Contribution of PowerPC port (continuation of 422063005)

src/base/cpu.cc

Index: src/base/cpu.cc
diff --git a/src/base/cpu.cc b/src/base/cpu.cc
index e188406f1a21ff72226b17c2332eb7ccd942dd49..16b586366156a0befcb507156ed5c6ba12560ec6 100644
--- a/src/base/cpu.cc
+++ b/src/base/cpu.cc
@@ -16,6 +16,9 @@
 #if V8_OS_QNX
 #include <sys/syspage.h>  // cpuinfo
 #endif
+#if V8_OS_LINUX && V8_HOST_ARCH_PPC
+#include <elf.h>
+#endif
 #if V8_OS_POSIX
 #include <unistd.h>  // sysconf()
 #endif
@@ -291,6 +294,8 @@ static bool HasListItem(const char* list, const char* item) {
 
 #endif  // V8_HOST_ARCH_IA32 || V8_HOST_ARCH_X64
 
+#define UNKNOWN_CACHE_LINE_SIZE 0
+
 CPU::CPU()
     : stepping_(0),
       model_(0),
@@ -301,6 +306,7 @@ CPU::CPU()
       implementer_(0),
       architecture_(0),
       part_(0),
+      cache_line_size_(UNKNOWN_CACHE_LINE_SIZE),
       has_fpu_(false),
       has_cmov_(false),
       has_sahf_(false),
@@ -559,7 +565,66 @@ CPU::CPU()
     delete[] part;
   }
 
+#elif V8_HOST_ARCH_PPC
+
+#ifndef USE_SIMULATOR
+#if V8_OS_LINUX
+  // Read processor info from /proc/self/auxv.
+  char* auxv_cpu_type = NULL;
+  unsigned auxv_cache_line_size = 0;
+  FILE* fp = fopen("/proc/self/auxv", "r");
+  if (fp != NULL) {
+#if V8_TARGET_ARCH_PPC64
+    Elf64_auxv_t entry;
+#else
+    Elf32_auxv_t entry;
 #endif
+    for (;;) {
+      size_t n = fread(&entry, sizeof(entry), 1, fp);
+      if (n == 0 || entry.a_type == AT_NULL) {
+        break;
+      }
+      if (entry.a_type == AT_PLATFORM) {
+        auxv_cpu_type = reinterpret_cast<char*>(entry.a_un.a_val);
+        break;
+      } else if (entry.a_type == AT_DCACHEBSIZE ||
+                 entry.a_type == AT_ICACHEBSIZE ||
+                 entry.a_type == AT_UCACHEBSIZE) {
+        unsigned cachebsize = entry.a_un.a_val;
+        if (cachebsize > 0 &&
+            (auxv_cache_line_size == 0 || cachebsize < auxv_cache_line_size)) {
+          auxv_cache_line_size = cachebsize;
+        }
+      }
+    }
+    fclose(fp);
+  }
+
+  part_ = -1;
+  if (auxv_cpu_type) {
+    if (strcmp(auxv_cpu_type, "power8") == 0) {
+      part_ = PPC_POWER8;
+    } else if (strcmp(auxv_cpu_type, "power7") == 0) {
+      part_ = PPC_POWER7;
+    } else if (strcmp(auxv_cpu_type, "power6") == 0) {
+      part_ = PPC_POWER6;
+    } else if (strcmp(auxv_cpu_type, "power5") == 0) {
+      part_ = PPC_POWER5;
+    } else if (strcmp(auxv_cpu_type, "ppc970") == 0) {
+      part_ = PPC_G5;
+    } else if (strcmp(auxv_cpu_type, "ppc7450") == 0) {
+      part_ = PPC_G4;
+    } else if (strcmp(auxv_cpu_type, "pa6t") == 0) {
+      part_ = PPC_PA6T;
+    }
+  }
+
+  if (auxv_cache_line_size > 0) {
+    cache_line_size_ = auxv_cache_line_size;
+  }
+#endif  // V8_OS_LINUX
+#endif  // !USE_SIMULATOR
+#endif  // V8_HOST_ARCH_PPC
 }
 
 } }  // namespace v8::base