On 2016-Sep-10, at 10:18 AM, Dimitry Andric <dim at FreeBSD.org> wrote:
> On 06 Sep 2016, at 15:04, Mark Millard <markmi at dsl-only.net> wrote: >> >> llvm's bugzilla reports that the stack-handling SVR4 ABI violation for >> TARGET_ARCH=powerpc has been fixed r280705 (likely on trunk)! > > I merged the upstream fix to projects/clang390-import: > > https://svnweb.freebsd.org/changeset/base/305686 > > -Dimitry Looking at things for this again I've submitted a question to https://llvm.org/bugs/show_bug.cgi?id=26519 asking if the post-amble code's side if things was also adjusted (instead of just the pre-amble/"claim" code side of things). [I'm not clang/llvm literate so I may have missed interpreted something when I looked.] My original submittal also noted the stack pointer adjustment-timing problem existed on the post-amble side in 3.8.0's code generation (when removing the frame from the stack): > 0x1801b8c <Buf_AddBytes+104>: lwz r30,24(r31) > 0x1801b90 <Buf_AddBytes+108>: lwz r29,20(r31) > 0x1801b94 <Buf_AddBytes+112>: lwz r28,16(r31) > 0x1801b98 <Buf_AddBytes+116>: lwz r27,12(r31) > 0x1801b9c <Buf_AddBytes+120>: lwz r26,8(r31) > 0x1801ba0 <Buf_AddBytes+124>: addi r1,r1,32 # Stack pointer adjusted > first > 0x1801ba4 <Buf_AddBytes+128>: lwz r0,4(r1) > 0x1801ba8 <Buf_AddBytes+132>: lwz r31,-4(r1) # Then Frame Pointer load > happens > # "outside" the new stack > range. > 0x1801bac <Buf_AddBytes+136>: mtlr r0 > 0x1801bb0 <Buf_AddBytes+140>: blr If such code can still be generated there would still be a time frame needing a red-zone to protect stack the contents from signals. Hopefully I'm just wrong and this was fixed too. === Mark Millard markmi at dsl-only.net _______________________________________________ freebsd-toolchain@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-toolchain To unsubscribe, send any mail to "freebsd-toolchain-unsubscr...@freebsd.org"
