diff options
Diffstat (limited to 'gcc/rtl.c')
| -rw-r--r-- | gcc/rtl.c | 36 |
1 files changed, 33 insertions, 3 deletions
diff --git a/gcc/rtl.c b/gcc/rtl.c index b10abd83fb5..a5d287ea455 100644 --- a/gcc/rtl.c +++ b/gcc/rtl.c @@ -150,6 +150,9 @@ struct obstack *rtl_obstack = &function_obstack; static unsigned int obstack_nesting_level; static void *function_ob_first_obj; +/* obstack.[ch] explicitly declined to prototype this. */ +extern int _obstack_allocated_p (struct obstack *h, void *obj); + /* Prepares for allocation of RTXes. */ void init_rtl (void) @@ -323,6 +326,21 @@ shared_const_p (const_rtx orig) && CONST_INT_P(XEXP (XEXP (orig, 0), 1))); } +/* Return TRUE if PTR points to function RTL memory. */ +static bool +allocated_in_function_mem_p(void * ptr) +{ + return _obstack_allocated_p (&function_obstack, ptr); +} + +/* If original is in the function memory and the current allocation mode + is permanent memory, do a copy, share otherwise. */ +static bool +need_copy_p(rtx orig) +{ + return allocated_in_function_mem_p (orig) + && rtl_obstack == &permanent_obstack; +} /* Create a new copy of an rtx. Recursively copies the operands of the rtx, @@ -346,21 +364,33 @@ copy_rtx (rtx orig) case CONST_INT: case CONST_DOUBLE: case CONST_FIXED: + case CONST_VECTOR: case SYMBOL_REF: case CODE_LABEL: case PC: case CC0: case SCRATCH: + if (!need_copy_p (orig)) + return orig; + /* TODO gc-improv: this and other RTX where it really does not make sense + to copy. */ /* SCRATCH must be shared because they represent distinct values. */ - return orig; + gcc_assert(code != SCRATCH); + break; case CLOBBER: - if (REG_P (XEXP (orig, 0)) && REGNO (XEXP (orig, 0)) < FIRST_PSEUDO_REGISTER) + if (!need_copy_p (orig) + && REG_P (XEXP (orig, 0)) + && REGNO (XEXP (orig, 0)) < FIRST_PSEUDO_REGISTER) return orig; break; case CONST: if (shared_const_p (orig)) - return orig; + { + /* Shared constants must be allocated in the permanent memory. */ + gcc_assert (!need_copy_p (orig)); + return orig; + } break; /* A MEM with a constant address is not sharable. The problem is that |