| Message ID | CAAs8HmwUsxkmbyYCKMhjw3xhJS7nyBhtTfBUiKF6swFG=bmcnA@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
ok (for google branch). David On Mon, Oct 20, 2014 at 1:44 PM, Sriraman Tallam <tmsriram@google.com> wrote: > On Mon, Oct 20, 2014 at 12:59 PM, Xinliang David Li <davidxl@google.com> wrote: >> On Mon, Oct 20, 2014 at 11:59 AM, Sriraman Tallam <tmsriram@google.com> wrote: >>> On Mon, Oct 20, 2014 at 10:51 AM, Andrew Pinski <pinskia@gmail.com> wrote: >>>> On Mon, Oct 20, 2014 at 10:46 AM, Sriraman Tallam <tmsriram@google.com> wrote: >>>>> On Mon, Oct 20, 2014 at 10:42 AM, Xinliang David Li <davidxl@google.com> wrote: >>>>>> Why removing the tree_code check? >>>>> >>>>> The actual problem happens because STRING_CSTs (end up in .lrodata) >>>>> are not set a far address as they dont match the VAR_DECL check here. >>>>> Futher, "ix86_in_large_data_p" call has the TREE_CODE check to do the >>>>> right thing so this seems unnecessary & buggy here. >>>> >>>> I think he is asking because TREE_STATIC (decl) || DECL_EXTERNAL >>>> (decl) might be an issue for STRING_CSTs. >>> >>> TREE_STATIC is true for STRING_CSTs and DECL_EXTERNAL false, that looks ok. >> >> The values for STRING_CST make sense, but it is not documented in >> tree.h for use with STRING_CST. Maybe do this: >> >> if (((TREE_CODE (decl) == VAR_DECL&& (TREE_STATIC (decl) || >> DECL_EXTERNAL (decl)) >> ||TREE_CODE (decl) == STRING_CST) >> && ix86_in_large_data_p (decl)) >> >> which can be simplified to: >> >> if ((TREE_CODE (decl) == VAR_DECL && is_global_var (decl) ||TREE_CODE >> (decl) == STRING_CST) >> && ix86_in_large_data_p (decl)) > > Patch updated. > > Thanks > Sri > >> ... >> >> David >>> >>> Thanks >>> Sri >>> >>>> >>>> Thanks, >>>> Andrew >>>> >>>> >>>>> >>>>> Thanks >>>>> Sri >>>>> >>>>>> >>>>>> David >>>>>> >>>>>> On Mon, Oct 20, 2014 at 10:35 AM, Sriraman Tallam <tmsriram@google.com> wrote: >>>>>>> Hi, >>>>>>> >>>>>>> This patch is under review for trunk GCC : >>>>>>> https://gcc.gnu.org/ml/gcc-patches/2014-10/msg01638.html. >>>>>>> >>>>>>> In the mean time, is this ok for google/gcc-4_9 branch? Without >>>>>>> this, -mcmodel=medium is unusable if .lrodata goes beyond the 2G >>>>>>> boundary. >>>>>>> >>>>>>> Thanks >>>>>>> Sri
Index: config/i386/i386.c =================================================================== --- config/i386/i386.c (revision 216287) +++ config/i386/i386.c (working copy) @@ -41331,8 +41331,8 @@ ix86_encode_section_info (tree decl, rtx rtl, int { default_encode_section_info (decl, rtl, first); - if (TREE_CODE (decl) == VAR_DECL - && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)) + if (((TREE_CODE (decl) == VAR_DECL && is_global_var (decl)) + || TREE_CODE(decl) == STRING_CST) && ix86_in_large_data_p (decl)) SYMBOL_REF_FLAGS (XEXP (rtl, 0)) |= SYMBOL_FLAG_FAR_ADDR; } Index: testsuite/gcc.dg/pr63538.c =================================================================== --- testsuite/gcc.dg/pr63538.c (revision 0) +++ testsuite/gcc.dg/pr63538.c (revision 0) @@ -0,0 +1,14 @@ +/* PR63538 is about not using 64-bit addresses for .lrodata accesses when it + involves STRING_CSTs. */ +/* { dg-do compile { target x86_64-*-* } } */ +/* { dg-options "-O2 -mcmodel=medium -mlarge-data-threshold=0" { target x86_64-*-* } } */ + +#include <stdio.h> + +const char *str = "Hello World"; + +int main() { + printf("str = %p %s\n",str, str); + return 0; +} +/* { dg-final { scan-assembler-not "movl" } } */