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comrade
January 26th, 2004, 14:20
movups xmm1,[mem]

its disassembled fine, but I cannot seem to find display of SSE register in OllyDbg. Only MMX/3DNow!/FPU

blabberer
January 28th, 2004, 04:32
you cant see xmm1 register comrade
have you tried this
debugging option (alt+o)----->registers----checkmark decode sse registers

xmm0 1.020219e+34, 1.743804e-39, 9.219563e-41, 1.742610e-39
xmm1 1.024959e+34, 1.743826e-39, -NAN FFFFFFFF, 1.010113e+34

hope this helps

comrade
January 28th, 2004, 21:15
thanks!

comrade
January 28th, 2004, 21:50
What about SSE2 registers?

blabberer
January 29th, 2004, 09:52
hey comrade ollys help file says it all
SSE (Streaming SIMD Extentions) instructions were first introduced by Intel for Pentium III processor. They allow for simultaneous processing of up to 4 single-precision floating-point operands. OllyDbg 1.06 disassembles and assembles SSE commands and can display and modify the contents of 128-bit SSE registers. This task is not as trivial as it looks at the first glance. The main problem is the lack of debugging support in all actual versions of Windows, that is, Debugger can't get these registers from the OS. To overcome this limitation, OllyDbg injects and executes small piece of code that reads or updates SSE registers within the debugged thread. This operation is slow and dangerous, and I recommend to disable decoding of SSE registers unless absolutely necessary. Run trace doesn't save SSE registers to the log.

Notice that SSE2 (Pentium 4 extentions) is not supported.