libs/log2ceil: Move implementation of log2ceil to a common place

Move log2ceil from riscv_pmp to libc. Also, implement log2floor for
completeness.

These are the run-time alternative to the compile-time macros.
This commit is contained in:
Ville Juven 2023-12-13 13:28:05 +02:00 committed by Xiang Xiao
parent 90d73153fb
commit e03599d9ae
6 changed files with 151 additions and 26 deletions

View File

@ -32,6 +32,7 @@
#include <nuttx/compiler.h>
#include <nuttx/arch.h>
#include <nuttx/irq.h>
#include <nuttx/lib/math32.h>
#include "riscv_internal.h"
@ -88,32 +89,6 @@ typedef struct pmp_entry_s pmp_entry_t;
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: log2ceil
*
* Description:
* Calculate the up-rounded power-of-two for input.
*
* Input Parameters:
* x - Argument to calculate the power-of-two from.
*
* Returned Value:
* Power-of-two for argument, rounded up.
*
****************************************************************************/
static uintptr_t log2ceil(uintptr_t x)
{
uintptr_t pot = 0;
for (x = x - 1; x; x >>= 1)
{
pot++;
}
return pot;
}
/****************************************************************************
* Name: pmp_check_region_attrs
*

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@ -249,6 +249,38 @@ void umul64(FAR const struct uint64_s *factor1,
FAR const struct uint64_s *factor2,
FAR struct uint64_s *product);
/****************************************************************************
* Name: log2ceil
*
* Description:
* Calculate the up-rounded power-of-two for input.
*
* Input Parameters:
* x - Argument to calculate the power-of-two from.
*
* Returned Value:
* Power-of-two for argument, rounded up.
*
****************************************************************************/
uintptr_t log2ceil(uintptr_t x);
/****************************************************************************
* Name: log2floor
*
* Description:
* Calculate the down-rounded (truncated) power-of-two for input.
*
* Input Parameters:
* x - Argument to calculate the power-of-two from.
*
* Returned Value:
* Power-of-two for argument, rounded (truncated) down.
*
****************************************************************************/
uintptr_t log2floor(uintptr_t x);
#undef EXTERN
#ifdef __cplusplus
}

View File

@ -82,6 +82,10 @@ list(
lib_err.c
lib_instrument.c)
# Add generic integer math functions
list(APPEND SRCS lib_log2ceil.c lib_log2floor.c)
# Keyboard driver encoder/decoder
if(CONFIG_LIBC_KBDCODEC)

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@ -42,6 +42,10 @@ CSRCS += lib_crc64.c lib_crc32.c lib_crc16.c lib_crc16ccitt.c lib_crc8.c
CSRCS += lib_crc8ccitt.c lib_crc8table.c lib_glob.c lib_execinfo.c
CSRCS += lib_ftok.c lib_err.c lib_instrument.c
# Add generic integer math functions
CSRCS += lib_log2ceil.c lib_log2floor.c
# Keyboard driver encoder/decoder
ifeq ($(CONFIG_LIBC_KBDCODEC),y)

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@ -0,0 +1,55 @@
/****************************************************************************
* libs/libc/misc/lib_log2ceil.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/lib/math32.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: log2ceil
*
* Description:
* Calculate the up-rounded power-of-two for input.
*
* Input Parameters:
* x - Argument to calculate the power-of-two from.
*
* Returned Value:
* Power-of-two for argument, rounded up.
*
****************************************************************************/
uintptr_t log2ceil(uintptr_t x)
{
uintptr_t pot = 0;
for (x = x - 1; x; x >>= 1)
{
pot++;
}
return pot;
}

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@ -0,0 +1,55 @@
/****************************************************************************
* libs/libc/misc/lib_log2floor.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/lib/math32.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: log2floor
*
* Description:
* Calculate the down-rounded (truncated) power-of-two for input.
*
* Input Parameters:
* x - Argument to calculate the power-of-two from.
*
* Returned Value:
* Power-of-two for argument, rounded (truncated) down.
*
****************************************************************************/
uintptr_t log2floor(uintptr_t x)
{
uintptr_t pot = 0;
for (; x > 1; x >>= 1)
{
pot++;
}
return pot;
}