From: Owen Anderson <resistor@mac.com>
Date: Wed, 10 Aug 2011 19:01:10 +0000 (+0000)
Subject: Add initial support for decoding NEON instructions in Thumb2 mode.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=8533ebad6f6e407215497ca50771f323058f5576;p=oota-llvm.git

Add initial support for decoding NEON instructions in Thumb2 mode.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137236 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/ARM/ARMInstrFormats.td b/lib/Target/ARM/ARMInstrFormats.td
index b8d7b99d5a8..d7446ffe1aa 100644
--- a/lib/Target/ARM/ARMInstrFormats.td
+++ b/lib/Target/ARM/ARMInstrFormats.td
@@ -1608,7 +1608,7 @@ class NeonI<dag oops, dag iops, AddrMode am, IndexMode im, Format f,
   let AsmString = !strconcat(opc, "${p}", ".", dt, "\t", asm);
   let Pattern = pattern;
   list<Predicate> Predicates = [HasNEON];
-  let DecoderNamespace = "NEON";
+  let DecoderNamespace = "NEONData";
 }
 
 // Same as NeonI except it does not have a "data type" specifier.
@@ -1621,7 +1621,7 @@ class NeonXI<dag oops, dag iops, AddrMode am, IndexMode im, Format f,
   let AsmString = !strconcat(opc, "${p}", "\t", asm);
   let Pattern = pattern;
   list<Predicate> Predicates = [HasNEON];
-  let DecoderNamespace = "NEON";
+  let DecoderNamespace = "NEONData";
 }
 
 class NLdSt<bit op23, bits<2> op21_20, bits<4> op11_8, bits<4> op7_4,
@@ -1636,6 +1636,7 @@ class NLdSt<bit op23, bits<2> op21_20, bits<4> op11_8, bits<4> op7_4,
   let Inst{7-4}   = op7_4;
 
   let PostEncoderMethod = "NEONThumb2LoadStorePostEncoder";
+  let DecoderNamespace = "NEONLoadStore";
 
   bits<5> Vd;
   bits<6> Rn;
@@ -1911,6 +1912,7 @@ class NVLaneOp<bits<8> opcod1, bits<4> opcod2, bits<2> opcod3,
   list<Predicate> Predicates = [HasNEON];
 
   let PostEncoderMethod = "NEONThumb2DupPostEncoder";
+  let DecoderNamespace = "NEONDup";
 
   bits<5> V;
   bits<4> R;
diff --git a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp
index c9684e1f81c..b6bfece1b52 100644
--- a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp
+++ b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp
@@ -249,12 +249,32 @@ bool ARMDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
   }
 
   MI.clear();
-  result = decodeNEONInstruction32(MI, insn, Address, this);
+  result = decodeNEONDataInstruction32(MI, insn, Address, this);
   if (result) {
+    Size = 4;
     // Add a fake predicate operand, because we share these instruction
     // definitions with Thumb2 where these instructions are predicable.
     if (!DecodePredicateOperand(MI, 0xE, Address, this)) return false;
+    return true;
+  }
+
+  MI.clear();
+  result = decodeNEONLoadStoreInstruction32(MI, insn, Address, this);
+  if (result) {
     Size = 4;
+    // Add a fake predicate operand, because we share these instruction
+    // definitions with Thumb2 where these instructions are predicable.
+    if (!DecodePredicateOperand(MI, 0xE, Address, this)) return false;
+    return true;
+  }
+
+  MI.clear();
+  result = decodeNEONDupInstruction32(MI, insn, Address, this);
+  if (result) {
+    Size = 4;
+    // Add a fake predicate operand, because we share these instruction
+    // definitions with Thumb2 where these instructions are predicable.
+    if (!DecodePredicateOperand(MI, 0xE, Address, this)) return false;
     return true;
   }
 
@@ -433,6 +453,14 @@ bool ThumbDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
     return true;
   }
 
+  MI.clear();
+  result = decodeCommonInstruction32(MI, insn32, Address, this);
+  if (result) {
+    Size = 4;
+    AddThumbPredicate(MI);
+    return true;
+  }
+
   MI.clear();
   result = decodeVFPInstruction32(MI, insn32, Address, this);
   if (result) {
@@ -442,7 +470,29 @@ bool ThumbDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
   }
 
   MI.clear();
-  result = decodeCommonInstruction32(MI, insn32, Address, this);
+  if (fieldFromInstruction32(insn32, 24, 4) == 0xF) {
+    uint32_t NEONDataInsn = insn32;
+    NEONDataInsn &= 0xF0FFFFFF; // Clear bits 27-24
+    NEONDataInsn |= (NEONDataInsn & 0x10000000) >> 4; // Move bit 28 to bit 24
+    NEONDataInsn |= 0x12000000; // Set bits 28 and 25
+    result = decodeNEONDataInstruction32(MI, NEONDataInsn, Address, this);
+    if (result) {
+      Size = 4;
+      AddThumbPredicate(MI);
+      return true;
+    }
+  }
+
+  MI.clear();
+  result = decodeNEONLoadStoreInstruction32(MI, insn32, Address, this);
+  if (result) {
+    Size = 4;
+    AddThumbPredicate(MI);
+    return true;
+  }
+
+  MI.clear();
+  result = decodeNEONDupInstruction32(MI, insn32, Address, this);
   if (result) {
     Size = 4;
     AddThumbPredicate(MI);
diff --git a/test/MC/Disassembler/ARM/thumb-tests.txt b/test/MC/Disassembler/ARM/thumb-tests.txt
index 0d55bb795c7..e7655e33088 100644
--- a/test/MC/Disassembler/ARM/thumb-tests.txt
+++ b/test/MC/Disassembler/ARM/thumb-tests.txt
@@ -265,3 +265,6 @@
 
 # CHECK:	bne	#24
 0x0c 0xd1
+
+# CHECK:	vadd.f32	q0, q1, q2
+0x02 0xef 0x44 0x0d