主循环和ISR中的浮点计算结果偶尔会被破坏

大家好，


在我的用于STM8S003的Cosmic C程序中我遇到了一个问题：某些浮点计算的结果偶尔会被破坏。
变量的使用不能成为原因，因为使用的变量是中断保存。变量和堆栈的RAM空间也不会变窄。还剩下很多空间。

在我的正常主循环程序中，有一些浮点计算（乘法，加法，除法）。
在中断服务程序中，还使用了浮点乘法和加法。
当我在主循环计算完成时禁用中断时，问题就消失了！但我真的不想那样做。我想了解原因。

在反汇编中，我注意到在两种情况下（main和ISR）都使用了以下程序集“'函数''：
CALL c_rtol
CALL c_ltor
CALL c_fmul

当从main和ISR调用相同的“函数”时，这些函数是否可能不可重入并且数据被破坏？

在这种情况下，这是正常还是可以被视为错误？

谢谢。



以下为原文




Hello everybody,


in my Cosmic C program for a STM8S003 I have a problem: The result of some floating point calculations are sporadically corrupted.
The usage of variables can not be the cause for that because the used ones are are interrupt-save. Also RAM space for variables and stack is not getting narrow. There is much space left.

In my normal main loop program there are some floating point calculations (multiplications, additions, divisions).
In an interrupt service routine there are also floating point multiplications and additions used.
When I disable interrupts while the main loop calculations are done the problem is gone! But I don't really want to do that. I want to understand the cause.

In the disassembly I noticed that in both cases (main and ISR) the folowing assembly ''functions'' are used:
CALL  c_rtol  
CALL  c_ltor  
CALL  c_fmul

Could it be possible that these functions are not reentrant and that data is corrupted when the same ''function'' is called from main and from the ISR?

When this is the case, is this normal or could it be considered as a bug?

Thank you.