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| author | bonzini <bonzini@138bc75d-0d04-0410-961f-82ee72b054a4> | 2006-04-03 11:20:07 +0000 |
|---|---|---|
| committer | bonzini <bonzini@138bc75d-0d04-0410-961f-82ee72b054a4> | 2006-04-03 11:20:07 +0000 |
| commit | 897f76b247c2985b4861f463a65403301884eaa5 (patch) | |
| tree | e8c7101e8fefacd29cfe88d998da545388f1d4d1 /gcc/regclass.c | |
| parent | 4e5032b1377a0543ed6b822a1cb647a76c758e89 (diff) | |
| download | gcc-897f76b247c2985b4861f463a65403301884eaa5.tar.gz | |
2005-08-08 Paolo Bonzini <bonzini@gnu.org>
Dale Johannesen <dalej@apple.com>
PR target/19653
* regclass.c (struct reg_pref): Update documentation.
(regclass): Set prefclass to NO_REGS if memory is the best option.
(record_reg_classes): Cope with a prefclass set to NO_REGS.
* reload.c (find_reloads): Take PREFERRED_OUTPUT_RELOAD_CLASS
into account. For non-registers, equate an empty preferred
reload class to a `!' in the constraint; move the if clause to
do so after those that reject the insn.
(push_reload): Allow PREFERRED_*_RELOAD_CLASS to liberally
return NO_REGS.
(find_dummy_reload): Likewise.
* doc/tm.texi (Register Classes): Document what it means
if PREFERRED_*_RELOAD_CLASS return NO_REGS.
* config/i386/i386.c (ix86_preferred_reload_class): Force
using SSE registers (and return NO_REGS for floating-point
constants) if math is done with SSE.
(ix86_preferred_output_reload_class): New.
* config/i386/i386-protos.h (ix86_preferred_output_reload_class): New.
* config/i386/i386.h (PREFERRED_OUTPUT_RELOAD_CLASS): New.
* config/i386/i386.md: Remove # register preferences.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@112637 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/regclass.c')
| -rw-r--r-- | gcc/regclass.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/gcc/regclass.c b/gcc/regclass.c index f76fdcd77cf..1f1e6c24166 100644 --- a/gcc/regclass.c +++ b/gcc/regclass.c @@ -811,7 +811,8 @@ struct costs /* Structure used to record preferences of given pseudo. */ struct reg_pref { - /* (enum reg_class) prefclass is the preferred class. */ + /* (enum reg_class) prefclass is the preferred class. May be + NO_REGS if no class is better than memory. */ char prefclass; /* altclass is a register class that we should use for allocating @@ -1314,6 +1315,10 @@ regclass (rtx f, int nregs) best = reg_class_subunion[(int) best][class]; } + /* If no register class is better than memory, use memory. */ + if (p->mem_cost < best_cost) + best = NO_REGS; + /* Record the alternate register class; i.e., a class for which every register in it is better than using memory. If adding a class would make a smaller class (i.e., no union of just those @@ -1524,7 +1529,7 @@ record_reg_classes (int n_alts, int n_ops, rtx *ops, to what we would add if this register were not in the appropriate class. */ - if (reg_pref) + if (reg_pref && reg_pref[REGNO (op)].prefclass != NO_REGS) alt_cost += (may_move_in_cost[mode] [(unsigned char) reg_pref[REGNO (op)].prefclass] @@ -1750,7 +1755,7 @@ record_reg_classes (int n_alts, int n_ops, rtx *ops, to what we would add if this register were not in the appropriate class. */ - if (reg_pref) + if (reg_pref && reg_pref[REGNO (op)].prefclass != NO_REGS) alt_cost += (may_move_in_cost[mode] [(unsigned char) reg_pref[REGNO (op)].prefclass] @@ -1836,7 +1841,8 @@ record_reg_classes (int n_alts, int n_ops, rtx *ops, int class; unsigned int nr; - if (regno >= FIRST_PSEUDO_REGISTER && reg_pref != 0) + if (regno >= FIRST_PSEUDO_REGISTER && reg_pref != 0 + && reg_pref[regno].prefclass != NO_REGS) { enum reg_class pref = reg_pref[regno].prefclass; |