From 345c7f4e6915237f27fe0e82b4d57d6a17b91269 Mon Sep 17 00:00:00 2001
From: Armin Luntzer <armin.luntzer@univie.ac.at>
Date: Thu, 24 May 2018 11:26:03 +0200
Subject: [PATCH] add __clzsi2()
---
arch/sparc/kernel/ttable.S | 5 +--
lib/Makefile | 1 +
lib/libc_bitops.c | 66 ++++++++++++++++++++++++++++++++++++++
3 files changed, 68 insertions(+), 4 deletions(-)
create mode 100644 lib/libc_bitops.c
diff --git a/arch/sparc/kernel/ttable.S b/arch/sparc/kernel/ttable.S
index 8e9dcd4..c77453f 100644
--- a/arch/sparc/kernel/ttable.S
+++ b/arch/sparc/kernel/ttable.S
@@ -149,10 +149,9 @@ fpe_trap_handler:
hw_div0_trap_handler:
.global __interrupt_entry
__interrupt_entry:
- .global __clzsi2
-__clzsi2:
.global memset
memset:
+ ta 1
.global nmi_entry
nmi_entry:
.global reg_access_trap_handler
@@ -165,8 +164,6 @@ strtol:
syscall_tbl:
.global syscall_trap
syscall_trap:
- .global tag_overflow_trap_handler
-tag_overflow_trap_handler:
.global .udiv
.udiv:
.global .umul
diff --git a/lib/Makefile b/lib/Makefile
index 317fd22..ecd6def 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -9,3 +9,4 @@ lib-y += elf.o
lib-y += data_proc_tracker.o
lib-y += data_proc_task.o
lib-y += data_proc_net.o
+lib-y += libc_bitops.o
diff --git a/lib/libc_bitops.c b/lib/libc_bitops.c
new file mode 100644
index 0000000..b84b9fa
--- /dev/null
+++ b/lib/libc_bitops.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0
+/**
+ * @file lib/libc_bitops.c
+ *
+ * @ingroup libc
+ * @defgroup functions expected by the compiler
+ *
+ * @note these can be overridden by linking architecture-specific implementation
+ *
+ * @note add as needed
+ *
+ * @see https://gcc.gnu.org/onlinedocs/gccint/Integer-library-routines.html
+ *
+ */
+
+
+#include <kernel/export.h>
+
+
+/**
+ * @brief locates the most significant bit set in a word
+ * @note taken from linux: include/asm-generic/bitops/fls.h
+ */
+
+static int fls(int x)
+{
+ int r = 32;
+
+ if (!x)
+ return 0;
+ if (!(x & 0xffff0000u)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xff000000u)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xf0000000u)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xc0000000u)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x80000000u)) {
+ x <<= 1;
+ r -= 1;
+ }
+ return r;
+}
+
+
+/**
+ * @brief returns the number of leading 0-bits in a,
+ * starting at the most significant bit position.
+ * If a is zero, the result is undefined.
+ */
+
+int __attribute__((weak)) __clzsi2(unsigned int a);
+int __attribute__((weak)) __clzsi2(unsigned int a)
+{
+ return 32 - fls(a);
+}
+EXPORT_SYMBOL(__clzsi2);
--
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