From 0c2f9ee188b3ddb8d2d0b1803bd99d9b99b4c859 Mon Sep 17 00:00:00 2001
From: chhzh123 <hc676@cornell.edu>
Date: Wed, 16 Mar 2022 20:41:22 -0400
Subject: [PATCH] [Op][Backend][Binding] Add ReverseOp (Fix #42)

---
 include/hcl/Bindings/Python/hcl/build_ir.py | 10 ++++++++++
 include/hcl/Dialect/HeteroCLOps.td          |  9 +++++++++
 include/hcl/Dialect/Visitor.h               |  3 ++-
 lib/Translation/EmitHLSCpp.cpp              | 15 +++++++++++++++
 4 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/include/hcl/Bindings/Python/hcl/build_ir.py b/include/hcl/Bindings/Python/hcl/build_ir.py
index a292d2ba..0aaa4304 100644
--- a/include/hcl/Bindings/Python/hcl/build_ir.py
+++ b/include/hcl/Bindings/Python/hcl/build_ir.py
@@ -493,6 +493,11 @@ def __setitem__(self, indices, expr):
             indices = indices[0]
             return SetBitOp(self, indices, expr)
 
+    def reverse(self):
+        if not is_integer_type(self.dtype):
+            raise RuntimeError("Only integers can reverse the bits")
+        return BitReverseOp(self)
+
     def __nonzero__(self):
         raise RuntimeError(
             "1) Cannot use and / or / not operator to Expr, "
@@ -1057,6 +1062,11 @@ def __init__(self, val):
         )  # use the same op
 
 
+class BitReverseOp(UnaryOp):
+    def __init__(self, val):
+        super().__init__(hcl_d.BitReverseOp, val.dtype, val)
+
+
 class BitCastOp(UnaryOp):
     def __init__(self, dtype, val):
         super().__init__(arith.BitcastOp, dtype, val)
diff --git a/include/hcl/Dialect/HeteroCLOps.td b/include/hcl/Dialect/HeteroCLOps.td
index 5bf8dffb..72d4fdc3 100644
--- a/include/hcl/Dialect/HeteroCLOps.td
+++ b/include/hcl/Dialect/HeteroCLOps.td
@@ -441,4 +441,13 @@ def SetIntSliceOp : HeteroCL_Op<"set_slice"> {
     }];
 }
 
+def BitReverseOp : HeteroCL_Op<"bit_reverse", [SameOperandsAndResultType]> {
+    let summary = "reverse bits of an integer";
+    let arguments = (ins SignlessIntegerLike:$num);
+    let results = (outs SignlessIntegerLike:$result);
+    let assemblyFormat = [{
+        `(` $num `:` type($num) `)` attr-dict
+    }];
+}
+
 #endif // HCL_OPS
diff --git a/include/hcl/Dialect/Visitor.h b/include/hcl/Dialect/Visitor.h
index cbbc8855..c25378ea 100644
--- a/include/hcl/Dialect/Visitor.h
+++ b/include/hcl/Dialect/Visitor.h
@@ -61,7 +61,7 @@ class HLSCppVisitorBase {
             // Logical expressions.
             arith::XOrIOp, arith::AndIOp, arith::OrIOp, arith::ShLIOp,
             arith::ShRSIOp, arith::ShRUIOp, hcl::GetIntBitOp, hcl::SetIntBitOp,
-            hcl::GetIntSliceOp, hcl::SetIntSliceOp,
+            hcl::GetIntSliceOp, hcl::SetIntSliceOp, hcl::BitReverseOp,
             // Special operations.
             CallOp, ReturnOp, SelectOp, ConstantOp, arith::ConstantOp,
             arith::TruncIOp, arith::TruncFOp, arith::ExtUIOp, arith::ExtSIOp,
@@ -186,6 +186,7 @@ class HLSCppVisitorBase {
   HANDLE(hcl::SetIntBitOp);
   HANDLE(hcl::GetIntSliceOp);
   HANDLE(hcl::SetIntSliceOp);
+  HANDLE(hcl::BitReverseOp);
 
   // Special operations.
   HANDLE(CallOp);
diff --git a/lib/Translation/EmitHLSCpp.cpp b/lib/Translation/EmitHLSCpp.cpp
index 95b1478f..4576c1a4 100644
--- a/lib/Translation/EmitHLSCpp.cpp
+++ b/lib/Translation/EmitHLSCpp.cpp
@@ -285,6 +285,7 @@ class ModuleEmitter : public HCLEmitterBase {
   void emitSetBit(hcl::SetIntBitOp op);
   void emitGetSlice(hcl::GetIntSliceOp op);
   void emitSetSlice(hcl::SetIntSliceOp op);
+  void emitBitReverse(hcl::BitReverseOp op);
   void emitBitcast(arith::BitcastOp op);
 
   /// Top-level MLIR module emitter.
@@ -503,6 +504,9 @@ class ExprVisitor : public HLSCppVisitorBase<ExprVisitor, bool> {
   bool visitOp(hcl::SetIntBitOp op) { return emitter.emitSetBit(op), true; }
   bool visitOp(hcl::GetIntSliceOp op) { return emitter.emitGetSlice(op), true; }
   bool visitOp(hcl::SetIntSliceOp op) { return emitter.emitSetSlice(op), true; }
+  bool visitOp(hcl::BitReverseOp op) {
+    return emitter.emitBitReverse(op), true;
+  }
 
   /// Unary expressions.
   bool visitOp(math::AbsOp op) { return emitter.emitUnary(op, "abs"), true; }
@@ -1407,6 +1411,17 @@ void ModuleEmitter::emitSetSlice(hcl::SetIntSliceOp op) {
   emitInfoAndNewLine(op);
 }
 
+void ModuleEmitter::emitBitReverse(hcl::BitReverseOp op) {
+  indent();
+  Value result = op.getResult();
+  fixUnsignedType(result, op->hasAttr("unsigned"));
+  emitValue(result);
+  os << " = ";
+  emitValue(op.num());
+  os << ".reverse();";
+  emitInfoAndNewLine(op);
+}
+
 void ModuleEmitter::emitSelect(SelectOp op) {
   unsigned rank = emitNestedLoopHead(op.getResult());
   unsigned conditionRank = rank;