From e823c769ff0fd973f7eb16822df988cc427a460c Mon Sep 17 00:00:00 2001
From: Dr-Noob <peibolms@gmail.com>
Date: Thu, 30 Oct 2025 08:33:27 +0100
Subject: [PATCH] Attempting to replace 64-bit mask with bool array

---
 src/common/cpu.h     |  2 +-
 src/common/printer.c | 17 +++++++----------
 src/riscv/riscv.c    | 22 ++++++++++++++++++----
 src/riscv/riscv.h    |  1 +
 4 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/src/common/cpu.h b/src/common/cpu.h
index 1a92624..4db385e 100644
--- a/src/common/cpu.h
+++ b/src/common/cpu.h
@@ -138,7 +138,7 @@ struct features {
 
 struct extensions {
   char* str;
-  uint64_t mask;
+  bool* mask; // allocated at runtime with size RISCV_ISA_EXT_ID_MAX-1
 };
 
 struct cpuInfo {
diff --git a/src/common/printer.c b/src/common/printer.c
index 84e46c8..61426f0 100644
--- a/src/common/printer.c
+++ b/src/common/printer.c
@@ -949,14 +949,7 @@ bool print_cpufetch_arm(struct cpuInfo* cpu, STYLE s, struct color** cs, struct
 #endif
 
 #ifdef ARCH_RISCV
-// https://stackoverflow.com/a/2709523
-uint64_t number_of_bits(uint64_t i) {
-  i = i - ((i >> 1) & 0x5555555555555555);
-  i = (i & 0x3333333333333333) + ((i >> 2) & 0x3333333333333333);
-  return (((i + (i >> 4)) & 0xF0F0F0F0F0F0F0F) * 0x101010101010101) >> 56;
-}
-
-void print_ascii_riscv(struct ascii* art, uint32_t la, int32_t termw, bool use_short, uint64_t extensions_mask) {
+void print_ascii_riscv(struct ascii* art, uint32_t la, int32_t termw, bool use_short, bool* extensions_mask) {
   struct ascii_logo* logo = art->art;
   int attr_to_print = 0;
   int attr_type;
@@ -966,7 +959,7 @@ void print_ascii_riscv(struct ascii* art, uint32_t la, int32_t termw, bool use_s
   int32_t ext_list_size = sizeof(extension_list)/sizeof(extension_list[0]);
   int32_t ext_num = 0;
   int32_t ext_to_print = 0;
-  int32_t num_extensions = number_of_bits(extensions_mask);
+  int32_t num_extensions = get_num_extensions(extensions_mask);
   int32_t space_up = ((int)logo->height - (int)(art->n_attributes_set + num_extensions))/2;
   int32_t space_down = (int)logo->height - (int)(art->n_attributes_set + num_extensions) - (int)space_up;
   uint32_t logo_pos = 0;
@@ -1012,7 +1005,11 @@ void print_ascii_riscv(struct ascii* art, uint32_t la, int32_t termw, bool use_s
       // Print extension
       if(attr_to_print > 0 && art->attributes[attr_to_print-1]->type == ATTRIBUTE_EXTENSIONS && ext_num != num_extensions) {
         // Search for the extension to print
-        while(ext_to_print < ext_list_size && !((extensions_mask >> extension_list[ext_to_print].id) & 1U)) ext_to_print++;
+        printf("ext_to_print: %d\n", ext_to_print);
+
+        while (ext_to_print < ext_list_size && !((extensions_mask[extension_list[ext_to_print].id])))
+          ext_to_print++;
+
         if(ext_to_print == ext_list_size) {
           printBug("print_ascii_riscv: Unable to find the extension to print");
         }
diff --git a/src/riscv/riscv.c b/src/riscv/riscv.c
index 5ae8127..9f7f467 100644
--- a/src/riscv/riscv.c
+++ b/src/riscv/riscv.c
@@ -12,7 +12,7 @@
 #define SET_ISA_EXT_MAP(name, bit)          \
   if(strncmp(multi_letter_extension, name,  \
         multi_letter_extension_len) == 0) { \
-    ext->mask |= 1UL << bit;                \
+    ext->mask[bit] = true;                  \
     maskset = true;                         \
   }                                         \
 
@@ -152,7 +152,7 @@ bool valid_extension(char ext) {
 
 struct extensions* get_extensions_from_str(char* str) {
   struct extensions* ext = emalloc(sizeof(struct extensions));
-  ext->mask = 0;
+  ext->mask = ecalloc((RISCV_ISA_EXT_ID_MAX-1) * sizeof(bool));
   ext->str = NULL;
 
   if(str == NULL) {
@@ -165,6 +165,8 @@ struct extensions* get_extensions_from_str(char* str) {
 
   // Code inspired in Linux kernel (riscv_fill_hwcap):
   // https://elixir.bootlin.com/linux/v6.2.10/source/arch/riscv/kernel/cpufeature.c
+  // Now it seems to be here in riscv_parse_isa_string:
+  // https://elixir.bootlin.com/linux/v6.16/source/arch/riscv/kernel/cpufeature.c
   char* isa = str;
   if (!strncmp(isa, "rv32", 4))
     isa += 4;
@@ -196,7 +198,7 @@ struct extensions* get_extensions_from_str(char* str) {
       // adding it to the mask
       if(valid_extension(*e)) {
         int n = *e - 'a';
-        ext->mask |= 1UL << n;
+        ext->mask[n] = true;
       }
       else {
         printBug("get_extensions_from_str: Invalid extension: '%c'", *e);
@@ -207,6 +209,18 @@ struct extensions* get_extensions_from_str(char* str) {
   return ext;
 }
 
+uint32 get_num_extensions(bool* mask) {
+  uint32 num = 0;
+  for (int i=0; i < RISCV_ISA_EXT_ID_MAX-1; i++) {
+    if (mask[i]) num++;
+  }
+  return num;
+}
+
+bool is_mask_empty(bool* mask) {
+  return get_num_extensions(mask) == 0;
+}
+
 struct cpuInfo* get_cpu_info(void) {
   struct cpuInfo* cpu = malloc(sizeof(struct cpuInfo));
   //init_cpu_info(cpu);
@@ -219,7 +233,7 @@ struct cpuInfo* get_cpu_info(void) {
   cpu->hv = emalloc(sizeof(struct hypervisor));
   cpu->hv->present = false;
   cpu->ext = get_extensions_from_str(ext_str);
-  if(cpu->ext->str != NULL && cpu->ext->mask == 0) return NULL;
+  if(cpu->ext->str != NULL && is_mask_empty(cpu->ext->mask)) return NULL;
   cpu->arch = get_uarch(cpu);
   cpu->soc = get_soc(cpu);
   cpu->freq = get_frequency_info(0);
diff --git a/src/riscv/riscv.h b/src/riscv/riscv.h
index f832cb3..53ff7a3 100644
--- a/src/riscv/riscv.h
+++ b/src/riscv/riscv.h
@@ -196,6 +196,7 @@ static const struct extension extension_list[] = {
 struct cpuInfo* get_cpu_info(void);
 char* get_str_topology(struct cpuInfo* cpu, struct topology* topo);
 char* get_str_extensions(struct cpuInfo* cpu);
+uint32 get_num_extensions(bool* mask);
 void print_debug(struct cpuInfo* cpu);
 
 #endif