[gcc r13-2515] C-SKY: Fix expanding of float LE comparing with zero for fpuv3.

[qu <xianmiao@gcc.gnu.org>]

https://gcc.gnu.org/g:eae270beb7741eb6c77be756c9cd048bae87713f

commit r13-2515-geae270beb7741eb6c77be756c9cd048bae87713f
Author: Xianmiao Qu <cooper.qu@linux.alibaba.com>
Date:   Wed Sep 7 17:19:54 2022 +0800

    C-SKY: Fix expanding of float LE comparing with zero for fpuv3.
    
    The original code will cause the warning:
    /usr/lib/gcc-snapshot/bin/g++  -fno-PIE -c   -g -O2   -DIN_GCC  -DCROSS_DIRECTORY_STRUCTURE   -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror -fno-common  -DHAVE_CONFIG_H -I. -I. -I../../gcc/gcc -I../../gcc/gcc/. -I../../gcc/gcc/../include -I../../gcc/gcc/../libcpp/include -I../../gcc/gcc/../libcody  -I../../gcc/gcc/../libdecnumber -I../../gcc/gcc/../libdecnumber/dpd -I../libdecnumber -I../../gcc/gcc/../libbacktrace   -o csky.o -MT csky.o -MMD -MP -MF ./.deps/csky.TPo ../../gcc/gcc/config/csky/csky.cc
    In file included from ../../gcc/gcc/config/csky/csky.h:183,
                    from ./tm.h:20,
                    from ../../gcc/gcc/backend.h:28,
                    from ../../gcc/gcc/config/csky/csky.cc:27:
    ../../gcc/gcc/config/csky/csky.cc: In function 'bool csky_emit_compare_float(rtx_code, rtx, rtx)':
    ../../gcc/gcc/config/csky/csky_isa.h:29:37: error: enum constant in boolean context [-Werror=int-in-bool-context]
      29 | #define CSKY_ISA_FEATURE_DEFINE(x)  isa_bit_ ## x
          |                                     ^~~~~~~~
    ../../gcc/gcc/config/csky/csky_isa.h:30:37: note: in expansion of macro 'CSKY_ISA_FEATURE_DEFINE'
      30 | #define CSKY_ISA_FEATURE_GET(x)     CSKY_ISA_FEATURE_DEFINE (x)
          |                                     ^~~~~~~~~~~~~~~~~~~~~~~
    ../../gcc/gcc/config/csky/csky.cc:6346:43: note: in expansion of macro 'CSKY_ISA_FEATURE_GET'
    6346 |                                        || CSKY_ISA_FEATURE_GET(fpv2_df)
          |                                           ^~~~~~~~~~~~~~~~~~~~
    ../../gcc/gcc/config/csky/csky_isa.h:29:37: error: enum constant in boolean context [-Werror=int-in-bool-context]
      29 | #define CSKY_ISA_FEATURE_DEFINE(x)  isa_bit_ ## x
          |                                     ^~~~~~~~
    ../../gcc/gcc/config/csky/csky_isa.h:30:37: note: in expansion of macro 'CSKY_ISA_FEATURE_DEFINE'
      30 | #define CSKY_ISA_FEATURE_GET(x)     CSKY_ISA_FEATURE_DEFINE (x)
          |                                     ^~~~~~~~~~~~~~~~~~~~~~~
    ../../gcc/gcc/config/csky/csky.cc:6346:43: note: in expansion of macro 'CSKY_ISA_FEATURE_GET'
    6346 |                                        || CSKY_ISA_FEATURE_GET(fpv2_df)
          |                                           ^~~~~~~~~~~~~~~~~~~~
    ../../gcc/gcc/config/csky/csky_isa.h:29:37: error: enum constant in boolean context [-Werror=int-in-bool-context]
      29 | #define CSKY_ISA_FEATURE_DEFINE(x)  isa_bit_ ## x
          |                                     ^~~~~~~~
    ../../gcc/gcc/config/csky/csky_isa.h:30:37: note: in expansion of macro 'CSKY_ISA_FEATURE_DEFINE'
      30 | #define CSKY_ISA_FEATURE_GET(x)     CSKY_ISA_FEATURE_DEFINE (x)
          |                                     ^~~~~~~~~~~~~~~~~~~~~~~
    ../../gcc/gcc/config/csky/csky.cc:6347:43: note: in expansion of macro 'CSKY_ISA_FEATURE_GET'
    6347 |                                        || CSKY_ISA_FEATURE_GET(fpv2_divd)))
          |                                           ^~~~~~~~~~~~~~~~~~~~
    
    The 'CSKY_ISA_FEATURE_DEFINE (x)' is an enum contant, it will cause the condition always being true.
    In addition to warning, it will let FPUV3 to generate a move instruction, which is unnecessary.
    In a simple test case, the move instruction can be combined, so it was not found in the testsuite.
    But in some complex scenarios, this may generate some redundant instructions.
    The correct way is to use 'CSKY_ISA_FEATURE' instead of 'CSKY_ISA_FEATURE_DEFINE'.
    
    gcc/
            * config/csky/csky.cc (csky_emit_compare_float): Fix the expanding of
            float LE comparing with zero for fpuv3.
            * config/csky/csky.h (TARGET_SUPPORT_FPV2): New, true if any fpuv2
            features are enabled.

Diff:
---
 gcc/config/csky/csky.cc | 4 +---
 gcc/config/csky/csky.h  | 4 ++++
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/gcc/config/csky/csky.cc b/gcc/config/csky/csky.cc
index a7dc6cefead..4dc74d8924f 100644
--- a/gcc/config/csky/csky.cc
+++ b/gcc/config/csky/csky.cc
@@ -6342,9 +6342,7 @@ csky_emit_compare_float (enum rtx_code code, rtx op0, rtx op1)
     case GT:
     case LT:
     case LE:
-      if (op1 == CONST0_RTX (mode) && (CSKY_ISA_FEATURE_GET(fpv2_sf)
-				       || CSKY_ISA_FEATURE_GET(fpv2_df)
-				       || CSKY_ISA_FEATURE_GET(fpv2_divd)))
+      if (op1 == CONST0_RTX (mode) && TARGET_SUPPORT_FPV2)
 	op1 = force_reg (mode, op1);
       break;
     case ORDERED:
diff --git a/gcc/config/csky/csky.h b/gcc/config/csky/csky.h
index 37410f0cda4..f786ad55d43 100644
--- a/gcc/config/csky/csky.h
+++ b/gcc/config/csky/csky.h
@@ -165,6 +165,10 @@
 			     || CSKY_ISA_FEATURE (fpv3_sf) \
 			     || CSKY_ISA_FEATURE (fpv3_df))
 
+#define TARGET_SUPPORT_FPV2 (CSKY_ISA_FEATURE(fpv2_sf)    \
+			     || CSKY_ISA_FEATURE(fpv2_df) \
+			     || CSKY_ISA_FEATURE(fpv2_divd))
+
 /* Number of loads/stores handled by ldm/stm.  */
 #define CSKY_MIN_MULTIPLE_STLD	3
 #define CSKY_MAX_MULTIPLE_STLD	12