[CherryPick][Intrinsic] lower_bound and upper_bound for binary search…

… in Sparse TIR. (apache#483) (#4)

* upd

* upd

* fix

* upd

* upd

* upd

* upd

* upd

* fix

* upd

* upd

* upd

* upd

* upd

* upd

* upd

* codegen-rule

* upd

* upd

* test

* upd

* fix

* two arguments

Co-authored-by: Zihao Ye <expye@outlook.com>

include/tvm/tir/builtin.h

@@ -494,6 +494,16 @@ TVM_DLL const Op& tvm_warp_shuffle_up();
 TVM_DLL const Op& tvm_warp_shuffle_down();
 TVM_DLL const Op& tvm_warp_activemask();
 
+/*!
+ * \brief Lower bound function for binary search.
+ */
+TVM_DLL const Op& tvm_lower_bound();
+
+/*!
+ * \brief Upper bound function for binary search.
+ */
+TVM_DLL const Op& tvm_upper_bound();
+
 /*!
  * \brief Initialize the global barrier.
  *  Call this at beginning of kernel that need global barrier.

python/tvm/script/tir/intrin.py

@@ -111,6 +111,16 @@ def max_value(dtype, span):
     return tvm.tir.max_value(dtype, span)
 
 
+@register
+def lower_bound(arr, val, l, r, span):
+    return tvm.tir.lower_bound(arr, val, l, r, span)
+
+
+@register
+def upper_bound(arr, val, l, r, span):
+    return tvm.tir.upper_bound(arr, val, l, r, span)
+
+
 @register
 def floordiv(x, y, span):
     return tvm.tir.floordiv(x, y, span)

python/tvm/tir/__init__.py

@@ -36,7 +36,7 @@
 from .function import PrimFunc
 
 from .op import call_packed, call_intrin, call_pure_extern, call_extern
-from .op import call_llvm_intrin, call_llvm_pure_intrin, ret, all, any, min_value, max_value, trace
+from .op import call_llvm_intrin, call_llvm_pure_intrin, ret, all, any, min_value, max_value, trace, lower_bound, upper_bound
 from .op import exp, exp2, exp10, log, log2, log10, log1p, ldexp, clz
 from .op import sin, sinh, asin, asinh
 from .op import cos, cosh, acos, acosh

python/tvm/tir/op.py

@@ -971,6 +971,62 @@ def ldexp(x1, x2):
     return call_intrin(x1.dtype, "tir.ldexp", x1, x2)  # type: ignore
 
 
+def lower_bound(arr, val, l, r, span=None):
+    """Return the position to the first element in the arr[l:r] that is no less than val.
+
+    Parameters
+    ----------
+    arr : Var
+        Pointer to the 1D buffer to apply binary search on.
+
+    val : PrimExpr
+        Value of the lower bound to search for in the buffer.
+
+    l : PrimExpr
+        Start position to search for in the buffer.
+    
+    r : PrimExpr
+        End position to search for in the buffer.
+
+    span : Optional[Span]
+        The location of this expression in the source code.
+
+    Returns
+    -------
+    PrimExpr
+        The index of element in arr[l:r] that is no less then given value.
+    """
+    return _ffi_api.lower_bound(arr, val, l, r, span)  # type: ignore
+
+
+def upper_bound(arr, val, l, r, span=None):
+    """Return the position the first element in the arr that is greater than val.
+
+    Parameters
+    ----------
+    arr : Var
+        Pointer to the 1D buffer to apply binary search on.
+
+    val : PrimExpr
+        Value of the upper bound to search for in the buffer.
+
+    l : PrimExpr
+        Start position to search for in the buffer.
+    
+    r : PrimExpr
+        End position to search for in the buffer.
+
+    span : Optional[Span]
+        The location of this expression in the source code.
+
+    Returns
+    -------
+    PrimExpr
+        The index of element in arr[l:r] that is no less then given value.
+    """
+    return _ffi_api.upper_bound(arr, val, l, r, span)  # type: ignore
+
+
 def isnan(x, span=None):
     """Check if input value is Nan.
 

src/target/source/codegen_cuda.cc

@@ -33,6 +33,7 @@
 #include <vector>
 
 #include "literal/cuda_half_t.h"
+#include "literal/cuda_binary_search.h"
 
 namespace tvm {
 namespace codegen {
@@ -132,6 +133,10 @@ std::string CodeGenCUDA::Finish() {
     decl_stream << "#include <mma.h>\n";
   }
 
