[PATCH 3/6] Arm: Add GCC_CPUINFO override

[Tamar Christina]

Hi All,

This adds an in intentionally undocumented environment variable
GCC_CPUINFO which can be used to test -mcpu=native.

Tests using these are added later on.

Bootstrapped Regtested on arm-none-linux-gnueabihf and no issues.

Ok for master, GCC 10, 9 and 8?

Thanks,
Tamar

gcc/ChangeLog:

        * config/arm/driver-arm.c (host_detect_local_cpu): Add GCC_CPUINFO.

-- 

diff --git a/gcc/config/arm/driver-arm.c b/gcc/config/arm/driver-arm.c
index 254e5ba53a6130183cf7561913943765a3a56898..85058f257c9d34f31c395c5d4502f73a7f00625e 100644
--- a/gcc/config/arm/driver-arm.c
+++ b/gcc/config/arm/driver-arm.c
@@ -61,6 +61,7 @@ host_detect_local_cpu (int argc, const char **argv)
   FILE *f = NULL;
   bool arch;
   const struct vendor_cpu *cpu_table = NULL;
+  char *fcpu_info = NULL;
 
   if (argc < 1)
     goto not_found;
@@ -69,7 +70,12 @@ host_detect_local_cpu (int argc, const char **argv)
   if (!arch && strcmp (argv[0], "cpu") != 0 && strcmp (argv[0], "tune"))
     goto not_found;
 
-  f = fopen ("/proc/cpuinfo", "r");
+  fcpu_info = getenv ("GCC_CPUINFO");
+  if (fcpu_info)
+    f = fopen (fcpu_info, "r");
+  else
+    f = fopen ("/proc/cpuinfo", "r");
+
   if (f == NULL)
     goto not_found;