On 21 June 2012 09:48, Tristan Gingold wrote: > Here is the new version. It is now possible to use __builtin_frame_address > (0) to get the current establisher frame thanks to a tiny adjustment. > > No regressions on x86_64-linux, and an x86_64-windows native gdb can be built > and run. > > Tristan. > [...] > diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h > index ddb3645..44533e0 100644 > --- a/gcc/config/i386/i386.h > +++ b/gcc/config/i386/i386.h > @@ -729,6 +729,18 @@ enum target_cpu_default > /* Boundary (in *bits*) on which the incoming stack is aligned. */ > #define INCOMING_STACK_BOUNDARY ix86_incoming_stack_boundary > > +/* According to Windows x64 software convention, the maximum stack > allocatable > + in the prologue is 4G - 8 bytes. Furthermore, there is a limited set of > + instructions allowed to adjust the stack pointer in the epilog, forcing > the > + use of frame pointer for frames larger than 2 GB. This theorical limit > + is reduced by 256, an over-estimated upper bound for the stack use by the > + prologue. > + We define only one threshold for both the prolog and the epilog. When the > + frame size is larger than this threshold, we allocate the are to save SSE A typo there? s/the are/the area/
> + regs, then save them, and then allocate the remaining. There is no SEH > + unwind info for this later allocation. */ > +#define SEH_MAX_FRAME_SIZE ((2U << 30) - 256) > [...] -- VZ
