On 09/22/2017 10:59 AM, Peter Maydell wrote: > ARM v8M specifies that the INVPC usage fault for mismatched > xPSR exception field and handler mode bit should be checked > before updating the PSR and SP, so that the fault is taken > with the existing stack frame rather than by pushing a new one. > Perform this check in the right place for v8M. > > Since v7M specifies in its pseudocode that this usage fault > check should happen later, we have to retain the original > code for that check rather than being able to merge the two. > (The distinction is architecturally visible but only in > very obscure corner cases like attempting an invalid exception > return with an exception frame in read only memory.) > > Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> > --- > target/arm/helper.c | 30 +++++++++++++++++++++++++++--- > 1 file changed, 27 insertions(+), 3 deletions(-)
Reviewed-by: Richard Henderson <richard.hender...@linaro.org> r~
