Re: [Qemu-discuss] QEMU: DBT vs. Interpretation

2015-01-28 Thread Javier Picorel
Yes, your assumption is right. Every time we execute the same binary and settings (w/o I/O), we get the same instruction trace. The question is whether DBT introduces any source of indeterminism (e.g., arbitrary reordering of instructions in the TB or something that does not violate correctnes

Re: [Qemu-discuss] QEMU: DBT vs. Interpretation

2015-01-28 Thread Peter Maydell
On 28 January 2015 at 02:51, Dale R. Worley wrote: > Javier Picorel writes: >> We are trying to make QEMU deterministic for >> architectural simulation. In the absence of I/O, >> let's say only user code or exceptions, is there >> any source of indeterminism (e.g., non deterministic >> compiler o

Re: [Qemu-discuss] QEMU: DBT vs. Interpretation

2015-01-27 Thread Dale R. Worley
Javier Picorel writes: > We are trying to make QEMU deterministic for > architectural simulation. In the absence of I/O, > let's say only user code or exceptions, is there > any source of indeterminism (e.g., non deterministic > compiler optimizations, TB indeterminism) of > QEMU's DBT versus

Re: [Qemu-discuss] QEMU: DBT vs. Interpretation

2015-01-26 Thread Peter Maydell
On 26 January 2015 at 17:26, Javier Picorel wrote: > Dear all, > > We are trying to make QEMU deterministic for > architectural simulation. In the absence of I/O, > let’s say only user code or exceptions, is there > any source of indeterminism (e.g., non deterministic > compiler optimizations, TB

[Qemu-discuss] QEMU: DBT vs. Interpretation

2015-01-26 Thread Javier Picorel
Dear all, We are trying to make QEMU deterministic for architectural simulation. In the absence of I/O, let’s say only user code or exceptions, is there any source of indeterminism (e.g., non deterministic compiler optimizations, TB indeterminism) of QEMU’s DBT versus a canonical interpreter?