[PATCH v2] LoongArch: Fix incorrect code generation for sad pattern

[Jiahao Xu]

When I attempt to enable vect_usad_char effective target for LoongArch, 
slp-reduc-sad.c
and vect-reduc-sad*.c tests fail. These tests fail because the sad pattern 
generates bad
code. This patch to fixed them, for sad patterns, use zero expansion instead of 
sign
expansion for reduction.

Currently, we are fixing failed vectorized tests, and in the future, we will
enable more tests of "vect" for LoongArch.

gcc/ChangeLog:

        * config/loongarch/lasx.md: Use zero expansion instruction.
        * config/loongarch/lsx.md: Ditto.

diff --git a/gcc/config/loongarch/lasx.md b/gcc/config/loongarch/lasx.md
index eeac8cd984b..db6871507e2 100644
--- a/gcc/config/loongarch/lasx.md
+++ b/gcc/config/loongarch/lasx.md
@@ -5097,8 +5097,8 @@ (define_expand "usadv32qi"
   rtx t2 = gen_reg_rtx (V16HImode);
   rtx t3 = gen_reg_rtx (V8SImode);
   emit_insn (gen_lasx_xvabsd_u_bu (t1, operands[1], operands[2]));
-  emit_insn (gen_lasx_xvhaddw_h_b (t2, t1, t1));
-  emit_insn (gen_lasx_xvhaddw_w_h (t3, t2, t2));
+  emit_insn (gen_lasx_xvhaddw_hu_bu (t2, t1, t1));
+  emit_insn (gen_lasx_xvhaddw_wu_hu (t3, t2, t2));
   emit_insn (gen_addv8si3 (operands[0], t3, operands[3]));
   DONE;
 })
@@ -5114,8 +5114,8 @@ (define_expand "ssadv32qi"
   rtx t2 = gen_reg_rtx (V16HImode);
   rtx t3 = gen_reg_rtx (V8SImode);
   emit_insn (gen_lasx_xvabsd_s_b (t1, operands[1], operands[2]));
-  emit_insn (gen_lasx_xvhaddw_h_b (t2, t1, t1));
-  emit_insn (gen_lasx_xvhaddw_w_h (t3, t2, t2));
+  emit_insn (gen_lasx_xvhaddw_hu_bu (t2, t1, t1));
+  emit_insn (gen_lasx_xvhaddw_wu_hu (t3, t2, t2));
   emit_insn (gen_addv8si3 (operands[0], t3, operands[3]));
   DONE;
 })
diff --git a/gcc/config/loongarch/lsx.md b/gcc/config/loongarch/lsx.md
index dbdb423011b..5e5e2503636 100644
--- a/gcc/config/loongarch/lsx.md
+++ b/gcc/config/loongarch/lsx.md
@@ -3468,8 +3468,8 @@ (define_expand "usadv16qi"
   rtx t2 = gen_reg_rtx (V8HImode);
   rtx t3 = gen_reg_rtx (V4SImode);
   emit_insn (gen_lsx_vabsd_u_bu (t1, operands[1], operands[2]));
-  emit_insn (gen_lsx_vhaddw_h_b (t2, t1, t1));
-  emit_insn (gen_lsx_vhaddw_w_h (t3, t2, t2));
+  emit_insn (gen_lsx_vhaddw_hu_bu (t2, t1, t1));
+  emit_insn (gen_lsx_vhaddw_wu_hu (t3, t2, t2));
   emit_insn (gen_addv4si3 (operands[0], t3, operands[3]));
   DONE;
 })
@@ -3485,8 +3485,8 @@ (define_expand "ssadv16qi"
   rtx t2 = gen_reg_rtx (V8HImode);
   rtx t3 = gen_reg_rtx (V4SImode);
   emit_insn (gen_lsx_vabsd_s_b (t1, operands[1], operands[2]));
-  emit_insn (gen_lsx_vhaddw_h_b (t2, t1, t1));
-  emit_insn (gen_lsx_vhaddw_w_h (t3, t2, t2));
+  emit_insn (gen_lsx_vhaddw_hu_bu (t2, t1, t1));
+  emit_insn (gen_lsx_vhaddw_wu_hu (t3, t2, t2));
   emit_insn (gen_addv4si3 (operands[0], t3, operands[3]));
   DONE;
 })
-- 
2.20.1