Interprocedural optimization plus some minor fixes:

– fixed handling LDX/LDY/LDZ when inlining variables into registers
– fixed CLA/CLX/CLY instruction generation
– refactored optimization definitions

docs/abi/variable-storage.md

@@ -53,7 +53,7 @@ and ending when the function returns.
 Most automatic variables reside in memory. 
 They can share their memory location with other automatic variables and parameters, 
 to conserve memory usage. 
-Some small automatic variables may be inlined to index registers. 
+Some small automatic variables may be inlined to registers. 
 They are not automatically initialized before reading, reading them before initialization yields an undefined value. 
 Automatic local variables are not safe to use with reentrant functions, see the [relevant documentation](../lang/reentrancy.md) for more details.
 
@@ -66,7 +66,7 @@ of the function call to the function they're defined in
 and ending when the function returns. 
 They reside in memory and can share their memory location with other parameters and automatic variables, 
 to conserve memory usage. 
-Unlike automatic variables, they are never inlined into index registers.
+Unlike automatic variables, they are almost never inlined into registers.
 Parameters are not safe to use with reentrant functions, see the [relevant documentation](../lang/reentrancy.md) for more details.
 
 

docs/api/command-line.md

@@ -89,13 +89,19 @@ This may cause problems if the parameter table is stored next to a hardware regi
 
 * `--inline` – Inline functions automatically (experimental). See the [documentation about inlining](../abi/inlining.md). Computationally easy, can give decent gains.
 
+* `--fipo`, `--fno-ipo` – Whether should perform interprocedural optimization.
+It enables certain optimization similar to what inlining would enable, but without actual inlining.
+
 * `--size` – Optimize for size, sacrificing some speed (experimental).
 
 * `--fast` – Optimize for speed, even if it increases the size a bit (experimental).
 
 * `--blast-processing` – Optimize for speed, even if it increases the size a lot (experimental).
+Enables `--inline` automatically. 
 
-* `--dangerous-optimizations` – Use dangerous optimizations (experimental). Dangerous optimizations are more likely to result in broken code.
+* `--dangerous-optimizations` – Use dangerous optimizations (experimental).
+Dangerous optimizations are more likely to result in broken code.
+Enables `--fipo` automatically. 
 
 ## Warning options
 

docs/api/getting-started.md

@@ -45,6 +45,8 @@ You may be also interested in the following:
 
 * `--inline` – automatically inline functions for better optimization
 
+* `--fipo` – enable interprocedural optimization
+
 * `-s` – additionally generate assembly output
 
 * `-g` – additionally generate a label file, in format compatible with VICE emulator