[mips] Add range checks and transformation to octeon instructions in AsmParser.

This patch adds range checks to the immediate operands of octeon
instructions in the AsmParser. Like gas, it applies the following
transformations if the immediate is to large:

bbit0 $8, 42, foo => bbit032 $8, 10, foo
bbit1 $8, 46, foo => bbit132 $8, 14, foo
cins $8, $31, 32, 31 => cins32 $8, $31, 0, 31
exts $7, $4, 54, 9 => exts32 $7, $4, 22, 9

Reviewed By: dsanders

Differential Revision: http://reviews.llvm.org/D7080


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227225 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/Mips/AsmParser/MipsAsmParser.cpp

@@ -382,6 +382,9 @@ public:
   bool hasMips64r6() const {
     return (STI.getFeatureBits() & Mips::FeatureMips64r6);
   }
+  bool hasCnMips() const {
+    return (STI.getFeatureBits() & Mips::FeatureCnMips);
+  }
   bool hasDSP() const { return (STI.getFeatureBits() & Mips::FeatureDSP); }
   bool hasDSPR2() const { return (STI.getFeatureBits() & Mips::FeatureDSPR2); }
   bool hasMSA() const { return (STI.getFeatureBits() & Mips::FeatureMSA); }
@@ -1168,6 +1171,13 @@ bool MipsAsmParser::processInstruction(MCInst &Inst, SMLoc IDLoc,
     switch (Opcode) {
     default:
       break;
+    case Mips::BBIT0:
+    case Mips::BBIT032:
+    case Mips::BBIT1:
+    case Mips::BBIT132:
+      assert(hasCnMips() && "instruction only valid for octeon cpus");
+      // Fall through
+
     case Mips::BEQ:
     case Mips::BNE:
     case Mips::BEQ_MM:
@@ -1230,6 +1240,74 @@ bool MipsAsmParser::processInstruction(MCInst &Inst, SMLoc IDLoc,
                                                       "nop instruction");
   }
 
+  if (hasCnMips()) {
+    const unsigned Opcode = Inst.getOpcode();
+    MCOperand Opnd;
+    int Imm;
+
+    switch (Opcode) {
+      default:
+        break;
+
+      case Mips::BBIT0:
+      case Mips::BBIT032:
+      case Mips::BBIT1:
+      case Mips::BBIT132:
+        assert(MCID.getNumOperands() == 3 && "unexpected number of operands");
+        // The offset is handled above
+        Opnd = Inst.getOperand(1);
+        if (!Opnd.isImm())
+          return Error(IDLoc, "expected immediate operand kind");
+        Imm = Opnd.getImm();
+        if (Imm < 0 || Imm > (Opcode == Mips::BBIT0 ||
+                              Opcode == Mips::BBIT1 ? 63 : 31))
+          return Error(IDLoc, "immediate operand value out of range");
+        if (Imm > 31) {
+          Inst.setOpcode(Opcode == Mips::BBIT0 ? Mips::BBIT032
+                                               : Mips::BBIT132);
+          Inst.getOperand(1).setImm(Imm - 32);
+        }
+        break;
+
+      case Mips::CINS:
+      case Mips::CINS32:
+      case Mips::EXTS:
+      case Mips::EXTS32:
+        assert(MCID.getNumOperands() == 4 && "unexpected number of operands");
+        // Check length
+        Opnd = Inst.getOperand(3);
+        if (!Opnd.isImm())
+          return Error(IDLoc, "expected immediate operand kind");
+        Imm = Opnd.getImm();
+        if (Imm < 0 || Imm > 31)
+          return Error(IDLoc, "immediate operand value out of range");
+        // Check position
+        Opnd = Inst.getOperand(2);
+        if (!Opnd.isImm())
+          return Error(IDLoc, "expected immediate operand kind");
+        Imm = Opnd.getImm();
+        if (Imm < 0 || Imm > (Opcode == Mips::CINS ||
+                              Opcode == Mips::EXTS ? 63 : 31))
+          return Error(IDLoc, "immediate operand value out of range");
+        if (Imm > 31) {
+          Inst.setOpcode(Opcode == Mips::CINS ? Mips::CINS32 : Mips::EXTS32);
+          Inst.getOperand(2).setImm(Imm - 32);
+        }
+        break;
+
+      case Mips::SEQi:
+      case Mips::SNEi:
+        assert(MCID.getNumOperands() == 3 && "unexpected number of operands");
+        Opnd = Inst.getOperand(2);
+        if (!Opnd.isImm())
+          return Error(IDLoc, "expected immediate operand kind");
+        Imm = Opnd.getImm();
+        if (!isInt<10>(Imm))
+          return Error(IDLoc, "immediate operand value out of range");
+        break;
+    }
+  }
+
   if (MCID.hasDelaySlot() && AssemblerOptions.back()->isReorder()) {
     // If this instruction has a delay slot and .set reorder is active,
     // emit a NOP after it.

