Add accessors for inline assembly

Author: CodaFi

Sources/LLVM/IRBuilder.swift

@@ -1599,11 +1599,26 @@ extension IRBuilder {
   ///
   /// - returns: A representation of the newly created inline assembly
   ///   expression.
-  public func buildInlineAssembly(_ asm: String, type: FunctionType, constraints: String = "", hasSideEffects: Bool = true, needsAlignedStack: Bool = true) -> IRValue {
-    return LLVMConstInlineAsm(type.asLLVM(), asm, constraints, hasSideEffects.llvm, needsAlignedStack.llvm)
+  public func buildInlineAssembly(
+    _ asm: String, dialect: InlineAssemblyDialect, type: FunctionType,
+    constraints: String = "",
+    hasSideEffects: Bool = true, needsAlignedStack: Bool = true
+  ) -> IRValue {
+    var asm = asm.utf8CString
+    var constraints = constraints.utf8CString
+    return asm.withUnsafeMutableBufferPointer { asm in
+      return constraints.withUnsafeMutableBufferPointer { constraints in
+        return LLVMGetInlineAsm(type.asLLVM(),
+                                asm.baseAddress, asm.count,
+                                constraints.baseAddress, constraints.count,
+                                hasSideEffects.llvm, needsAlignedStack.llvm,
+                                dialect.llvm)
+      }
+    }
   }
 }
 
+
 private func lowerVector(_ type: IRType) -> IRType {
     guard let vectorType = type as? VectorType else {
         return type

Sources/LLVM/Module.swift

@@ -119,6 +119,18 @@ public final class Module: CustomStringConvertible {
     }
   }
 
+  /// Retrieves the inline assembly for this module, if any.
+  public var inlineAssembly: String {
+    get {
+      var length: Int = 0
+      guard let id = LLVMGetModuleInlineAsm(llvm, &length) else { return "" }
+      return String(cString: id)
+    }
+    set {
+      LLVMSetModuleInlineAsm2(llvm, newValue, newValue.utf8.count)
+    }
+  }
+
   /// Print a representation of a module to a file at the given path.
   ///
   /// If the provided path is not suitable for writing, this function will throw
@@ -430,6 +442,15 @@ extension Module {
   public func addAlias(name: String, to aliasee: IRGlobal, type: IRType) -> Alias {
     return Alias(llvm: LLVMAddAlias(llvm, type.asLLVM(), aliasee.asLLVM(), name))
   }
+
+  /// Append to the module-scope inline assembly blocks.
+  ///
+  /// A trailing newline is added if the given string doesn't have one.
+  ///
+  /// - parameter asm: The inline assembly expression template string.
+  public func appendInlineAssembly(_ asm: String) {
+    LLVMAppendModuleInlineAsm(llvm, asm, asm.count)
+  }
 }
 
 // MARK: Module Flags

Sources/LLVM/Operation.swift

@@ -51,16 +51,16 @@ public enum IntPredicate {
   /// less than or equal to the second.
   case signedLessThanOrEqual
 
-  static let predicateMapping: [IntPredicate: LLVMIntPredicate] = [
+  private static let predicateMapping: [IntPredicate: LLVMIntPredicate] = [
     .equal: LLVMIntEQ, .notEqual: LLVMIntNE, .unsignedGreaterThan: LLVMIntUGT,
     .unsignedGreaterThanOrEqual: LLVMIntUGE, .unsignedLessThan: LLVMIntULT,
     .unsignedLessThanOrEqual: LLVMIntULE, .signedGreaterThan: LLVMIntSGT,
     .signedGreaterThanOrEqual: LLVMIntSGE, .signedLessThan: LLVMIntSLT,
     .signedLessThanOrEqual: LLVMIntSLE,
-    ]
+  ]
 
   /// Retrieves the corresponding `LLVMIntPredicate`.
-  public var llvm: LLVMIntPredicate {
+  var llvm: LLVMIntPredicate {
     return IntPredicate.predicateMapping[self]!
   }
 }
@@ -100,7 +100,7 @@ public enum RealPredicate {
   /// No comparison, always returns `true`.
   case `true`
 
-  static let predicateMapping: [RealPredicate: LLVMRealPredicate] = [
+  private static let predicateMapping: [RealPredicate: LLVMRealPredicate] = [
     .false: LLVMRealPredicateFalse, .orderedEqual: LLVMRealOEQ,
     .orderedGreaterThan: LLVMRealOGT, .orderedGreaterThanOrEqual: LLVMRealOGE,
     .orderedLessThan: LLVMRealOLT, .orderedLessThanOrEqual: LLVMRealOLE,
@@ -109,10 +109,10 @@ public enum RealPredicate {
     .unorderedGreaterThanOrEqual: LLVMRealUGE, .unorderedLessThan: LLVMRealULT,
     .unorderedLessThanOrEqual: LLVMRealULE, .unorderedNotEqual: LLVMRealUNE,
     .true: LLVMRealPredicateTrue,
-    ]
+  ]
 
   /// Retrieves the corresponding `LLVMRealPredicate`.
-  public var llvm: LLVMRealPredicate {
+  var llvm: LLVMRealPredicate {
     return RealPredicate.predicateMapping[self]!
   }
 }
@@ -207,7 +207,7 @@ public enum AtomicOrdering: Comparable {
   }
 
   /// Retrieves the corresponding `LLVMAtomicOrdering`.
-  public var llvm: LLVMAtomicOrdering {
+  var llvm: LLVMAtomicOrdering {
     return AtomicOrdering.orderingMapping[self]!
   }
 }
@@ -290,7 +290,7 @@ public enum AtomicReadModifyWriteOperation {
   /// ```
   case umin
 
