Hello all, I am experiencing problems with the following piece of code: lp_R0 = g_tcb[g_running_task].r0_ptr ; // restoring next task settings __asm { MOV R15, lp_R0 MOV R0, [R15] POP R15 POP R14 . . All the compiler's optimizations are enabled (common tail merging, register coloring, reorder instructions for pipline, alias checking, but not use static memory for non register automatics). the first line does not generate assembly (= I'm dead after the first MOV :-) ) even after declaring lp_R0 as 'volatile'. is there a way to disable optimizations locally? or maybe the only resort is to write the assembly for the line that the compiler won't generate?
R0 is the user stack pointer, and by changing the user stack pointer, you will have no access to any stack based variables anymore. Maybe this is the problem that you have. In-line assembly can be very tricky, since it is easy to mess-up the way the compiler works. So you should carefully read the guidelines in the user's guide. See http://www.keil.com/support/man/docs/c166/c166_le_extreguse.htm
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