1 files changed, 207 insertions, 0 deletions
diff --git a/llvm/utils/TableGen/AsmWriterInst.cpp b/llvm/utils/TableGen/AsmWriterInst.cpp
new file mode 100644
index 000000000000..c26e0e421183
--- /dev/null
+++ b/llvm/utils/TableGen/AsmWriterInst.cpp
@@ -0,0 +1,207 @@
+//===- AsmWriterInst.h - Classes encapsulating a printable inst -----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// These classes implement a parser for assembly strings.
+//
+//===----------------------------------------------------------------------===//
+
+#include "AsmWriterInst.h"
+#include "CodeGenTarget.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/TableGen/Error.h"
+#include "llvm/TableGen/Record.h"
+
+using namespace llvm;
+
+static bool isIdentChar(char C) {
+  return (C >= 'a' && C <= 'z') ||
+  (C >= 'A' && C <= 'Z') ||
+  (C >= '0' && C <= '9') ||
+  C == '_';
+}
+
+std::string AsmWriterOperand::getCode(bool PassSubtarget) const {
+  if (OperandType == isLiteralTextOperand) {
+    if (Str.size() == 1)
+      return "O << '" + Str + "';";
+    return "O << \"" + Str + "\";";
+  }
+
+  if (OperandType == isLiteralStatementOperand)
+    return Str;
+
+  std::string Result = Str + "(MI";
+  if (MIOpNo != ~0U)
+    Result += ", " + utostr(MIOpNo);
+  if (PassSubtarget)
+    Result += ", STI";
+  Result += ", O";
+  if (!MiModifier.empty())
+    Result += ", \"" + MiModifier + '"';
+  return Result + ");";
+}
+
+/// ParseAsmString - Parse the specified Instruction's AsmString into this
+/// AsmWriterInst.
+///
+AsmWriterInst::AsmWriterInst(const CodeGenInstruction &CGI, unsigned CGIIndex,
+                             unsigned Variant)
+    : CGI(&CGI), CGIIndex(CGIIndex) {
+
+  // NOTE: Any extensions to this code need to be mirrored in the
+  // AsmPrinter::printInlineAsm code that executes as compile time (assuming
+  // that inline asm strings should also get the new feature)!
+  std::string AsmString = CGI.FlattenAsmStringVariants(CGI.AsmString, Variant);
+  std::string::size_type LastEmitted = 0;
+  while (LastEmitted != AsmString.size()) {
+    std::string::size_type DollarPos =
+      AsmString.find_first_of("$\\", LastEmitted);
+    if (DollarPos == std::string::npos) DollarPos = AsmString.size();
+
+    // Emit a constant string fragment.
+    if (DollarPos != LastEmitted) {
+      for (; LastEmitted != DollarPos; ++LastEmitted)
+        switch (AsmString[LastEmitted]) {
+          case '\n':
+            AddLiteralString("\\n");
+            break;
+          case '\t':
+            AddLiteralString("\\t");
+            break;
+          case '"':
+            AddLiteralString("\\\"");
+            break;
+          case '\\':
+            AddLiteralString("\\\\");
+            break;
+          default:
+            AddLiteralString(std::string(1, AsmString[LastEmitted]));
+            break;
+        }
+    } else if (AsmString[DollarPos] == '\\') {
+      if (DollarPos+1 != AsmString.size()) {
+        if (AsmString[DollarPos+1] == 'n') {
+          AddLiteralString("\\n");
+        } else if (AsmString[DollarPos+1] == 't') {
+          AddLiteralString("\\t");
+        } else if (std::string("${|}\\").find(AsmString[DollarPos+1])
+                   != std::string::npos) {
+          AddLiteralString(std::string(1, AsmString[DollarPos+1]));
+        } else {
+          PrintFatalError(
+              CGI.TheDef->getLoc(),
+              "Non-supported escaped character found in instruction '" +
+                  CGI.TheDef->getName() + "'!");
+        }
+        LastEmitted = DollarPos+2;
+        continue;
+      }
+    } else if (DollarPos+1 != AsmString.size() &&
+               AsmString[DollarPos+1] == '$') {
+      AddLiteralString("$");  // "$$" -> $
+      LastEmitted = DollarPos+2;
+    } else {
+      // Get the name of the variable.
