[gcc r13-2940] aarch64: Remove AARCH64_FL_RCPC8_4 [PR107025]

[Richard Sandiford <rsandifo@gcc.gnu.org>]

https://gcc.gnu.org/g:0f244d848cffeda68f0eb4c5bb9c7e629bf2e957

commit r13-2940-g0f244d848cffeda68f0eb4c5bb9c7e629bf2e957
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Thu Sep 29 11:32:53 2022 +0100

    aarch64: Remove AARCH64_FL_RCPC8_4 [PR107025]
    
    AARCH64_FL_RCPC8_4 is an odd-one-out in that it has no associated
    entry in aarch64-option-extensions.def.  This means that, although
    it is internally separated from AARCH64_FL_V8_4A, there is no
    mechanism for turning it on and off individually, independently
    of armv8.4-a.
    
    The only place that the flag was used independently was in the
    entry for thunderx3t110, which enabled it alongside V8_3A.
    As noted in PR107025, this means that any use of the extension
    will fail to assemble.
    
    In the PR trail, Andrew suggested removing the core entry.
    That might be best long-term, but since the barrier for removing
    command-line options without a deprecation period is very high,
    this patch instead just drops the flag from the core entry.
    We'll still produce correct code.
    
    gcc/
            PR target/107025
            * config/aarch64/aarch64.h (oAARCH64_FL_RCPC8_4): Delete.
            (AARCH64_FL_FOR_V8_4A): Update accordingly.
            (AARCH64_ISA_RCPC8_4): Use AARCH64_FL_V8_4A directly.
            * config/aarch64/aarch64-cores.def (thunderx3t110): Remove
            AARCH64_FL_RCPC8_4.

Diff:
---
 gcc/config/aarch64/aarch64-cores.def | 2 +-
 gcc/config/aarch64/aarch64.h         | 5 ++---
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/gcc/config/aarch64/aarch64-cores.def b/gcc/config/aarch64/aarch64-cores.def
index 008b0b8c177..cf500d0a981 100644
--- a/gcc/config/aarch64/aarch64-cores.def
+++ b/gcc/config/aarch64/aarch64-cores.def
@@ -133,7 +133,7 @@ AARCH64_CORE("tsv110",  tsv110, tsv110, V8_2A,  AARCH64_FL_CRYPTO | AARCH64_FL_F
 /* ARMv8.3-A Architecture Processors.  */
 
 /* Marvell cores (TX3). */
-AARCH64_CORE("thunderx3t110",  thunderx3t110,  thunderx3t110, V8_3A,  AARCH64_FL_CRYPTO | AARCH64_FL_RCPC | AARCH64_FL_SM4 | AARCH64_FL_SHA3 | AARCH64_FL_F16FML | AARCH64_FL_RCPC8_4, thunderx3t110, 0x43, 0x0b8, 0x0a)
+AARCH64_CORE("thunderx3t110",  thunderx3t110,  thunderx3t110, V8_3A,  AARCH64_FL_CRYPTO | AARCH64_FL_RCPC | AARCH64_FL_SM4 | AARCH64_FL_SHA3 | AARCH64_FL_F16FML, thunderx3t110, 0x43, 0x0b8, 0x0a)
 
 /* ARMv8.4-A Architecture Processors.  */
 
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index c275548b18e..8ea8e2a3913 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -173,7 +173,6 @@
 #define AARCH64_FL_SM4	      (1 << 17)  /* Has ARMv8.4-A SM3 and SM4.  */
 #define AARCH64_FL_SHA3	      (1 << 18)  /* Has ARMv8.4-a SHA3 and SHA512.  */
 #define AARCH64_FL_F16FML     (1 << 19)  /* Has ARMv8.4-a FP16 extensions.  */
-#define AARCH64_FL_RCPC8_4    (1 << 20)  /* Has ARMv8.4-a RCPC extensions.  */
 
 /* Statistical Profiling extensions.  */
 #define AARCH64_FL_PROFILE    (1 << 21)
@@ -265,7 +264,7 @@
   (AARCH64_FL_FOR_V8_2A | AARCH64_FL_V8_3A | AARCH64_FL_PAUTH)
 #define AARCH64_FL_FOR_V8_4A			\
   (AARCH64_FL_FOR_V8_3A | AARCH64_FL_V8_4A | AARCH64_FL_F16FML \
-   | AARCH64_FL_DOTPROD | AARCH64_FL_RCPC8_4 | AARCH64_FL_FLAGM)
+   | AARCH64_FL_DOTPROD | AARCH64_FL_FLAGM)
 #define AARCH64_FL_FOR_V8_5A			\
   (AARCH64_FL_FOR_V8_4A | AARCH64_FL_V8_5A	\
    | AARCH64_FL_SB | AARCH64_FL_SSBS | AARCH64_FL_PREDRES)
@@ -313,7 +312,7 @@
 #define AARCH64_ISA_SM4	           (aarch64_isa_flags & AARCH64_FL_SM4)
 #define AARCH64_ISA_SHA3	   (aarch64_isa_flags & AARCH64_FL_SHA3)
 #define AARCH64_ISA_F16FML	   (aarch64_isa_flags & AARCH64_FL_F16FML)
-#define AARCH64_ISA_RCPC8_4	   (aarch64_isa_flags & AARCH64_FL_RCPC8_4)
+#define AARCH64_ISA_RCPC8_4	   (aarch64_isa_flags & AARCH64_FL_V8_4A)
 #define AARCH64_ISA_RNG		   (aarch64_isa_flags & AARCH64_FL_RNG)
 #define AARCH64_ISA_V8_5A	   (aarch64_isa_flags & AARCH64_FL_V8_5A)
 #define AARCH64_ISA_TME		   (aarch64_isa_flags & AARCH64_FL_TME)