From: H.J. Lu Date: Thu, 19 Jul 2018 10:47:23 +0000 (+0000) Subject: i386: Change indirect_return to function type attribute X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=39a6a24334f95e047dcd7e0b27c2f27f6340bdc6;p=gcc.git i386: Change indirect_return to function type attribute In struct ucontext; typedef struct ucontext ucontext_t; extern int (*bar) (ucontext_t *__restrict __oucp, const ucontext_t *__restrict __ucp) __attribute__((__indirect_return__)); extern int res; void foo (ucontext_t *oucp, ucontext_t *ucp) { res = bar (oucp, ucp); } bar() may return via indirect branch. This patch changes indirect_return to type attribute to allow indirect_return attribute on variable or type of function pointer so that ENDBR can be inserted after call to bar(). gcc/ PR target/86560 * config/i386/i386.c (rest_of_insert_endbranch): Lookup indirect_return as function type attribute. (ix86_attribute_table): Change indirect_return to function type attribute. * doc/extend.texi: Update indirect_return attribute. gcc/testsuite/ PR target/86560 * gcc.target/i386/pr86560-1.c: New test. * gcc.target/i386/pr86560-2.c: Likewise. * gcc.target/i386/pr86560-3.c: Likewise. From-SVN: r262877 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index ecdaf32fd77..78b8d39ab2b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2018-07-19 H.J. Lu + + PR target/86560 + * config/i386/i386.c (rest_of_insert_endbranch): Lookup + indirect_return as function type attribute. + (ix86_attribute_table): Change indirect_return to function + type attribute. + * doc/extend.texi: Update indirect_return attribute. + 2018-07-19 Aldy Hernandez * wide-int.h (widest2_int): New. diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 2b7e9489ed8..ee409cfe7e4 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -2635,16 +2635,23 @@ rest_of_insert_endbranch (void) { rtx call = get_call_rtx_from (insn); rtx fnaddr = XEXP (call, 0); + tree fndecl = NULL_TREE; /* Also generate ENDBRANCH for non-tail call which may return via indirect branch. */ - if (MEM_P (fnaddr) - && GET_CODE (XEXP (fnaddr, 0)) == SYMBOL_REF) + if (GET_CODE (XEXP (fnaddr, 0)) == SYMBOL_REF) + fndecl = SYMBOL_REF_DECL (XEXP (fnaddr, 0)); + if (fndecl == NULL_TREE) + fndecl = MEM_EXPR (fnaddr); + if (fndecl + && TREE_CODE (TREE_TYPE (fndecl)) != FUNCTION_TYPE + && TREE_CODE (TREE_TYPE (fndecl)) != METHOD_TYPE) + fndecl = NULL_TREE; + if (fndecl && TYPE_ARG_TYPES (TREE_TYPE (fndecl))) { - tree fndecl = SYMBOL_REF_DECL (XEXP (fnaddr, 0)); - if (fndecl - && lookup_attribute ("indirect_return", - DECL_ATTRIBUTES (fndecl))) + tree fntype = TREE_TYPE (fndecl); + if (lookup_attribute ("indirect_return", + TYPE_ATTRIBUTES (fntype))) need_endbr = true; } } @@ -45920,8 +45927,8 @@ static const struct attribute_spec ix86_attribute_table[] = ix86_handle_fndecl_attribute, NULL }, { "function_return", 1, 1, true, false, false, false, ix86_handle_fndecl_attribute, NULL }, - { "indirect_return", 0, 0, true, false, false, false, - ix86_handle_fndecl_attribute, NULL }, + { "indirect_return", 0, 0, false, true, true, false, + NULL, NULL }, /* End element. */ { NULL, 0, 0, false, false, false, false, NULL, NULL } diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index abac85c5cb2..7b471ec40f7 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -5889,8 +5889,9 @@ foo (void) @item indirect_return @cindex @code{indirect_return} function attribute, x86 -The @code{indirect_return} attribute on a function is used to inform -the compiler that the function may return via indirect branch. +The @code{indirect_return} attribute can be applied to a function, +as well as variable or type of function pointer to inform the +compiler that the function may return via indirect branch. @end table diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index f78a7c82a89..8c60524cdee 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,10 @@ +2018-07-19 H.J. Lu + + PR target/86560 + * gcc.target/i386/pr86560-1.c: New test. + * gcc.target/i386/pr86560-2.c: Likewise. + * gcc.target/i386/pr86560-3.c: Likewise. + 2018-07-19 Kyrylo Tkachov * gfortran.dg/max_fmax_aarch64.f90: New test. diff --git a/gcc/testsuite/gcc.target/i386/pr86560-1.c b/gcc/testsuite/gcc.target/i386/pr86560-1.c new file mode 100644 index 00000000000..a2b702695c5 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr86560-1.c @@ -0,0 +1,16 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fcf-protection" } */ +/* { dg-final { scan-assembler-times {\mendbr} 2 } } */ + +struct ucontext; + +extern int (*bar) (struct ucontext *) + __attribute__((__indirect_return__)); + +extern int res; + +void +foo (struct ucontext *oucp) +{ + res = bar (oucp); +} diff --git a/gcc/testsuite/gcc.target/i386/pr86560-2.c b/gcc/testsuite/gcc.target/i386/pr86560-2.c new file mode 100644 index 00000000000..6f01b385afd --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr86560-2.c @@ -0,0 +1,16 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fcf-protection" } */ +/* { dg-final { scan-assembler-times {\mendbr} 2 } } */ + +struct ucontext; + +typedef int (*bar_p) (struct ucontext *) + __attribute__((__indirect_return__)); + +extern int res; + +void +foo (bar_p bar, struct ucontext *oucp) +{ + res = bar (oucp); +} diff --git a/gcc/testsuite/gcc.target/i386/pr86560-3.c b/gcc/testsuite/gcc.target/i386/pr86560-3.c new file mode 100644 index 00000000000..05328e24509 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr86560-3.c @@ -0,0 +1,17 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fcf-protection" } */ +/* { dg-final { scan-assembler-times {\mendbr} 2 } } */ + +struct ucontext; + +extern int (*bar) (struct ucontext *); + +extern int res; + +void +foo (struct ucontext *oucp) +{ + int (*f) (struct ucontext *) __attribute__((__indirect_return__)) + = bar; + res = f (oucp); +}