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| author | Jim Wilson <wilson@gcc.gnu.org> | 1993-02-05 15:33:36 -0800 |
|---|---|---|
| committer | Jim Wilson <wilson@gcc.gnu.org> | 1993-02-05 15:33:36 -0800 |
| commit | 0b298be41774d1999726d9e4f3a5547403ca41c9 (patch) | |
| tree | a87bef4d23830355e56938af12b8159a00ad7bd7 /gcc/sched.c | |
| parent | 0a56ad627e91edd29d348813c4fd15c57e1c930a (diff) | |
| download | gcc-0b298be41774d1999726d9e4f3a5547403ca41c9.zip gcc-0b298be41774d1999726d9e4f3a5547403ca41c9.tar.gz gcc-0b298be41774d1999726d9e4f3a5547403ca41c9.tar.bz2 | |
(true_dependence, anti_dependence, output_dependence):
Assume that MEM_IN_STRUCT_P QImode varying addresses can overlap a
non-MEM_IN_STRUCT_P fixed address.
From-SVN: r3426
Diffstat (limited to 'gcc/sched.c')
| -rw-r--r-- | gcc/sched.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/gcc/sched.c b/gcc/sched.c index 5483fc8..386d66e 100644 --- a/gcc/sched.c +++ b/gcc/sched.c @@ -696,8 +696,11 @@ memrefs_conflict_p (xsize, x, ysize, y, c) changed. A volatile and non-volatile reference can be interchanged though. - A MEM_IN_STRUCT reference at a varying address can never conflict with a - non-MEM_IN_STRUCT reference at a fixed address. */ + A MEM_IN_STRUCT reference at a non-QImode varying address can never + conflict with a non-MEM_IN_STRUCT reference at a fixed address. We must + allow QImode aliasing because the ANSI C standard allows character + pointers to alias anything. We are assuming that characters are + always QImode here. */ /* Read dependence: X is read after read in MEM takes place. There can only be a dependence here if both reads are volatile. */ @@ -731,8 +734,10 @@ true_dependence (mem, x) || (memrefs_conflict_p (SIZE_FOR_MODE (mem), XEXP (mem, 0), SIZE_FOR_MODE (x), XEXP (x, 0), 0) && ! (MEM_IN_STRUCT_P (mem) && rtx_addr_varies_p (mem) + && GET_MODE (mem) != QImode && ! MEM_IN_STRUCT_P (x) && ! rtx_addr_varies_p (x)) && ! (MEM_IN_STRUCT_P (x) && rtx_addr_varies_p (x) + && GET_MODE (x) != QImode && ! MEM_IN_STRUCT_P (mem) && ! rtx_addr_varies_p (mem)))); } @@ -753,8 +758,10 @@ anti_dependence (mem, x) || (memrefs_conflict_p (SIZE_FOR_MODE (mem), XEXP (mem, 0), SIZE_FOR_MODE (x), XEXP (x, 0), 0) && ! (MEM_IN_STRUCT_P (mem) && rtx_addr_varies_p (mem) + && GET_MODE (mem) != QImode && ! MEM_IN_STRUCT_P (x) && ! rtx_addr_varies_p (x)) && ! (MEM_IN_STRUCT_P (x) && rtx_addr_varies_p (x) + && GET_MODE (x) != QImode && ! MEM_IN_STRUCT_P (mem) && ! rtx_addr_varies_p (mem)))); } @@ -769,8 +776,10 @@ output_dependence (mem, x) || (memrefs_conflict_p (SIZE_FOR_MODE (mem), XEXP (mem, 0), SIZE_FOR_MODE (x), XEXP (x, 0), 0) && ! (MEM_IN_STRUCT_P (mem) && rtx_addr_varies_p (mem) + && GET_MODE (mem) != QImode && ! MEM_IN_STRUCT_P (x) && ! rtx_addr_varies_p (x)) && ! (MEM_IN_STRUCT_P (x) && rtx_addr_varies_p (x) + && GET_MODE (x) != QImode && ! MEM_IN_STRUCT_P (mem) && ! rtx_addr_varies_p (mem)))); } |