-  static let atomicRMWMapping: [AtomicReadModifyWriteOperation: LLVMAtomicRMWBinOp] = [
+  private static let atomicRMWMapping: [AtomicReadModifyWriteOperation: LLVMAtomicRMWBinOp] = [
     .xchg: LLVMAtomicRMWBinOpXchg, .add: LLVMAtomicRMWBinOpAdd,
     .sub: LLVMAtomicRMWBinOpSub, .and: LLVMAtomicRMWBinOpAnd,
     .nand: LLVMAtomicRMWBinOpNand, .or: LLVMAtomicRMWBinOpOr,
@@ -300,7 +300,43 @@ public enum AtomicReadModifyWriteOperation {
   ]
 
   /// Retrieves the corresponding `LLVMAtomicRMWBinOp`.
-  public var llvm: LLVMAtomicRMWBinOp {
+  var llvm: LLVMAtomicRMWBinOp {
     return AtomicReadModifyWriteOperation.atomicRMWMapping[self]!
   }
 }
+
+/// Enumerates the dialects of inline assembly LLVM's parsers can handle.
+public enum InlineAssemblyDialect {
+  /// The dialect of assembly created at Bell Labs by AT&T.
+  ///
+  /// AT&T syntax differs from Intel syntax in a number of ways.  Notably:
+  ///
+  /// - The source operand is before the destination operand
+  /// - Immediate operands are prefixed by a dollar-sign (`$`)
+  /// - Register operands are preceded by a percent-sign (`%`)
+  /// - The size of memory operands is determined from the last character of the
+  ///   the opcode name.  Valid suffixes include `b` for "byte" (8-bit),
+  ///   `w` for "word" (16-bit), `l` for "long-word" (32-bit), and `q` for
+  ///   "quad-word" (64-bit) memory references
+  case att
+  /// The dialect of assembly created at Intel.
+  ///
+  /// Intel syntax differs from AT&T syntax in a number of ways.  Notably:
+  ///
+  /// - The destination operand is before the source operand
+  /// - Immediate and register operands have no prefix.
+  /// - Memory operands are annotated with their sizes. Valid annotations
+  ///   include `byte ptr` (8-bit), `word ptr` (16-bit), `dword ptr` (32-bit) and
+  ///   `qword ptr` (64-bit).
+  case intel
+
+  private static let dialectMapping: [InlineAssemblyDialect: LLVMInlineAsmDialect] = [
+    .att: LLVMInlineAsmDialectATT,
+    .intel: LLVMInlineAsmDialectIntel,
+  ]
+
+  /// Retrieves the corresponding `LLVMInlineAsmDialect`.
+  var llvm: LLVMInlineAsmDialect {
+    return InlineAssemblyDialect.dialectMapping[self]!
+  }
+}

Tests/LLVMTests/IRBuilderSpec.swift

@@ -23,6 +23,42 @@ class IRBuilderSpec : XCTestCase {
       module.dump()
     })
 
+    XCTAssert(fileCheckOutput(of: .stderr, withPrefixes: ["IRBUILDER-INLINE-ASM"]) {
+      // IRBUILDER-INLINE-ASM: ; ModuleID = '[[ModuleName:IRBuilderInlineAsmTest]]'
+      // IRBUILDER-INLINE-ASM-NEXT: source_filename = "[[ModuleName]]"
+      let module = Module(name: "IRBuilderInlineAsmTest")
+      let builder = IRBuilder(module: module)
+
+      // IRBUILDER-INLINE-ASM: module asm "i32 (i32) asm \22bswap $0\22, \22=r,r\22"
+      module.appendInlineAssembly("""
+      i32 (i32) asm "bswap $0", "=r,r"
+      """)
+      // IRBUILDER-INLINE-ASM-NEXT: %X = call i32 asm \22bswap $0\22, \22=r,r\22(i32 %Y)
+      module.appendInlineAssembly("""
+      %X = call i32 asm "bswap $0", "=r,r"(i32 %Y)
+      """)
+
+      // IRBUILDER-INLINE-ASM: @a = global i32 1
+      let g1 = builder.addGlobal("a", type: IntType.int32)
+      g1.initializer = Int32(1)
+
+      // IRBUILDER-INLINE-ASM: define void @main() {
+      let main = builder.addFunction("main",
+                                     type: FunctionType(argTypes: [],
+                                                        returnType: VoidType()))
+      // IRBUILDER-INLINE-ASM-NEXT: entry:
+      let entry = main.appendBasicBlock(named: "entry")
+      builder.positionAtEnd(of: entry)
+      let ty = FunctionType(argTypes: [ PointerType(pointee: IntType.int32) ], returnType: VoidType())
+      let emptyASM = builder.buildInlineAssembly("", dialect: .att, type: ty, constraints: "=r,0", hasSideEffects: true, needsAlignedStack: true)
+      // IRBUILDER-INLINE-ASM-NEXT: call void asm sideeffect alignstack "\00", "=r,0\00"(i32* @a)
+      _ = builder.buildCall(emptyASM, args: [ g1 ])
+      // IRBUILDER-INLINE-ASM-NEXT: ret void
+      builder.buildRetVoid()
+      // IRBUILDER-INLINE-ASM-NEXT: }
+      module.dump()
+    })
+
     // MARK: Arithmetic Instructions
 
     XCTAssert(fileCheckOutput(of: .stderr, withPrefixes: ["IRBUILDERARITH"]) {