Add new command to implement `setFrame:` override on a UIView at runtime. about happydebugging HOT 5 OPEN

Some testing suggests that you can't add a symbolic breakpoint in this way.

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One alternative is to breakpoint in the parent, check the type of class of the current instance in the condition of the breakpoint, and then print the frame using memory read --format f --size 8 --count 4 $rsp.

Alternatives I tried were: executing __asm__("int3") inside of the class_addMethod implementation. But that won't work since its assembly.

I also tried adding a symbolic breakpoint to a dummy method using the following, and it failed to resolve it:

e (BOOL)class_addMethod([MyView class], @selector(setFrame:), (IMP)imp_implementationWithBlock(^(id self, CGRect frame) { (void)NSLog(@"test"); }), "v@{CGRect={CGPoint=dd}{CGSize=dd}}")

break set -F '-[MyView setFrame:]' -L objc

Note: I couldn't seem to get the implementation to work by casting a function, so I used imp_implementationWithBlock(). Perhaps it could be done if the actual function exists? But it seems unlikely. The problem seems to be the symbol isn't there for the symbolic breakpoint even though we add an implementation at runtime.

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The biggest downside would be handling all of the different calling conventions. Above was working with x86_64.

Using this website, I was using: https://www.raywenderlich.com/615-assembly-register-calling-convention-tutorial

First Argument: RDI
Second Argument: RSI
Third Argument: RDX
Fourth Argument: RCX
Fifth Argument: R8
Sixth Argument: R9

Meaning $rdi would be self and (SEL)$rsi would be _cmd.

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Another useful reference for calling conventions: https://github.com/stephanemoore/archives/blob/master/general/calling-conventions.md

arm64: https://developer.apple.com/library/archive/documentation/Xcode/Conceptual/iPhoneOSABIReference/Articles/ARM64FunctionCallingConventions.html

arm6: https://developer.apple.com/library/archive/documentation/Xcode/Conceptual/iPhoneOSABIReference/Articles/ARMv7FunctionCallingConventions.html#//apple_ref/doc/uid/TP40009022-SW1

i386: https://wiki.osdev.org/Calling_Conventions#Cheat_Sheets

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Architecture can be inferred from GetSelectedTarget or target list.

64-bit simulator = x86_64
32-bit simulator = i386
64-bit device = arm64
32-bit device = arm7

https://docs.elementscompiler.com/Platforms/Cocoa/CpuArchitectures/

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