+      std::string::size_type VarEnd = DollarPos+1;
+
+      // handle ${foo}bar as $foo by detecting whether the character following
+      // the dollar sign is a curly brace.  If so, advance VarEnd and DollarPos
+      // so the variable name does not contain the leading curly brace.
+      bool hasCurlyBraces = false;
+      if (VarEnd < AsmString.size() && '{' == AsmString[VarEnd]) {
+        hasCurlyBraces = true;
+        ++DollarPos;
+        ++VarEnd;
+      }
+
+      while (VarEnd < AsmString.size() && isIdentChar(AsmString[VarEnd]))
+        ++VarEnd;
+      StringRef VarName(AsmString.data()+DollarPos+1, VarEnd-DollarPos-1);
+
+      // Modifier - Support ${foo:modifier} syntax, where "modifier" is passed
+      // into printOperand.  Also support ${:feature}, which is passed into
+      // PrintSpecial.
+      std::string Modifier;
+
+      // In order to avoid starting the next string at the terminating curly
+      // brace, advance the end position past it if we found an opening curly
+      // brace.
+      if (hasCurlyBraces) {
+        if (VarEnd >= AsmString.size())
+          PrintFatalError(
+              CGI.TheDef->getLoc(),
+              "Reached end of string before terminating curly brace in '" +
+                  CGI.TheDef->getName() + "'");
+
+        // Look for a modifier string.
+        if (AsmString[VarEnd] == ':') {
+          ++VarEnd;
+          if (VarEnd >= AsmString.size())
+            PrintFatalError(
+                CGI.TheDef->getLoc(),
+                "Reached end of string before terminating curly brace in '" +
+                    CGI.TheDef->getName() + "'");
+
+          std::string::size_type ModifierStart = VarEnd;
+          while (VarEnd < AsmString.size() && isIdentChar(AsmString[VarEnd]))
+            ++VarEnd;
+          Modifier = std::string(AsmString.begin()+ModifierStart,
+                                 AsmString.begin()+VarEnd);
+          if (Modifier.empty())
+            PrintFatalError(CGI.TheDef->getLoc(),
+                            "Bad operand modifier name in '" +
+                                CGI.TheDef->getName() + "'");
+        }
+
+        if (AsmString[VarEnd] != '}')
+          PrintFatalError(
+              CGI.TheDef->getLoc(),
+              "Variable name beginning with '{' did not end with '}' in '" +
+                  CGI.TheDef->getName() + "'");
+        ++VarEnd;
+      }
+      if (VarName.empty() && Modifier.empty())
+        PrintFatalError(CGI.TheDef->getLoc(),
+                        "Stray '$' in '" + CGI.TheDef->getName() +
+                            "' asm string, maybe you want $$?");
+
+      if (VarName.empty()) {
+        // Just a modifier, pass this into PrintSpecial.
+        Operands.emplace_back("PrintSpecial", ~0U, Modifier);
+      } else {
+        // Otherwise, normal operand.
+        unsigned OpNo = CGI.Operands.getOperandNamed(VarName);
+        CGIOperandList::OperandInfo OpInfo = CGI.Operands[OpNo];
+
+        unsigned MIOp = OpInfo.MIOperandNo;
+        Operands.emplace_back(OpInfo.PrinterMethodName, MIOp, Modifier);
+      }
+      LastEmitted = VarEnd;
+    }
+  }
+
+  Operands.emplace_back("return;", AsmWriterOperand::isLiteralStatementOperand);
+}
+
+/// MatchesAllButOneOp - If this instruction is exactly identical to the
+/// specified instruction except for one differing operand, return the differing
+/// operand number.  If more than one operand mismatches, return ~1, otherwise
+/// if the instructions are identical return ~0.
+unsigned AsmWriterInst::MatchesAllButOneOp(const AsmWriterInst &Other)const{
+  if (Operands.size() != Other.Operands.size()) return ~1;
+
+  unsigned MismatchOperand = ~0U;
+  for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
+    if (Operands[i] != Other.Operands[i]) {
+      if (MismatchOperand != ~0U)  // Already have one mismatch?
+        return ~1U;
+      MismatchOperand = i;
+    }
+  }
+  return MismatchOperand;
+}