From cc4244d55f98b03603cf54eb4abac7e128e3c99a Mon Sep 17 00:00:00 2001
From: Frederik Gossen <frgossen@google.com>
Date: Wed, 20 Jan 2021 18:52:55 +0100
Subject: [PATCH] [MLIR][Standard] Add log1p operation to std

Differential Revision: https://reviews.llvm.org/D95041
---
 .../mlir/Dialect/StandardOps/IR/Ops.td        | 29 +++++++++++++++++++
 mlir/test/IR/core-ops.mlir                    |  3 ++
 2 files changed, 32 insertions(+)

diff --git a/mlir/include/mlir/Dialect/StandardOps/IR/Ops.td b/mlir/include/mlir/Dialect/StandardOps/IR/Ops.td
index 8db6129dbb88..770e68f6da83 100644
--- a/mlir/include/mlir/Dialect/StandardOps/IR/Ops.td
+++ b/mlir/include/mlir/Dialect/StandardOps/IR/Ops.td
@@ -1942,10 +1942,39 @@ def LogOp : FloatUnaryOp<"log"> {
   let summary = "base-e logarithm of the specified value";
 }
 
+//===----------------------------------------------------------------------===//
+// Log10Op
+//===----------------------------------------------------------------------===//
+
 def Log10Op : FloatUnaryOp<"log10"> {
   let summary = "base-10 logarithm of the specified value";
 }
 
+//===----------------------------------------------------------------------===//
+// Log1pOp
+//===----------------------------------------------------------------------===//
+
+def Log1pOp : FloatUnaryOp<"log1p"> {
+  let summary = "Computes the natural logarithm of one plus the given value";
+
+  let description = [{
+    Computes the base-e logarithm of one plus the given value. It takes one
+    operand and returns one result of the same type.
+
+    log1p(x) := log(1 + x)
+
+    Example:
+
+    ```mlir
+    %y = log1p %x : f64
+    ```
+  }];
+}
+
+//===----------------------------------------------------------------------===//
+// Log2Op
+//===----------------------------------------------------------------------===//
+
 def Log2Op : FloatUnaryOp<"log2"> {
   let summary = "base-2 logarithm of the specified value";
 }
diff --git a/mlir/test/IR/core-ops.mlir b/mlir/test/IR/core-ops.mlir
index 0e86050870ff..b5266fb2e580 100644
--- a/mlir/test/IR/core-ops.mlir
+++ b/mlir/test/IR/core-ops.mlir
@@ -596,6 +596,9 @@ func @standard_instrs(tensor<4x4x?xf32>, f32, i32, index, i64, f16) {
   // CHECK: %{{[0-9]+}} = ceildivi_signed %cst_4, %cst_4 : tensor<42xi32>
   %174 = ceildivi_signed %tci32, %tci32 : tensor<42 x i32>
 
+  // CHECK: %{{[0-9]+}} = log1p %arg1 : f32
+  %175 = log1p %f : f32
+
   return
 }