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| author | Uros Bizjak <ubizjak@gmail.com> | 2017-08-10 22:59:10 +0200 |
|---|---|---|
| committer | Uros Bizjak <uros@gcc.gnu.org> | 2017-08-10 22:59:10 +0200 |
| commit | e1769bdd4cef522ada32aec863feba41116b183a (patch) | |
| tree | bfa44ea06ab428cb984cd7189bf283a48a7726bf /gcc/config | |
| parent | f18f68226c2abb77008da7bd0aef5d7ee905c4c6 (diff) | |
| download | gcc-e1769bdd4cef522ada32aec863feba41116b183a.zip gcc-e1769bdd4cef522ada32aec863feba41116b183a.tar.gz gcc-e1769bdd4cef522ada32aec863feba41116b183a.tar.bz2 | |
re PR target/81708 (The x86 stack canary location should be customizable)
PR target/81708
* config/i386/i386.opt (mstack-protector-guard-symbol=): New option
* config/i386/i386.c (ix86_stack_protect_guard): Use
ix86_stack_protect_guard_symbol_str to generate varible declaration.
* doc/invoke.texi (x86 Options): Document
-mstack-protector-guard-symbol= option.
testsuite/ChangeLog:
PR target/81708
* gcc.target/i386/stack-prot-sym.c: New test.
From-SVN: r251040
Diffstat (limited to 'gcc/config')
| -rw-r--r-- | gcc/config/i386/i386.c | 48 | ||||
| -rw-r--r-- | gcc/config/i386/i386.opt | 4 |
2 files changed, 45 insertions, 7 deletions
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 9d59c78..1135372 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -45854,21 +45854,55 @@ ix86_mangle_type (const_tree type) } } +static GTY(()) tree ix86_tls_stack_chk_guard_decl; + static tree ix86_stack_protect_guard (void) { if (TARGET_SSP_TLS_GUARD) { tree type_node = lang_hooks.types.type_for_mode (ptr_mode, 1); - int qual = ENCODE_QUAL_ADDR_SPACE (ix86_stack_protector_guard_reg); - tree type = build_qualified_type (type_node, qual); - tree asptrtype = build_pointer_type (type); - tree sspoff = build_int_cst (asptrtype, - ix86_stack_protector_guard_offset); - tree t = build2 (MEM_REF, asptrtype, sspoff, - build_int_cst (asptrtype, 0)); + tree t; + + if (global_options_set.x_ix86_stack_protector_guard_symbol_str) + { + t = ix86_tls_stack_chk_guard_decl; + + if (t == NULL) + { + rtx x; + + t = build_decl + (UNKNOWN_LOCATION, VAR_DECL, + get_identifier (ix86_stack_protector_guard_symbol_str), + type); + TREE_STATIC (t) = 1; + TREE_PUBLIC (t) = 1; + DECL_EXTERNAL (t) = 1; + TREE_USED (t) = 1; + TREE_THIS_VOLATILE (t) = 1; + DECL_ARTIFICIAL (t) = 1; + DECL_IGNORED_P (t) = 1; + + /* Do not share RTL as the declaration is visible outside of + current function. */ + x = DECL_RTL (t); + RTX_FLAG (x, used) = 1; + + ix86_tls_stack_chk_guard_decl = t; + } + } + else + { + tree asptrtype = build_pointer_type (type); + + t = build_int_cst (asptrtype, ix86_stack_protector_guard_offset); + t = build2 (MEM_REF, asptrtype, t, + build_int_cst (asptrtype, 0)); + } + return t; } diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt index 72f2422..cd56431 100644 --- a/gcc/config/i386/i386.opt +++ b/gcc/config/i386/i386.opt @@ -938,6 +938,10 @@ Use the given offset for addressing the stack-protector guard. TargetVariable HOST_WIDE_INT ix86_stack_protector_guard_offset = 0 +mstack-protector-guard-symbol= +Target RejectNegative Joined Integer Var(ix86_stack_protector_guard_symbol_str) +Use the given symbol for addressing the stack-protector guard. + mmitigate-rop Target Var(flag_mitigate_rop) Init(0) Attempt to avoid generating instruction sequences containing ret bytes. |