+  if (need_binary_search_) {
+    decl_stream << _cuda_binary_search_def;
+  }
+
   decl_stream << "\n#ifdef _WIN32\n";
   decl_stream << "  using uint = unsigned int;\n";
   decl_stream << "  using uchar = unsigned char;\n";
@@ -723,6 +728,30 @@ void CodeGenCUDA::VisitExpr_(const CallNode* op, std::ostream& os) {
       this->PrintExpr(op->args[i * 2 + 1], os);
       os << "]" << ((i < 3) ? ", " : ")");
     }
+  } else if (op->op.same_as(builtin::tvm_lower_bound())) {
+    need_binary_search_ = true;
+    os << "__lower_bound(";
+    ICHECK_EQ(op->args.size(), 4U);
+    this->PrintExpr(op->args[0], os);
+    os << ", ";
+    this->PrintExpr(op->args[1], os);
+    os << ", ";
+    this->PrintExpr(op->args[2], os);
+    os << ", ";
+    this->PrintExpr(op->args[3], os);
+    os << ")";
+  } else if (op->op.same_as(builtin::tvm_upper_bound())) {
+    need_binary_search_ = true;
+    os << "__upper_bound(";
+    ICHECK_EQ(op->args.size(), 4U);
+    this->PrintExpr(op->args[0], os);
+    os << ", ";
+    this->PrintExpr(op->args[1], os);
+    os << ", ";
+    this->PrintExpr(op->args[2], os);
+    os << ", ";
+    this->PrintExpr(op->args[3], os);
+    os << ")";
   } else {
     CodeGenC::VisitExpr_(op, os);
   }

src/target/source/codegen_cuda.h

@@ -99,6 +99,8 @@ class CodeGenCUDA final : public CodeGenC {
   bool need_math_constants_h_{false};
   // whether need mma.h
   bool need_mma_h_{false};
+  // whether need binary search
+  bool need_binary_search_{false};
   // Op attribute map
   OpAttrMap<bool> op_need_warp_shuffle_ = Op::GetAttrMap<bool>("cuda.need_warp_shuffle");
 

src/target/source/literal/cuda_binary_search.h

@@ -0,0 +1,69 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+/*!
+ * \file cuda_binary_search.h
+ * \brief Binary search function definition for cuda codegen.
+ */
+#ifndef TVM_TARGET_SOURCE_LITERAL_CUDA_BINARY_SEARCH_H_
+#define TVM_TARGET_SOURCE_LITERAL_CUDA_BINARY_SEARCH_H_
+
+static constexpr const char* _cuda_binary_search_def = R"(
+template <typename DType>
+__forceinline__ __device__ int32_t __lower_bound(
+    const DType* __restrict__ arr,
+    DType val,
+    int32_t l,
+    int32_t r) {
+  int32_t low = l - 1, high = r;
+  /* loop invariant: low < mid < high, arr[low] < val, arr[high] >= val */
+  while (low + 1 < high) {
+    int32_t mid = (low + high) >> 1;
+    if (arr[mid] < val) {
+      low = mid;
+    } else {
+      high = mid;
+    }
+  }
+  // high = low + 1, arr[low] < val, arr[high] >= val
+  return high;
+}
+
+template <typename DType>
+__forceinline__ __device__ int32_t __upper_bound(
+    const DType* __restrict__ arr,
+    DType val,
+    int32_t l,
+    int32_t r) {
+  int32_t low = l - 1, high = r;
+  /* loop invariant: low < mid < high, arr[low] < val, arr[high] > val */
+  while (low + 1 < high) {
+    int32_t mid = (low + high) >> 1;
+    if (arr[mid] > val) {
+      high = mid;
+    } else {
+      low = mid;
+    }
+  }
+  // high = low + 1, arr[low] <= val, arr[high] > val
+  return high;
+}
+)";
+
+#endif  // TVM_TARGET_SOURCE_LITERAL_CUDA_BINARY_SEARCH_H_

src/tir/op/builtin.cc

@@ -222,6 +222,12 @@ TIR_DEFINE_BUILTIN_FUNC(tvm_thread_allreduce)
 TIR_DEFINE_BUILTIN_FUNC(tvm_load_matrix_sync)
     .set_attr<TCallEffectKind>("TCallEffectKind", Integer(CallEffectKind::kReadState));
 
+TIR_DEFINE_BUILTIN_FUNC(tvm_lower_bound)
+    .set_attr<TCallEffectKind>("TCallEffectKind", Integer(CallEffectKind::kOpaque));
+
+TIR_DEFINE_BUILTIN_FUNC(tvm_upper_bound)
+    .set_attr<TCallEffectKind>("TCallEffectKind", Integer(CallEffectKind::kOpaque));
+
 TIR_DEFINE_BUILTIN_FUNC(tvm_mma_sync)
     .set_attr<TCallEffectKind>("TCallEffectKind", Integer(CallEffectKind::kOpaque));
 

src/tir/op/op.cc

@@ -804,6 +804,16 @@ PrimExpr nearbyint(PrimExpr x, Span span) {
 
 TIR_REGISTER_PURE_UNARY_OP("tir.nearbyint");
 
