RFA: another patch to fix PR61360
Tue Sep 23 01:26:00 GMT 2014
The previous patch to solve PR61360 fixed the problem in IRA (it was
easier for me to do as I know the code well)
Although imo it was an ok fix, Richard expressed concerns with the
patch and the practice to have different enable attribute values
depending on the current pass.
I don't understand why "x,m" alternative is better to "x,r" and "x,r"
should be disabled. Even if the path from general regs to sse regs is
slow (usually such slow path is implemented internally by
micro-architecture through cache). "x,r" alternative results in only
smaller insns (including number of insns) with probably the same time
for the movement. So "x,r" should be at least no slower, insn cache
should have more locality, and less overhead for decoding/translating insns.
Here I propose another solution avoiding to have different enable
The patch was successfully bootstrapped on x86/x86-64 and tested with
and without -march=amdfam10 (actually the patch results in 2 less
failures when -march=amdfam10 were used).
Uros, is i386.md change ok for the trunk?
2014-09-22 Vladimir Makarov <email@example.com>
* lra.c (lra): Remove call of recog_init.
* config/i386/i386.md (*float<SWI48:mode><MODEF:mode>2_sse):
Always enable first alternative.
-------------- next part --------------
--- config/i386/i386.md (revision 215337)
+++ config/i386/i386.md (working copy)
@@ -4795,14 +4795,6 @@
&& X87_ENABLE_FLOAT (<MODEF:MODE>mode,
- (eq_attr "alternative" "1")
- /* ??? For sched1 we need constrain_operands to be able to
- select an alternative. Leave this enabled before RA. */
- (symbol_ref "TARGET_INTER_UNIT_CONVERSIONS
- || optimize_function_for_size_p (cfun)
- || !(reload_completed
- || reload_in_progress
- || lra_in_progress)")
--- lra.c (revision 215358)
+++ lra.c (working copy)
@@ -2135,11 +2135,6 @@ lra (FILE *f)
lra_in_progress = 1;
- /* The enable attributes can change their values as LRA starts
- although it is a bad practice. To prevent reuse of the outdated
- values, clear them. */
- recog_init ();
lra_live_range_iter = lra_coalesce_iter = 0;
lra_constraint_iter = lra_constraint_iter_after_spill = 0;
lra_inheritance_iter = lra_undo_inheritance_iter = 0;
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