tree a7662189c032076e7e0e29460168043e3ce6d572
parent fdf0af774aabb31ba8a62f358b7b40dfe8b35da9
author Cherry Zhang <cherryyz@google.com> 1561064750 -0400
committer Ian Lance Taylor <iant@golang.org> 1561156725 +0000

compiler: intrinsify some math/bits functions

Let the Go frontend recognize some math/bits functions and turn
them into intrinsics.

Corresponding change in the GCC backend:

Index: gcc/go/go-gcc.cc
===================================================================
--- gcc/go/go-gcc.cc	(revision 272290)
+++ gcc/go/go-gcc.cc	(working copy)
@@ -613,7 +613,7 @@
 						NULL_TREE),
 		       false, false);

-  // Used by runtime/internal/sys.
+  // Used by runtime/internal/sys and math/bits.
   this->define_builtin(BUILT_IN_CTZ, "__builtin_ctz", "ctz",
 		       build_function_type_list(integer_type_node,
 						unsigned_type_node,
@@ -624,6 +624,31 @@
 						long_long_unsigned_type_node,
 						NULL_TREE),
 		       true, false);
+  this->define_builtin(BUILT_IN_CLZ, "__builtin_clz", "clz",
+		       build_function_type_list(integer_type_node,
+						unsigned_type_node,
+						NULL_TREE),
+		       true, false);
+  this->define_builtin(BUILT_IN_CLZLL, "__builtin_clzll", "clzll",
+		       build_function_type_list(integer_type_node,
+						long_long_unsigned_type_node,
+						NULL_TREE),
+		       true, false);
+  this->define_builtin(BUILT_IN_POPCOUNT, "__builtin_popcount", "popcount",
+		       build_function_type_list(integer_type_node,
+						unsigned_type_node,
+						NULL_TREE),
+		       true, false);
+  this->define_builtin(BUILT_IN_POPCOUNTLL, "__builtin_popcountll", "popcountll",
+		       build_function_type_list(integer_type_node,
+						long_long_unsigned_type_node,
+						NULL_TREE),
+		       true, false);
+  this->define_builtin(BUILT_IN_BSWAP16, "__builtin_bswap16", "bswap16",
+		       build_function_type_list(uint16_type_node,
+						uint16_type_node,
+						NULL_TREE),
+		       true, false);
   this->define_builtin(BUILT_IN_BSWAP32, "__builtin_bswap32", "bswap32",
 		       build_function_type_list(uint32_type_node,
 						uint32_type_node,

Change-Id: If44b18882c885f1c93d4682890f176b89cbc5b1a
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/183266
Reviewed-by: Ian Lance Taylor <iant@golang.org>