LoongArch: Optimize normal immediate data loading.

Ensure that only one register is used when loading immediate values.
The original immediate value load is handled through virtual
registers, resulting in the following load operation
(0x1234567890abcdef):
        lu12i.w $r4,-456004                     # 0xfffffffffff90abc
        or      $r12,$r0,$r0
        ori     $r4,$r4,3567
        lu32i.d $r12,0x45678
        lu32i.d $r4,0
        or      $r4,$r4,$r12
        lu52i.d $r4,$r4,0x123

The optimized sequence is as follows:
	lu12i.w	$r4,-456004			# 0xfffffffffff90abc
	ori	$r4,$r4,3567
	lu32i.d	$r4,0x45678
	lu52i.d	$r4,$r4,0x123

gcc/ChangeLog:

	* config/loongarch/loongarch.cc (loongarch_move_integer):
	No new virtual register is allocated during immediate load.

gcc/testsuite/ChangeLog:

	* gcc.target/loongarch/imm-load.c: Modify.

diff --git a/gcc/config/loongarch/loongarch.cc b/gcc/config/loongarch/loongarch.cc
index 1dce56e46fd17daabf98d43d73b1dc0fe134fe4e..c725d028d8c3275a8677bdd146a8950c52126a57 100644 (file)
--- a/gcc/config/loongarch/loongarch.cc
+++ b/gcc/config/loongarch/loongarch.cc
@@ -3439,13 +3439,8 @@ loongarch_move_integer (rtx temp, rtx dest, unsigned HOST_WIDE_INT value)
   x = GEN_INT (codes[0].value);
   for (i = 1; i < num_ops; i++)
     {
-      if (!can_create_pseudo_p ())
-       {
-         emit_insn (gen_rtx_SET (temp, x));
-         x = temp;
-       }
-      else
-       x = force_reg (mode, x);
+      emit_insn (gen_rtx_SET (temp, x));
+      x = temp;
 
       set_unique_reg_note (get_last_insn (), REG_EQUAL,
                           GEN_INT (codes[i-1].curr_value));

diff --git a/gcc/testsuite/gcc.target/loongarch/imm-load.c b/gcc/testsuite/gcc.target/loongarch/imm-load.c
index 33291fe89bdc52673e9614852f49d037ceb6f005..a125840d5072c01ffefe628298c9f208857052a0 100644 (file)
--- a/gcc/testsuite/gcc.target/loongarch/imm-load.c
+++ b/gcc/testsuite/gcc.target/loongarch/imm-load.c
@@ -7,5 +7,5 @@ test (void)
 {
   return 0x1234567890abcdef;
 }
-/* { dg-final { scan-rtl-dump-times "scanning new insn with uid" 6 "split1" } } */
+/* { dg-final { scan-rtl-dump-times "scanning new insn with uid" 4 "split1" } } */