implement ffs

Author: c8ef

libc/config/linux/aarch64/entrypoints.txt

@@ -93,6 +93,9 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.strings.bcmp
     libc.src.strings.bcopy
     libc.src.strings.bzero
+    libc.src.strings.ffs
+    libc.src.strings.ffsl
+    libc.src.strings.ffsll
     libc.src.strings.index
     libc.src.strings.rindex
     libc.src.strings.strcasecmp

libc/config/linux/x86_64/entrypoints.txt

@@ -93,6 +93,9 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.strings.bcmp
     libc.src.strings.bcopy
     libc.src.strings.bzero
+    libc.src.strings.ffs
+    libc.src.strings.ffsl
+    libc.src.strings.ffsll
     libc.src.strings.index
     libc.src.strings.rindex
     libc.src.strings.strcasecmp

libc/include/strings.yaml

@@ -29,6 +29,24 @@ functions:
     arguments:
       - type: void *
       - type: size_t
+  - name: ffs
+    standards: 
+    - POSIX
+    return_type: int
+    arguments:
+      - int
+  - name: ffsl
+    standards: 
+    - POSIX
+    return_type: int
+    arguments:
+      - long
+  - name: ffsll
+    standards: 
+    - POSIX
+    return_type: int
+    arguments:
+      - long long
   - name: index
     standards:
       - BSDExtensions

libc/src/strings/CMakeLists.txt

@@ -54,6 +54,30 @@ add_entrypoint_object(
     bcopy.h
 )
 
+add_entrypoint_object(
+  ffs
+  SRCS
+    ffs.cpp
+  HDRS
+    ffs.h
+)
+
+add_entrypoint_object(
+  ffsl
+  SRCS
+    ffsl.cpp
+  HDRS
+    ffsl.h
+)
+
+add_entrypoint_object(
+  ffsll
+  SRCS
+    ffsll.cpp
+  HDRS
+    ffsll.h
+)
+
 add_entrypoint_object(
   index
   SRCS

libc/src/strings/ffs.cpp

@@ -0,0 +1,17 @@
+//===-- Implementation of ffs ---------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/strings/ffs.h"
+#include "src/__support/common.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(int, ffs, (int i)) { return __builtin_ffs(i); }
+
+} // namespace LIBC_NAMESPACE_DECL

libc/src/strings/ffs.h

@@ -0,0 +1,20 @@
+//===-- Implementation header for ffs ---------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STRINGS_FFS_H
+#define LLVM_LIBC_SRC_STRINGS_FFS_H
+
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+int ffs(int i);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_STRINGS_FFS_H

libc/src/strings/ffsl.cpp

@@ -0,0 +1,17 @@
+//===-- Implementation of ffsl --------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/strings/ffsl.h"
+#include "src/__support/common.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(int, ffsl, (long i)) { return __builtin_ffsl(i); }
+
+} // namespace LIBC_NAMESPACE_DECL

libc/src/strings/ffsl.h

@@ -0,0 +1,20 @@
+//===-- Implementation header for ffsl --------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STRINGS_FFSL_H
+#define LLVM_LIBC_SRC_STRINGS_FFSL_H
+
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+int ffsl(long i);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_STRINGS_FFSL_H

libc/src/strings/ffsll.cpp

@@ -0,0 +1,17 @@
+//===-- Implementation of ffsll -------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/strings/ffsll.h"
+#include "src/__support/common.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(int, ffsll, (long long i)) { return __builtin_ffsll(i); }
+
+} // namespace LIBC_NAMESPACE_DECL

libc/src/strings/ffsll.h

@@ -0,0 +1,20 @@
+//===-- Implementation header for ffsll -------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STRINGS_FFSLL_H
+#define LLVM_LIBC_SRC_STRINGS_FFSLL_H
+
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+int ffsll(long long i);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_STRINGS_FFSLL_H