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tccasm: Support refs to anon symbols from asm

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This happens when e.g. string constants (or other static data)
are passed as operands to inline asm as immediates.  The produced
symbol ref wouldn't be found.  So tighten the connection between
C and asm-local symbol table even more.
This commit is contained in:
Michael Matz
2016-08-26 18:11:19 +02:00
parent dd57a34866
commit 5bd8aeb917
4 changed files with 52 additions and 13 deletions
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23
tests/tcctest.c
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@ -2741,6 +2741,28 @@ void override_func2 (void)
void override_func2 (void)
{
printf ("asmc: override2\n");
}
/* This checks a construct used by the linux kernel to encode
references to strings by PC relative references. */
extern int bug_table[] __attribute__((section("__bug_table")));
char * get_asm_string (void)
{
extern int some_symbol;
asm volatile (".globl some_symbol\n"
"jmp .+6\n"
"1:\n"
"some_symbol: .long 0\n"
".pushsection __bug_table, \"a\"\n"
".globl bug_table\n"
"bug_table:\n"
/* The first entry (1b-2b) is unused in this test,
but we include it to check if cross-section
PC-relative references work. */
"2:\t.long 1b - 2b, %c0 - 2b\n"
".popsection\n" : : "i" ("A string"));
char * str = ((char*)bug_table) + bug_table[1];
return str;
}
unsigned int set;
@ -2812,6 +2834,7 @@ void asm_test(void)
8 bit. */
asm volatile("cmp %1,%2; sete %0" : "=a"(somebool) : "r"(1), "r"(2));
if (!somebool)
printf("asmbool: failed\n");
#endif
printf("asmstr: %s\n", get_asm_string());
return;