Sign Up
Log In
Log In
or
Sign Up
Places
All Projects
Status Monitor
Collapse sidebar
openSUSE:13.1
gcc43
ibm311554-ltoc-r164044:164046
Overview
Repositories
Revisions
Requests
Users
Attributes
Meta
File ibm311554-ltoc-r164044:164046 of Package gcc43
2010-09-09 Alan Modra <amodra@gmail.com> * doc/invoke.text: Reinstate mcmodel=medium. * config/rs6000/linux64.h (SUBSUBTARGET_OVERRIDE_OPTIONS): Set CMODEL_MEDIUM as default. * config/rs6000/rs6000.h (enum rs6000_cmodel): Add CMODEL_MEDIUM. * config/rs6000/rs6000.c (rs6000_handle_option): Add mcmodel=medium. (toc_relative_ok, offsettable_ok_by_alignment): New functions. (rs6000_emit_move): Reinstate mcmodel=medium optimization. Index: gcc/doc/invoke.texi =================================================================== --- gcc/doc/invoke.texi (revision 164044) +++ gcc/doc/invoke.texi (revision 164046) @@ -15213,6 +15213,11 @@ scheduling parameters set by @option{-mt Generate PowerPC64 code for the small model: The TOC is limited to 64k. +@item -mcmodel=medium +@opindex mcmodel=medium +Generate PowerPC64 code for the medium model: The TOC and other static +data may be up to a total of 4G in size. + @item -mcmodel=large @opindex mcmodel=large Generate PowerPC64 code for the large model: The TOC may be up to 4G Index: gcc/config/rs6000/linux64.h =================================================================== --- gcc/config/rs6000/linux64.h (revision 164044) +++ gcc/config/rs6000/linux64.h (revision 164046) @@ -134,7 +134,7 @@ extern enum rs6000_cmodel cmodel; else \ { \ if (!rs6000_explicit_options.cmodel) \ - SET_CMODEL (CMODEL_LARGE); \ + SET_CMODEL (CMODEL_MEDIUM); \ if (cmodel != CMODEL_SMALL) \ { \ TARGET_NO_FP_IN_TOC = 0; \ Index: gcc/config/rs6000/rs6000.c =================================================================== --- gcc/config/rs6000/rs6000.c (revision 164044) +++ gcc/config/rs6000/rs6000.c (revision 164046) @@ -4000,6 +4000,8 @@ rs6000_handle_option (size_t code, const case OPT_mcmodel_: if (strcmp (arg, "small") == 0) cmodel = CMODEL_SMALL; + else if (strcmp (arg, "medium") == 0) + cmodel = CMODEL_MEDIUM; else if (strcmp (arg, "large") == 0) cmodel = CMODEL_LARGE; else @@ -6992,6 +6994,80 @@ rs6000_eliminate_indexed_memrefs (rtx op copy_addr_to_reg (XEXP (operands[1], 0))); } +/* Return true if OP, a SYMBOL_REF, should be considered local when + generating -mcmodel=medium code. */ + +static bool +toc_relative_ok (rtx op) +{ + tree decl; + + if (!SYMBOL_REF_LOCAL_P (op)) + return false; + + /* This is a bit hard to explain. When building shared libraries, + you are supposed to pass -fpic or -fPIC to the compiler. + -fpic/-fPIC not only generate position independent code but also + generate code that supports ELF shared library global function + or variable overriding. ppc64 is always PIC and at least some of + the ELF shared libaray semantics of global variables happen to be + supported without -fpic/-fPIC. So people may not be careful + about using -fPIC for shared libs. + With -mcmodel=medium this situation changes. A shared library + built without -fpic/-fPIC requires text relocs for global var + access (and would fail to load since glibc ld.so doesn't support + the required dynamic relocs). So avoid this potential + problem by using -mcmodel=large access for global vars, unless + we know we are compiling for an executable. */ + if (flag_pie) + return true; + + decl = SYMBOL_REF_DECL (op); + if (!decl || !DECL_P (decl)) + return true; + if (!TREE_PUBLIC (decl)) + return true; + if (DECL_VISIBILITY (decl) != VISIBILITY_DEFAULT) + return true; + + /* If we get here we must have a global var. See binds_local_p. */ + return flag_whole_program; +} + +/* Return true if memory accesses to DECL are known to never straddle + a 32k boundary. */ + +static bool +offsettable_ok_by_alignment (tree decl) +{ + unsigned HOST_WIDE_INT dsize, dalign; + + /* Presume any compiler generated symbol_ref is suitably aligned. */ + if (!decl) + return true; + + if (TREE_CODE (decl) != VAR_DECL + && TREE_CODE (decl) != PARM_DECL + && TREE_CODE (decl) != RESULT_DECL + && TREE_CODE (decl) != FIELD_DECL) + return true; + + if (!DECL_SIZE_UNIT (decl)) + return false; + + if (!host_integerp (DECL_SIZE_UNIT (decl), 1)) + return false; + + dsize = tree_low_cst (DECL_SIZE_UNIT (decl), 1); + if (dsize <= 1) + return true; + if (dsize > 32768) + return false; + + dalign = DECL_ALIGN_UNIT (decl); + return dalign >= dsize; +} + /* Emit a move from SOURCE to DEST in mode MODE. */ void rs6000_emit_move (rtx dest, rtx source, enum machine_mode mode) @@ -7305,11 +7381,16 @@ rs6000_emit_move (rtx dest, rtx source, /* If this is a SYMBOL_REF that refers to a constant pool entry, and we have put it in the TOC, we just need to make a TOC-relative reference to it. */ - if (TARGET_TOC - && GET_CODE (operands[1]) == SYMBOL_REF - && constant_pool_expr_p (operands[1]) - && ASM_OUTPUT_SPECIAL_POOL_ENTRY_P (get_pool_constant (operands[1]), - get_pool_mode (operands[1]))) + if ((TARGET_TOC + && GET_CODE (operands[1]) == SYMBOL_REF + && constant_pool_expr_p (operands[1]) + && ASM_OUTPUT_SPECIAL_POOL_ENTRY_P (get_pool_constant (operands[1]), + get_pool_mode (operands[1]))) + || (TARGET_CMODEL == CMODEL_MEDIUM + && GET_CODE (operands[1]) == SYMBOL_REF + && !CONSTANT_POOL_ADDRESS_P (operands[1]) + && toc_relative_ok (operands[1]) + && offsettable_ok_by_alignment (SYMBOL_REF_DECL (operands[1])))) { rtx reg = NULL_RTX; if (TARGET_CMODEL != CMODEL_SMALL) Index: gcc/config/rs6000/rs6000.h =================================================================== --- gcc/config/rs6000/rs6000.h (revision 164044) +++ gcc/config/rs6000/rs6000.h (revision 164046) @@ -297,9 +297,11 @@ extern const char *host_detect_local_cpu /* Code model for 64-bit linux. small: 16-bit toc offsets. - large: 32-bit toc offsets. */ + medium: 32-bit toc offsets, static data and code within 2G of TOC pointer. + large: 32-bit toc offsets, no limit on static data and code. */ enum rs6000_cmodel { CMODEL_SMALL, + CMODEL_MEDIUM, CMODEL_LARGE };
Locations
Projects
Search
Status Monitor
Help
OpenBuildService.org
Documentation
API Documentation
Code of Conduct
Contact
Support
@OBShq
Terms
openSUSE Build Service is sponsored by
The Open Build Service is an
openSUSE project
.
Sign Up
Log In
Places
Places
All Projects
Status Monitor
