meta-xilinx/meta-microblaze/recipes-devtools/gcc/gcc-10/0020-Patch-microblaze-8-stage-pipeline-for-microblaze.patch

From bfdb38133201f7df01d09dc7e7ee3043a35c1d3e Mon Sep 17 00:00:00 2001
From: Mahesh Bodapati <mbodapat@xilinx.com>
Date: Mon, 9 Nov 2020 19:54:39 +0530
Subject: [PATCH 20/54] [Patch, microblaze]: 8-stage pipeline for microblaze

This patch adds the support for the 8-stage pipeline. The new 8-stage
pipeline reduces the latencies of float & integer division drastically

Signed-off-by :Nagaraju Mekala <nmekala@xilix.com>
---
 gcc/config/microblaze/microblaze.c   | 11 ++++
 gcc/config/microblaze/microblaze.h   |  3 +-
 gcc/config/microblaze/microblaze.md  | 79 +++++++++++++++++++++++++++-
 gcc/config/microblaze/microblaze.opt |  4 ++
 4 files changed, 94 insertions(+), 3 deletions(-)

diff --git a/gcc/config/microblaze/microblaze.c b/gcc/config/microblaze/microblaze.c
index 0a4619eec0c..0dc96e481b7 100644
--- a/gcc/config/microblaze/microblaze.c
+++ b/gcc/config/microblaze/microblaze.c
@@ -1840,6 +1840,17 @@ microblaze_option_override (void)
 		   "%<-mcpu=v8.30.a%>");
         TARGET_REORDER = 0;
     }
+  ver = microblaze_version_to_int("v10.0");
+  if (ver < 0)
+    {
+        if (TARGET_AREA_OPTIMIZED_2)
+          warning (0, "-mxl-frequency can be used only with -mcpu=v10.0 or greater");
+    }
+  else
+    {
+        if (TARGET_AREA_OPTIMIZED_2)
+          microblaze_pipe = MICROBLAZE_PIPE_8;
+    }
 
   if (TARGET_MULTIPLY_HIGH && TARGET_SOFT_MUL)
     error ("%<-mxl-multiply-high%> requires %<-mno-xl-soft-mul%>");
diff --git a/gcc/config/microblaze/microblaze.h b/gcc/config/microblaze/microblaze.h
index 8aa3f155790..8a668278337 100644
--- a/gcc/config/microblaze/microblaze.h
+++ b/gcc/config/microblaze/microblaze.h
@@ -27,7 +27,8 @@
 enum pipeline_type
 {
   MICROBLAZE_PIPE_3 = 0,
-  MICROBLAZE_PIPE_5 = 1
+  MICROBLAZE_PIPE_5 = 1,
+  MICROBLAZE_PIPE_8 = 2
 };
 
 #define MICROBLAZE_MASK_NO_UNSAFE_DELAY         0x00000001
diff --git a/gcc/config/microblaze/microblaze.md b/gcc/config/microblaze/microblaze.md
index be8bbda2bfb..c407a81c51e 100644
--- a/gcc/config/microblaze/microblaze.md
+++ b/gcc/config/microblaze/microblaze.md
@@ -35,6 +35,7 @@
   (R_GOT      20)       ;; GOT ptr reg
   (MB_PIPE_3   0)       ;; Microblaze 3-stage pipeline 
   (MB_PIPE_5   1)       ;; Microblaze 5-stage pipeline 
+  (MB_PIPE_8   2)       ;; Microblaze 8-stage pipeline
   (UNSPEC_SET_GOT       101)    ;;
   (UNSPEC_GOTOFF        102)    ;; GOT offset
   (UNSPEC_PLT           103)    ;; jump table
@@ -82,7 +83,7 @@
 ;; bshift 	Shift operations
 
 (define_attr "type"
-  "unknown,branch,jump,call,load,store,move,arith,darith,imul,idiv,icmp,multi,nop,no_delay_arith,no_delay_load,no_delay_store,no_delay_imul,no_delay_move,bshift,fadd,frsub,fmul,fdiv,fcmp,fsl,fsqrt,fcvt,trap"
+  "unknown,branch,jump,call,load,store,move,arith,darith,imul,idiv,icmp,multi,nop,no_delay_arith,no_delay_load,no_delay_store,no_delay_imul,no_delay_move,bshift,fadd,frsub,fmul,fdiv,fcmp,fsl,fsqrt,fcvt,fint,trap"
   (const_string "unknown"))
 