test/MC/Mips/octeon-instructions.s

@@ -5,12 +5,16 @@
 # CHECK: baddu $2, $2, $3             # encoding: [0x70,0x43,0x10,0x28]
 # CHECK: bbit0 $19, 22, foo           # encoding: [0xca,0x76,A,A]
 # CHECK: bbit032 $fp, 11, foo         # encoding: [0xdb,0xcb,A,A]
+# CHECK: bbit032 $8, 10, foo          # encoding: [0xd9,0x0a,A,A]
 # CHECK: bbit1 $3, 31, foo            # encoding: [0xe8,0x7f,A,A]
 # CHECK: bbit132 $24, 10, foo         # encoding: [0xfb,0x0a,A,A]
+# CHECK: bbit132 $14, 14, foo         # encoding: [0xf9,0xce,A,A]
 # CHECK: cins  $25, $10, 22, 2        # encoding: [0x71,0x59,0x15,0xb2]
 # CHECK: cins  $9, $9, 17, 29         # encoding: [0x71,0x29,0xec,0x72]
 # CHECK: cins32 $15, $2, 18, 8        # encoding: [0x70,0x4f,0x44,0xb3]
 # CHECK: cins32 $22, $22, 9, 22       # encoding: [0x72,0xd6,0xb2,0x73]
+# CHECK: cins32 $24, $ra, 0, 31       # encoding: [0x73,0xf8,0xf8,0x33]
+# CHECK: cins32 $15, $15, 5, 5        # encoding: [0x71,0xef,0x29,0x73]
 # CHECK: dmul  $9, $6, $7             # encoding: [0x70,0xc7,0x48,0x03]
 # CHECK: dmul  $19, $24, $25          # encoding: [0x73,0x19,0x98,0x03]
 # CHECK: dmul  $9, $9, $6             # encoding: [0x71,0x26,0x48,0x03]
@@ -22,6 +26,8 @@
 # CHECK: exts  $15, $15, 17, 6        # encoding: [0x71,0xef,0x34,0x7a]
 # CHECK: exts32 $4, $13, 10, 8        # encoding: [0x71,0xa4,0x42,0xbb]
 # CHECK: exts32 $15, $15, 11, 20      # encoding: [0x71,0xef,0xa2,0xfb]
+# CHECK: exts32 $7, $4, 22, 9         # encoding: [0x70,0x87,0x4d,0xbb]
+# CHECK: exts32 $25, $25, 5, 25       # encoding: [0x73,0x39,0xc9,0x7b]
 # CHECK: mtm0  $15                    # encoding: [0x71,0xe0,0x00,0x08]
 # CHECK: mtm1  $16                    # encoding: [0x72,0x00,0x00,0x0c]
 # CHECK: mtm2  $17                    # encoding: [0x72,0x20,0x00,0x0d]
@@ -56,12 +62,16 @@ foo:
   baddu $2, $3
   bbit0 $19, 22, foo
   bbit032 $30, 11, foo
+  bbit0 $8, 42, foo
   bbit1 $3, 31, foo
   bbit132 $24, 10, foo
+  bbit1 $14, 46, foo
   cins  $25, $10, 22, 2
   cins  $9, 17, 29
   cins32 $15, $2, 18, 8
   cins32 $22, 9, 22
+  cins  $24, $31, 32, 31
+  cins  $15, 37, 5
   dmul  $9, $6, $7
   dmul  $19, $24, $25
   dmul  $9, $6
@@ -73,6 +83,8 @@ foo:
   exts  $15, 17, 6
   exts32 $4, $13, 10, 8
   exts32 $15, 11, 20
+  exts  $7, $4, 54, 9
+  exts  $25, 37, 25
   mtm0  $15
   mtm1  $16
   mtm2  $17