AArch64: Add cost table for Cortex-A76

Add an initial cost table for Cortex-A76 - this is copied from
cotexa57_extra_costs but updated based on the Optimization Guide.
Use the new cost table on all Neoverse tunings and ensure the tunings
are consistent for all.  As a result more compact code is generated
with more combined shift+alu operations. Eg. -mcpu=cortex-a76 will now
merge the shifts in:

int f(int x, int y) { return (x & y << 3) * (x | y << 3); }

and  w2, w0, w1, lsl 3
orr  w0, w0, w1, lsl 3
mul  w0, w2, w0
ret

SPEC2017 codesize improves by 0.02% and SPECINT2017 shows 0.24% gain.

2020-11-18  Wilco Dijkstra  <wdijkstr@arm.com>

gcc/
	* config/aarch64/aarch64.c (neoversen1_tunings): Use new
	cortexa76_extra_costs.
	(neoversev1_tunings): Likewise.
	(neoversen2_tunines): Likewise.
	* config/arm/aarch-cost-tables.h (cortexa76_extra_costs):
	add new costs.

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 1cf4900eda5dafd3072b7230b404b9786aef2057..67c25878779c96657f37b1d342407deeaec9250c 100644 (file)
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -1312,7 +1312,7 @@ static const struct tune_params thunderx3t110_tunings =
 
 static const struct tune_params neoversen1_tunings =
 {
-  &cortexa57_extra_costs,
+  &cortexa76_extra_costs,
   &generic_addrcost_table,
   &generic_regmove_cost,
   &cortexa57_vector_cost,
@@ -1338,7 +1338,7 @@ static const struct tune_params neoversen1_tunings =
 
 static const struct tune_params neoversev1_tunings =
 {
-  &cortexa57_extra_costs,
+  &cortexa76_extra_costs,
   &generic_addrcost_table,
   &generic_regmove_cost,
   &cortexa57_vector_cost,
@@ -1364,7 +1364,7 @@ static const struct tune_params neoversev1_tunings =
 
 static const struct tune_params neoversen2_tunings =
 {
-  &cortexa57_extra_costs,
+  &cortexa76_extra_costs,
   &generic_addrcost_table,
   &generic_regmove_cost,
   &cortexa57_vector_cost,

diff --git a/gcc/config/arm/aarch-cost-tables.h b/gcc/config/arm/aarch-cost-tables.h
index cf8186599018cc5e51cf44e4f2080a502d895e1d..1b9d53d07b54bddf1767121236b06d2b4581631c 100644 (file)
--- a/gcc/config/arm/aarch-cost-tables.h
+++ b/gcc/config/arm/aarch-cost-tables.h
@@ -331,6 +331,109 @@ const struct cpu_cost_table cortexa57_extra_costs =
   }
 };
 
+const struct cpu_cost_table cortexa76_extra_costs =
+{
+  /* ALU */
+  {
+    0,                 /* arith.  */
+    0,                 /* logical.  */
+    0,                 /* shift.  */
+    0,                  /* shift_reg.  */
+    COSTS_N_INSNS (1), /* arith_shift.  */
+    COSTS_N_INSNS (1), /* arith_shift_reg.  */
+    0,                /* log_shift.  */
+    COSTS_N_INSNS (1), /* log_shift_reg.  */
+    0,                 /* extend.  */
+    COSTS_N_INSNS (1), /* extend_arith.  */
+    COSTS_N_INSNS (1), /* bfi.  */
+    0,                 /* bfx.  */
+    0,                 /* clz.  */
+    0,                  /* rev.  */
+    0,                 /* non_exec.  */
+    true               /* non_exec_costs_exec.  */
+  },
+  {
+    /* MULT SImode */
+    {
+      COSTS_N_INSNS (1),       /* simple.  */
+      COSTS_N_INSNS (2),       /* flag_setting.  */
+      COSTS_N_INSNS (1),       /* extend.  */
+      COSTS_N_INSNS (1),       /* add.  */
+      COSTS_N_INSNS (1),       /* extend_add.  */
+      COSTS_N_INSNS (6)               /* idiv.  */
+    },
+    /* MULT DImode */
+    {
+      COSTS_N_INSNS (3),       /* simple.  */
+      0,                       /* flag_setting (N/A).  */
+      COSTS_N_INSNS (1),       /* extend.  */
+      COSTS_N_INSNS (3),       /* add.  */
+      COSTS_N_INSNS (1),       /* extend_add.  */
+      COSTS_N_INSNS (10)       /* idiv.  */
+    }
+  },
+  /* LD/ST */
+  {
+    COSTS_N_INSNS (3),         /* load.  */
+    COSTS_N_INSNS (3),         /* load_sign_extend.  */
+    COSTS_N_INSNS (3),         /* ldrd.  */
+    COSTS_N_INSNS (2),         /* ldm_1st.  */
+    1,                         /* ldm_regs_per_insn_1st.  */
+    2,                         /* ldm_regs_per_insn_subsequent.  */
+    COSTS_N_INSNS (4),         /* loadf.  */
+    COSTS_N_INSNS (4),         /* loadd.  */
+    COSTS_N_INSNS (5),         /* load_unaligned.  */
+    0,                         /* store.  */
+    0,                         /* strd.  */
+    0,                         /* stm_1st.  */
+    1,                         /* stm_regs_per_insn_1st.  */
+    2,                         /* stm_regs_per_insn_subsequent.  */
+    0,                         /* storef.  */
+    0,                         /* stored.  */
+    COSTS_N_INSNS (1),         /* store_unaligned.  */
+    COSTS_N_INSNS (1),         /* loadv.  */
+    COSTS_N_INSNS (1)          /* storev.  */
+  },
+  {
+    /* FP SFmode */
+    {
+      COSTS_N_INSNS (10),      /* div.  */
+      COSTS_N_INSNS (2),       /* mult.  */
+      COSTS_N_INSNS (3),       /* mult_addsub.  */
+      COSTS_N_INSNS (3),       /* fma.  */
+      COSTS_N_INSNS (1),       /* addsub.  */
+      0,                       /* fpconst.  */
+      0,                       /* neg.  */
+      0,                       /* compare.  */
+      COSTS_N_INSNS (1),       /* widen.  */
+      COSTS_N_INSNS (1),       /* narrow.  */
+      COSTS_N_INSNS (1),       /* toint.  */
+      COSTS_N_INSNS (1),       /* fromint.  */
+      COSTS_N_INSNS (1)        /* roundint.  */
+    },
+    /* FP DFmode */
+    {
+      COSTS_N_INSNS (15),      /* div.  */
+      COSTS_N_INSNS (2),       /* mult.  */
+      COSTS_N_INSNS (3),       /* mult_addsub.  */
+      COSTS_N_INSNS (3),       /* fma.  */
+      COSTS_N_INSNS (1),       /* addsub.  */
+      0,                       /* fpconst.  */
+      0,                       /* neg.  */
+      0,                       /* compare.  */
+      COSTS_N_INSNS (1),       /* widen.  */
+      COSTS_N_INSNS (1),       /* narrow.  */
+      COSTS_N_INSNS (1),       /* toint.  */
+      COSTS_N_INSNS (1),       /* fromint.  */
+      COSTS_N_INSNS (1)        /* roundint.  */
+    }
+  },
+  /* Vector */
+  {
+    COSTS_N_INSNS (1)  /* alu.  */
+  }
+};
+
 const struct cpu_cost_table exynosm1_extra_costs =
 {
   /* ALU */