 ;; Main data type used by the insn
@@ -224,6 +225,80 @@
 ;;-----------------------------------------------------------------
 
 
+
+;;----------------------------------------------------------------
+;; Microblaze 8-stage pipeline description (v10.0 and later)
+;;----------------------------------------------------------------
+
+(define_automaton   "mbpipe_8")
+(define_cpu_unit    "mb8_issue,mb8_iu,mb8_wb,mb8_fpu,mb8_fpu_2,mb8_mul,mb8_mul_2,mb8_div,mb8_div_2,mb8_bs,mb8_bs_2" "mbpipe_8")
+
+(define_insn_reservation "mb8-integer" 1
+  (and (eq_attr "type" "branch,jump,call,arith,darith,icmp,nop,no_delay_arith")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_iu,mb8_wb")
+
+(define_insn_reservation "mb8-special-move" 2
+  (and (eq_attr "type" "move")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_iu*2,mb8_wb")
+
+(define_insn_reservation "mb8-mem-load" 3
+  (and (eq_attr "type" "load,no_delay_load")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_iu,mb8_wb")
+
+(define_insn_reservation "mb8-mem-store" 1
+  (and (eq_attr "type" "store,no_delay_store")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_iu,mb8_wb")
+
+(define_insn_reservation "mb8-mul" 3
+  (and (eq_attr "type" "imul,no_delay_imul")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_mul,mb8_mul_2*2,mb8_wb")
+
+(define_insn_reservation "mb8-div" 30
+  (and (eq_attr "type" "idiv")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+    "mb8_issue,mb8_div,mb8_div_2*29,mb8_wb")
+
+(define_insn_reservation "mb8-bs" 2
+  (and (eq_attr "type" "bshift")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+   "mb8_issue,mb8_bs,mb8_bs_2,mb8_wb")
+
+(define_insn_reservation "mb8-fpu-add-sub-mul" 1
+  (and (eq_attr "type" "fadd,frsub,fmul")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_fpu,mb8_wb")
+
+(define_insn_reservation "mb8-fpu-fcmp" 3
+  (and (eq_attr "type" "fcmp")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_fpu,mb8_fpu*2,mb8_wb")
+
+(define_insn_reservation "mb8-fpu-div" 24
+  (and (eq_attr "type" "fdiv")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_fpu,mb8_fpu_2*23,mb8_wb")
+
+(define_insn_reservation "mb8-fpu-sqrt" 23
+  (and (eq_attr "type" "fsqrt")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_fpu,mb8_fpu_2*22,mb8_wb")
+
+(define_insn_reservation "mb8-fpu-fcvt" 1
+  (and (eq_attr "type" "fcvt")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_fpu,mb8_wb")
+
+(define_insn_reservation "mb8-fpu-fint" 2
+  (and (eq_attr "type" "fint")
+       (eq (symbol_ref  "microblaze_pipe") (const_int MB_PIPE_8)))
+  "mb8_issue,mb8_fpu,mb8_wb")
+
+
 ;;----------------------------------------------------------------
 ;; Microblaze 5-stage pipeline description (v5.00.a and later)
 ;;----------------------------------------------------------------                 
@@ -470,7 +545,7 @@
         (fix:SI (match_operand:SF 1 "register_operand" "d")))]
   "TARGET_HARD_FLOAT && TARGET_FLOAT_CONVERT"
   "fint\t%0,%1"
-  [(set_attr "type"     "fcvt")
+  [(set_attr "type"     "fint")
   (set_attr "mode"      "SF")
   (set_attr "length"    "4")])
 
diff --git a/gcc/config/microblaze/microblaze.opt b/gcc/config/microblaze/microblaze.opt
index 725c2fab52a..a29c6f8df90 100644
--- a/gcc/config/microblaze/microblaze.opt
+++ b/gcc/config/microblaze/microblaze.opt
@@ -133,3 +133,7 @@ Data referenced by offset from start of text instead of GOT (with -fPIC/-fPIE).
 
 mxl-mode-xilkernel
 Target
+
+mxl-frequency
+Target Mask(AREA_OPTIMIZED_2)
+Use 8 stage pipeline (frequency optimization)
-- 
2.17.1