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--- dev:crosscompiler:backend_arm:code_generator [2019/11/17 18:19] – [Fixup] ursgraf
+++ dev:crosscompiler:backend_arm:code_generator [2019/11/17 19:53] – [Exception Stackframe] ursgraf
@@ Line 21: / Line 21: @@
 [{{ :dev:crosscompiler:backend_arm:exceptionstackframearm.png?350&direct | //Stack frame for exception method//}}]
+For efficiency, the exception stack frame does not contain space for locals. Hence, you are not allowed to use so many locals that this becomes necessary. This will be checked for when compiling exception methods.
 Optimization: The ARM architecture has lots of EXTR's. One could use half of them in normal methods and the other half in exception methods. For such a case all normal methods which could be called from within exception methods must be translated a second time with the second set. The compiler would have to find out how to handle each method.
@@ Line 36: / Line 37: @@
   * Addresses of class variables
   * Addresses of constants (floats, strings, type descriptors)
-Such addresses must be loaded with the aid of an auxiliary registers. After linking these addresses are known and must be corrected in the code. For this purpose a table called //fixups// is maintained. It contains all references to the objects, which were created by the class file reader and whose final addresses must be inserted into the code. In order to know at what position in the machine code array a certain correction has to be made, the next position is stored in the instruction //addi// as an immediate operand beginning with the last position (//lastFixup//).
+Such addresses must be loaded with the aid of an auxiliary registers. After linking these addresses are known and must be corrected in the code. For this purpose a table called //fixups// is maintained. It contains all references to the objects, which were created by the class file reader and whose final addresses must be inserted into the code. In order to know at what position in the machine code array a certain correction has to be made, the next position is stored in the instruction //movw// as an immediate operand beginning with the last position (//lastFixup//).
 ===== Accessing the Hardware =====

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