basm

To better explain what I'm trying to accomplish, I'm going to start with something that works. Say we have a procedure that can call another procedure and pass a string parameter to it: procedure CallSaySomething(AProc: Pointer; const AValue: string); var LAddr: Integer; begin LAddr := Integer(PChar(AValue)); asm MOV EAX, LAddr CALL AProc; end; end; This is the procedure that we will call: procedure SaySomething(const AValue: string); begin ShowMessage( AValue ); end; Now I can call SaySomething like so(tested and works (: ): CallSaySomething(@SaySomething, 'Morning people!'); My question is,

I have some sample source code for OpenGL, I wanted to compile a 64bit version (using Delphi XE2) but there's some ASM code which fails to compile, and I know nothing about ASM. Here's the code below, and I put the two error messages on the lines which fail... // Copy a pixel from source to dest and Swap the RGB color values procedure CopySwapPixel(const Source, Destination: Pointer); asm push ebx //[DCC Error]: E2116 Invalid combination of opcode and operands mov bl,[eax+0] mov bh,[eax+1] mov [edx+2],bl mov [edx+1],bh mov bl,[eax+2] mov bh,[eax+3] mov [edx+0],bl mov [edx+3],bh pop ebx //[DCC

When writing a Delphi procedure or function in assembly code, which registers must be saved and restored to the original value at the end of the procedure? When calling another Delphi procedure or function from (inline) assembly code, what can I expect that other function to do with the registers? Which registers will be restored to their original values and which may not? (Obviously, the same answer would apply to both questions) I am assuming the default calling convention of Delphi. I know that EAX is used for 32-bit return values. And looking at the asm code in SysUtils.pas, it seems that

I have a little problem with FLD instruction in x64 bit ... want to load Double value to the stack pointer FPU in st0 register, but it seem to be impossible. In Delphi x32, I can use this code : function DoSomething(X:Double):Double; asm FLD X // Do Something .. FST Result end; Unfortunately, in x64, the same code does not work. In x64 mode floating point parameters are passed in xmm-registers. So when Delphi tries to compile FLD X, it becomes FLD xmm0 but there is no such instruction. You first need to move it to memory. The same goes with the result, it should be passed back in xmm0. Try