[PATCH 2/2] xtensa: use pre- and postincrement FP load/store when available

[Max Filippov]

Earlier versions of xtensa FPU used to support preincrement FP load and
store instructions (lsiu/ssiu). Recent FPU supports postincrement FP
load and store instructions only (lsip/ssip). Use configuration macro to
decide which version is available.

2014-10-10  Max Filippov  <jcmvbkbc@gmail.com>

gcc/
    * config/xtensa/xtensa.h (TARGET_HARD_FLOAT_POSTINC): new macro.
    * config/xtensa/xtensa.md (*lsiu, *ssiu): add dependency on
    !TARGET_HARD_FLOAT_POSTINC.
    (*lsip, *ssip): new instructions.
---
 gcc/config/xtensa/xtensa.h  |  4 ++++
 gcc/config/xtensa/xtensa.md | 36 ++++++++++++++++++++++++++++++++++--
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/gcc/config/xtensa/xtensa.h b/gcc/config/xtensa/xtensa.h
index c4a8f88..54bfea4 100644
--- a/gcc/config/xtensa/xtensa.h
+++ b/gcc/config/xtensa/xtensa.h
@@ -39,6 +39,9 @@ extern unsigned xtensa_current_frame_size;
 #ifndef XCHAL_HAVE_THREADPTR
 #define XCHAL_HAVE_THREADPTR 0
 #endif
+#ifndef XCHAL_HAVE_FP_POSTINC
+#define XCHAL_HAVE_FP_POSTINC 0
+#endif
 #define TARGET_BIG_ENDIAN	XCHAL_HAVE_BE
 #define TARGET_DENSITY		XCHAL_HAVE_DENSITY
 #define TARGET_MAC16		XCHAL_HAVE_MAC16
@@ -55,6 +58,7 @@ extern unsigned xtensa_current_frame_size;
 #define TARGET_HARD_FLOAT_RECIP	XCHAL_HAVE_FP_RECIP
 #define TARGET_HARD_FLOAT_SQRT	XCHAL_HAVE_FP_SQRT
 #define TARGET_HARD_FLOAT_RSQRT	XCHAL_HAVE_FP_RSQRT
+#define TARGET_HARD_FLOAT_POSTINC XCHAL_HAVE_FP_POSTINC
 #define TARGET_ABS		XCHAL_HAVE_ABS
 #define TARGET_ADDX		XCHAL_HAVE_ADDX
 #define TARGET_RELEASE_SYNC	XCHAL_HAVE_RELEASE_SYNC
diff --git a/gcc/config/xtensa/xtensa.md b/gcc/config/xtensa/xtensa.md
index 0e3f033..b8acebb 100644
--- a/gcc/config/xtensa/xtensa.md
+++ b/gcc/config/xtensa/xtensa.md
@@ -922,7 +922,7 @@
 			 (match_operand:SI 2 "fpmem_offset_operand" "i"))))
    (set (match_dup 1)
 	(plus:SI (match_dup 1) (match_dup 2)))]
-  "TARGET_HARD_FLOAT"
+  "TARGET_HARD_FLOAT && !TARGET_HARD_FLOAT_POSTINC"
 {
   if (TARGET_SERIALIZE_VOLATILE && volatile_refs_p (PATTERN (insn)))
     output_asm_insn ("memw", operands);
@@ -938,7 +938,7 @@
 	(match_operand:SF 2 "register_operand" "f"))
    (set (match_dup 0)
 	(plus:SI (match_dup 0) (match_dup 1)))]
-  "TARGET_HARD_FLOAT"
+  "TARGET_HARD_FLOAT && !TARGET_HARD_FLOAT_POSTINC"
 {
   if (TARGET_SERIALIZE_VOLATILE && volatile_refs_p (PATTERN (insn)))
     output_asm_insn ("memw", operands);
@@ -948,6 +948,38 @@
    (set_attr "mode"	"SF")
    (set_attr "length"	"3")])
 
+(define_insn "*lsip"
+  [(set (match_operand:SF 0 "register_operand" "=f")
+	(mem:SF (match_operand:SI 1 "register_operand" "+a")))
+   (set (match_dup 1)
+	(plus:SI (match_dup 1)
+		 (match_operand:SI 2 "fpmem_offset_operand" "i")))]
+  "TARGET_HARD_FLOAT && TARGET_HARD_FLOAT_POSTINC"
+{
+  if (TARGET_SERIALIZE_VOLATILE && volatile_refs_p (PATTERN (insn)))
+    output_asm_insn ("memw", operands);
+  return "lsip\t%0, %1, %2";
+}
+  [(set_attr "type"	"fload")
+   (set_attr "mode"	"SF")
+   (set_attr "length"	"3")])
+
+(define_insn "*ssip"
+  [(set (mem:SF (match_operand:SI 0 "register_operand" "+a"))
+	(match_operand:SF 1 "register_operand" "f"))
+   (set (match_dup 0)
+	(plus:SI (match_dup 0)
+		 (match_operand:SI 2 "fpmem_offset_operand" "i")))]
+  "TARGET_HARD_FLOAT && TARGET_HARD_FLOAT_POSTINC"
+{
+  if (TARGET_SERIALIZE_VOLATILE && volatile_refs_p (PATTERN (insn)))
+    output_asm_insn ("memw", operands);
+  return "ssip\t%1, %0, %2";
+}
+  [(set_attr "type"	"fstore")
+   (set_attr "mode"	"SF")
+   (set_attr "length"	"3")])
+
 ;; 64-bit floating point moves
 
 (define_expand "movdf"
-- 
1.8.1.4