+// lower_bound
+PrimExpr lower_bound(Var arr, PrimExpr val, PrimExpr l, PrimExpr r, Span span) {
+  return tir::Call({kDLInt, 32, 1}, builtin::tvm_lower_bound(), {arr, val, l, r}, span);
+}
+
+// upper_bound
+PrimExpr upper_bound(Var arr, PrimExpr val, PrimExpr l, PrimExpr r, Span span) {
+  return tir::Call({kDLInt, 32, 1}, builtin::tvm_upper_bound(), {arr, val, l, r}, span);
+}
+
 // trunc
 PrimExpr trunc(PrimExpr x, Span span) {
   if (x.dtype().is_int() || x.dtype().is_uint()) {
@@ -918,6 +928,10 @@ TVM_REGISTER_GLOBAL("tir.trunc").set_body_typed(tvm::trunc);
 
 TVM_REGISTER_GLOBAL("tir._cast").set_body_typed(tvm::cast);
 
+TVM_REGISTER_GLOBAL("tir.lower_bound").set_body_typed(tvm::lower_bound);
+
+TVM_REGISTER_GLOBAL("tir.upper_bound").set_body_typed(tvm::upper_bound);
+
 // operator overloading, smarter than make
 #define REGISTER_MAKE_BINARY_OP(Node, Func)                                                \
   TVM_REGISTER_GLOBAL("tir." #Node).set_body_typed([](PrimExpr a, PrimExpr b, Span span) { \

tests/python/unittest/test_tir_intrin.py

@@ -253,6 +253,55 @@ def test_fma():
     assert mod["test_tir_fma"].body.body.value.op.name == "tir.call_llvm_pure_intrin"
 
 
+@tvm.script.tir
+def binary_search(a: ty.handle, b: ty.handle, c: ty.handle, d: ty.handle) -> None:
+    n = tir.var('int32')
+    m = tir.var('int32')
+    A = tir.match_buffer(a, (n,), dtype='int32')
+    B = tir.match_buffer(b, (m,), dtype='int32')
+    C = tir.match_buffer(c, (m,), dtype='int32')
+    D = tir.match_buffer(d, (m,), dtype='int32')
+    with tir.block([m], 'search') as [vi]:
+        tir.reads([A[0:n], B[vi]])
+        tir.writes([C[vi], D[vi]])
+        C[vi] = tir.lower_bound(A.data, B[vi], 0, n)
+        D[vi] = tir.upper_bound(A.data, B[vi], 0, n)
+
+
+def test_binary_search():
+    sch = tir.Schedule(binary_search)
+    b = sch.get_block('search')
+    i, = sch.get_loops(b)
+    io, ii = sch.split(i, [1, None])
+    sch.bind(io, 'threadIdx.x')
+    sch.bind(ii, 'blockIdx.x')
+    f = tvm.build(sch.mod['main'], target='cuda')
+    # print(f.imported_modules[0].get_source())
+
+    x = np.arange(-128, 128).astype(np.int32)
+    y = np.random.randint(-200, 200, size=1024).astype(np.int32) 
+    a = np.zeros((1024,)).astype(np.int32)
+    b = np.zeros((1024,)).astype(np.int32)
+
+    # numpy results
+    np_a = np.searchsorted(x, y, side='left').astype(np.int32)
+    np_b = np.searchsorted(x, y, side='right').astype(np.int32)
+
+    # tvm results
+    dev = tvm.cuda(0)
+    x_array = tvm.nd.array(x, device=dev)
+    y_array = tvm.nd.array(y, device=dev)
+    a_array = tvm.nd.array(a, device=dev) 
+    b_array = tvm.nd.array(b, device=dev)
+    f(x_array, y_array, a_array, b_array)
+    tvm_a = a_array.numpy()
+    tvm_b = b_array.numpy()
+
+    # verify result
+    tvm.testing.assert_allclose(np_a, tvm_a)
+    tvm.testing.assert_allclose(np_b, tvm_b)
+
+
 if __name__ == "__main__":
     test_nearbyint()
     test_unary_intrin()
@@ -261,3 +310,4 @@ def test_fma():
     test_ldexp()
     test_clz()
     test_fma()
+    test_binary_search()