From b3b5ad95e64d1d5ce7070924123d8727b9a86ba5 Mon Sep 17 00:00:00 2001 From: Jeffrey A Law Date: Wed, 27 Oct 1999 06:18:11 +0000 Subject: [PATCH] alias.c: Update comments for ADDRESS. * alias.c: Update comments for ADDRESS. (nonlocal_reference_p): Look inside the ADDRESS to determine if it is a local memory reference. From-SVN: r30210 --- gcc/ChangeLog | 4 ++++ gcc/alias.c | 31 +++++++++++++++++++++++-------- 2 files changed, 27 insertions(+), 8 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index cf97fbf3cfb..fa17678030e 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -4,6 +4,10 @@ Tue Oct 26 23:15:03 1999 Mark Mitchell Tue Oct 26 23:29:18 1999 Jeffrey A Law (law@cygnus.com) + * alias.c: Update comments for ADDRESS. + (nonlocal_reference_p): Look inside the ADDRESS to determine if + it is a local memory reference. + * c-typeck.c (build_function_call): Check that the built-in function is of class BUILT_IN_NORMAL before trying to recongize it as BUILT_IN_ABS. diff --git a/gcc/alias.c b/gcc/alias.c index cc50c1b537f..59578d7b875 100644 --- a/gcc/alias.c +++ b/gcc/alias.c @@ -121,12 +121,16 @@ static int nonlocal_reference_p PROTO((rtx)); A base address can be an ADDRESS, SYMBOL_REF, or LABEL_REF. ADDRESS expressions represent certain special values: function arguments and - the stack, frame, and argument pointers. The contents of an address - expression are not used (but they are descriptive for debugging); - only the address and mode matter. Pointer equality, not rtx_equal_p, - determines whether two ADDRESS expressions refer to the same base - address. The mode determines whether it is a function argument or - other special value. */ + the stack, frame, and argument pointers. + + The contents of an ADDRESS is not normally used, the mode of the + ADDRESS determines whether the ADDRESS is a function argument or some + other special value. Pointer equality, not rtx_equal_p, determines whether + two ADDRESS expressions refer to the same base address. + + The only use of the contents of an ADDRESS is for determining if the + current function performs nonlocal memory memory references for the + purposes of marking the function as a constant function. */ static rtx *reg_base_value; static rtx *new_reg_base_value; @@ -1422,8 +1426,19 @@ nonlocal_reference_p (x) base = find_base_term (XEXP (x, 0)); if (base) { - /* Stack references are local. */ - if (GET_CODE (base) == ADDRESS && GET_MODE (base) == Pmode) + /* A Pmode ADDRESS could be a reference via the structure value + address or static chain. Such memory references are nonlocal. + + Thus, we have to examine the contents of the ADDRESS to find + out if this is a local reference or not. */ + if (GET_CODE (base) == ADDRESS + && GET_MODE (base) == Pmode + && (XEXP (base, 0) == stack_pointer_rtx + || XEXP (base, 0) == arg_pointer_rtx +#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM + || XEXP (base, 0) == hard_frame_pointer_rtx +#endif + || XEXP (base, 0) == frame_pointer_rtx)) return 0; /* Constants in the function's constant pool are constant. */ if (GET_CODE (base) == SYMBOL_REF && CONSTANT_POOL_ADDRESS_P (base)) -- 2.30.2