[compiler-rt] Pr/drop vender feature bits (PR #126460)

[Piyou Chen via llvm-commits]

https://github.com/BeMg created https://github.com/llvm/llvm-project/pull/126460

Address https://github.com/riscv-non-isa/riscv-c-api-doc/pull/101

>From ef5642ee9c3dd195cfabbe6397d16ca45403ef9c Mon Sep 17 00:00:00 2001
From: Piyou Chen <piyou.chen at sifive.com>
Date: Sun, 9 Feb 2025 21:02:32 -0800
Subject: [PATCH 1/2] [RISCV][compiler-rt] Drop __riscv_vendor_feature_bits

---
 compiler-rt/lib/builtins/cpu_model/riscv.c | 18 +++++-------------
 1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/compiler-rt/lib/builtins/cpu_model/riscv.c b/compiler-rt/lib/builtins/cpu_model/riscv.c
index 74534896057ef53..89b587f698578dd 100644
--- a/compiler-rt/lib/builtins/cpu_model/riscv.c
+++ b/compiler-rt/lib/builtins/cpu_model/riscv.c
@@ -14,12 +14,6 @@ struct {
   unsigned long long features[RISCV_FEATURE_BITS_LENGTH];
 } __riscv_feature_bits __attribute__((visibility("hidden"), nocommon));
 
-#define RISCV_VENDOR_FEATURE_BITS_LENGTH 1
-struct {
-  unsigned length;
-  unsigned long long features[RISCV_VENDOR_FEATURE_BITS_LENGTH];
-} __riscv_vendor_feature_bits __attribute__((visibility("hidden"), nocommon));
-
 struct {
   unsigned mvendorid;
   unsigned long long marchid;
@@ -338,11 +332,11 @@ static int FeaturesBitCached = 0;
 void __init_riscv_feature_bits(void *);
 static void __init_riscv_feature_bits_ctor(void) CONSTRUCTOR_ATTRIBUTE;
 
-// A constructor function that sets __riscv_feature_bits, and
-// __riscv_vendor_feature_bits to the right values.  This needs to run
-// only once.  This constructor is given the highest priority and it should
-// run before constructors without the priority set.  However, it still runs
-// after ifunc initializers and needs to be called explicitly there.
+// A constructor function that sets __riscv_feature_bits
+// to the right values.  This needs to run only once.  This constructor is given
+// the highest priority and it should run before constructors without the
+// priority set.  However, it still runs after ifunc initializers and needs to
+// be called explicitly there.
 
 static void CONSTRUCTOR_ATTRIBUTE __init_riscv_feature_bits_ctor(void) {
   __init_riscv_feature_bits(0);
@@ -357,8 +351,6 @@ void __init_riscv_feature_bits(void *PlatformArgs) {
     return;
 
   __riscv_feature_bits.length = RISCV_FEATURE_BITS_LENGTH;
-  __riscv_vendor_feature_bits.length = RISCV_VENDOR_FEATURE_BITS_LENGTH;
-
 #if defined(__linux__)
   struct riscv_hwprobe Hwprobes[] = {
       {RISCV_HWPROBE_KEY_BASE_BEHAVIOR, 0}, {RISCV_HWPROBE_KEY_IMA_EXT_0, 0},

>From 4d49857069733b0e8614c0a4c2a51f79f6167154 Mon Sep 17 00:00:00 2001
From: Piyou Chen <piyou.chen at sifive.com>
Date: Sun, 9 Feb 2025 21:04:09 -0800
Subject: [PATCH 2/2] fixup! format

---
 compiler-rt/lib/builtins/cpu_model/riscv.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/compiler-rt/lib/builtins/cpu_model/riscv.c b/compiler-rt/lib/builtins/cpu_model/riscv.c
index 89b587f698578dd..6879c2ad482641a 100644
--- a/compiler-rt/lib/builtins/cpu_model/riscv.c
+++ b/compiler-rt/lib/builtins/cpu_model/riscv.c
@@ -351,6 +351,7 @@ void __init_riscv_feature_bits(void *PlatformArgs) {
     return;
 
   __riscv_feature_bits.length = RISCV_FEATURE_BITS_LENGTH;
+
 #if defined(__linux__)
   struct riscv_hwprobe Hwprobes[] = {
       {RISCV_HWPROBE_KEY_BASE_BEHAVIOR, 0}, {RISCV_HWPROBE_KEY_IMA_EXT_0, 0},