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--- dev:crosscompiler:backend_arm:exceptions [2019/11/15 16:29] – [ARM Exceptions] ursgraf
+++ dev:crosscompiler:backend_arm:exceptions [2019/11/17 18:24] (current) – [Floats in Exceptions] ursgraf
@@ Line 17: / Line 17: @@
 ===== Floats in Exceptions =====
+In order to save processing time, floating point registers are not saved when entering exception handling. If an exception method calls a another method which uses EXTRs, however, all volatile EXTR's will be saved by a call to //US.ENABLE_FLOATS()//. Nonvolatile EXTR's, which are used in a method, will be saved on the stack by the prolog of a method in any case. //US.ENABLE_FLOATS()// has to be called in a exception method or in a method which is called by an exception method.\\
+**Important:** A decrementer exception calls an action method. The decrementer class could be extended and its action method could be overridden. If this method of the subclass uses floats, you have to insert //US.ENABLE_FLOATS()// as well.
+**Important:** If an exception method or a method called by an exception method uses a method from //java/lang/Math//, you have to make sure that //US.FLOAT_ENABLE()// is called.

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