hipe: Add hipe_regalloc_prepass

hipe_regalloc_prepass speeds up register allocation by spilling any temp
that is live over a call (which clobbers all register).

In order to detect these, a new function was added to the target
interface; defines_all_alloc/1, that takes an instruction and returns a
boolean.

2 files changed, 9 insertions, 0 deletions

diff --git a/lib/hipe/ppc/hipe_ppc_defuse.erl b/lib/hipe/ppc/hipe_ppc_defuse.erl
index 77b84dc574..305e88488d 100644
--- a/lib/hipe/ppc/hipe_ppc_defuse.erl
+++ b/lib/hipe/ppc/hipe_ppc_defuse.erl
@@ -22,6 +22,7 @@
 -module(hipe_ppc_defuse).
 -export([insn_def_all/1, insn_use_all/1]).
 -export([insn_def_gpr/1, insn_use_gpr/1]).
+-export([insn_defs_all_gpr/1, insn_defs_all_fpr/1]).
 -export([insn_def_fpr/1, insn_use_fpr/1]).
 -include("hipe_ppc.hrl").
 
@@ -52,6 +53,9 @@ insn_def_gpr(I) ->
     _ -> []
   end.
 
+insn_defs_all_gpr(#pseudo_call{}) -> true;
+insn_defs_all_gpr(_) -> false.
+
 call_clobbered_gpr() ->
   [hipe_ppc:mk_temp(R, T)
    || {R,T} <- hipe_ppc_registers:call_clobbered() ++ all_fp_pseudos()].
@@ -116,6 +120,9 @@ insn_def_fpr(I) ->
     _ -> []
   end.
 
+insn_defs_all_fpr(#pseudo_call{}) -> true;
+insn_defs_all_fpr(_) -> false.
+
 call_clobbered_fpr() ->
   [hipe_ppc:mk_temp(R, 'double') || R <- hipe_ppc_registers:allocatable_fpr()].
 
diff --git a/lib/hipe/ppc/hipe_ppc_registers.erl b/lib/hipe/ppc/hipe_ppc_registers.erl
index f4781d5ed7..8f6d9779fc 100644
--- a/lib/hipe/ppc/hipe_ppc_registers.erl
+++ b/lib/hipe/ppc/hipe_ppc_registers.erl
@@ -201,6 +201,8 @@ is_arg(R) ->
     _ -> false
   end.
 
+%% Note: the fact that allocatable_gpr() is a subset of call_clobbered() is
+%% hard-coded in hipe_ppc_defuse:insn_defs_all_gpr/1
 call_clobbered() ->		% does the RA strip the type or not?
   [{?R0,tagged},{?R0,untagged},
    %% R1 is reserved for C