[llvm] ba9dc5f - [ADT] Add is_splat overload accepting initializer_list

[Jakub Kuderski via llvm-commits]

Author: Jakub Kuderski
Date: 2022-08-08T10:20:02-04:00
New Revision: ba9dc5f577389db2cc706c0c66615f430a55d153

URL: https://github.com/llvm/llvm-project/commit/ba9dc5f577389db2cc706c0c66615f430a55d153
DIFF: https://github.com/llvm/llvm-project/commit/ba9dc5f577389db2cc706c0c66615f430a55d153.diff

LOG: [ADT] Add is_splat overload accepting initializer_list

Allow for `is_splat` to be used inline, similar to `is_contained`, e.g.,
```
if (is_splat({type1, type2, type3, type4}))
  ...
```

which is much more concise and less typo-prone than an equivalent chain of equality comparisons.

My immediate motivation is to clean up some code in the SPIR-V dialect that currently needs to either construct a temporary container or use `makeArrayRef` before calling `is_splat`.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D131289

Added: 
    

Modified: 
    llvm/include/llvm/ADT/STLExtras.h
    llvm/unittests/ADT/STLExtrasTest.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/ADT/STLExtras.h b/llvm/include/llvm/ADT/STLExtras.h
index 0efa96e69a8ce..0aaefb5e0ee29 100644
--- a/llvm/include/llvm/ADT/STLExtras.h
+++ b/llvm/include/llvm/ADT/STLExtras.h
@@ -1796,6 +1796,11 @@ bool is_splat(R &&Range) {
          std::equal(adl_begin(Range) + 1, adl_end(Range), adl_begin(Range)));
 }
 
+/// Returns true iff all Values in the initializer lists are same.
+template <typename T> bool is_splat(std::initializer_list<T> Values) {
+  return is_splat<std::initializer_list<T>>(std::move(Values));
+}
+
 /// Provide a container algorithm similar to C++ Library Fundamentals v2's
 /// `erase_if` which is equivalent to:
 ///

diff  --git a/llvm/unittests/ADT/STLExtrasTest.cpp b/llvm/unittests/ADT/STLExtrasTest.cpp
index a32c823e73b66..f7281f8af0704 100644
--- a/llvm/unittests/ADT/STLExtrasTest.cpp
+++ b/llvm/unittests/ADT/STLExtrasTest.cpp
@@ -606,7 +606,7 @@ TEST(STLExtrasTest, EarlyIncrementTestCustomPointerIterator) {
   EXPECT_EQ(EIR.end(), I);
 }
 
-TEST(STLExtrasTest, splat) {
+TEST(STLExtrasTest, IsSplat) {
   std::vector<int> V;
   EXPECT_FALSE(is_splat(V));
 
@@ -621,6 +621,13 @@ TEST(STLExtrasTest, splat) {
   EXPECT_FALSE(is_splat(V));
 }
 
+TEST(STLExtrasTest, IsSplatInitializerList) {
+  EXPECT_TRUE(is_splat({1}));
+  EXPECT_TRUE(is_splat({1, 1}));
+  EXPECT_FALSE(is_splat({1, 2}));
+  EXPECT_TRUE(is_splat({1, 1, 1}));
+}
+
 TEST(STLExtrasTest, to_address) {
   int *V1 = new int;
   EXPECT_EQ(V1, to_address(V1));