNumFixupKinds() not yet implemented.");
     return 0;
@@ -285,6 +288,18 @@ unsigned ARMMCCodeEmitter::getBitfieldInvertedMaskOpValue(const MCInst &MI,
   return lsb | (msb << 5);
 }
 
+unsigned ARMMCCodeEmitter::getRegisterListOpValue(const MCInst &MI,
+                                                  unsigned Op) const {
+  // Convert a list of GPRs into a bitfield (R0 -> bit 0). For each
+  // register in the list, set the corresponding bit.
+  unsigned Binary = 0;
+  for (unsigned i = Op; i < MI.getNumOperands(); ++i) {
+    unsigned regno = getARMRegisterNumbering(MI.getOperand(i).getReg());
+    Binary |= 1 << regno;
+  }
+  return Binary;
+}
+
 void ARMMCCodeEmitter::
 EncodeInstruction(const MCInst &MI, raw_ostream &OS,
                   SmallVectorImpl<MCFixup> &Fixups) const {