From b759ea284782b95cf0196c8e813e3ab7e1233c47 Mon Sep 17 00:00:00 2001 From: Alexandre Oliva Date: Fri, 9 Nov 2018 10:15:46 +0000 Subject: [PATCH] [PR87793] reject non-toplevel unspecs in debug loc exprs on x86 Before revision 254025, we'd reject UNSPECs in debug loc exprs. TARGET_CONST_NOT_OK_FOR_DEBUG_P still rejects that by default, on all ports that override it, except for x86, that accepts @gotoff unspecs. We can indeed accept them in top-level expressions, but not as subexpressions: the assembler rejects the difference between two @gotoff symbols, for example. We could simplify such a difference and drop the @gotoffs, provided that the symbols are in the same section; we could also accept @gotoffs plus literal constants. However, accepting those but rejecting such combinations as subexpressions would be ugly, and most likely not worth the trouble: sym@gotoff+litconst hardly makes sense as a standalone expression, and the difference between @gotoffs should be avoided to begin with, as follows. Ideally, the debug loc exprs would use the symbolic data in REG_EQUIV/REG_EQUAL notes, or delegitimized addresses, instead of simplifying the difference between two legitimized addresses so that the occurrences of the GOT register cancel each other. That would require some more elaborate surgery in var-tracking and cselib than would be appropriate at this stage. for gcc/ChangeLog PR target/87793 * config/i386/i386.c (ix86_const_not_ok_for_debug_p): Reject non-toplevel UNSPEC. for gcc/testsuite/ChangeLog PR target/87793 * gcc.dg/pr87793.c: New. From-SVN: r265956 --- gcc/ChangeLog | 6 ++++++ gcc/config/i386/i386.c | 12 ++++++++++++ gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gcc.dg/pr87793.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 65 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/pr87793.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 9df874d..21d9ae7 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2018-11-09 Alexandre Oliva + + PR target/87793 + * config/i386/i386.c (ix86_const_not_ok_for_debug_p): Reject + non-toplevel UNSPEC. + 2018-11-08 Aldy Hernandez * tree-vrp.c (value_range::check): Do not access internals diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 77dec0f..711bec0 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -17177,6 +17177,18 @@ ix86_const_not_ok_for_debug_p (rtx x) if (SYMBOL_REF_P (x) && strcmp (XSTR (x, 0), GOT_SYMBOL_NAME) == 0) return true; + /* Reject UNSPECs within expressions. We could accept symbol@gotoff + + literal_constant, but that would hardly come up in practice, + and it's not worth the trouble of having to reject that as an + operand to pretty much anything else. */ + if (UNARY_P (x) + && GET_CODE (XEXP (x, 0)) == UNSPEC) + return true; + if (BINARY_P (x) + && (GET_CODE (XEXP (x, 0)) == UNSPEC + || GET_CODE (XEXP (x, 1)) == UNSPEC)) + return true; + return false; } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index aa79847..9a7dfc2 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-11-09 Alexandre Oliva + + PR target/87793 + * gcc.dg/pr87793.c: New. + 2018-11-09 Prathamesh Kulkarni * gcc.target/arm/neon-vect-div-1.c: New test. diff --git a/gcc/testsuite/gcc.dg/pr87793.c b/gcc/testsuite/gcc.dg/pr87793.c new file mode 100644 index 0000000..3194313 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr87793.c @@ -0,0 +1,42 @@ +/* { dg-do compile } */ +/* { dg-options "-fpic -Os -g" } */ + +struct fit_loadable_tbl { + int type; + void (*handler)(int data, int size); +}; + +#define ll_entry_start(_type, _list) \ +({ \ + static char start[0] __attribute__((aligned(4))) \ + __attribute__((unused, section(".u_boot_list_2_"#_list"_1"))); \ + (_type *)&start; \ +}) + +#define ll_entry_end(_type, _list) \ +({ \ + static char end[0] __attribute__((aligned(4))) \ + __attribute__((unused, section(".u_boot_list_2_"#_list"_3"))); \ + (_type *)&end; \ +}) + +#define ll_entry_count(_type, _list) \ + ({ \ + _type *start = ll_entry_start(_type, _list); \ + _type *end = ll_entry_end(_type, _list); \ + unsigned int _ll_result = end - start; \ + _ll_result; \ + }) + +void test(int img_type, int img_data, int img_len) +{ + int i; + const unsigned int count = + ll_entry_count(struct fit_loadable_tbl, fit_loadable); + struct fit_loadable_tbl *fit_loadable_handler = + ll_entry_start(struct fit_loadable_tbl, fit_loadable); + + for (i = 0; i < count; i++, fit_loadable_handler++) + if (fit_loadable_handler->type == img_type) + fit_loadable_handler->handler(img_data, img_len); +} -- 2.7.4