Enable RVV if qemu is detected

- include a fix for jpeg unittests to do at least 1 iteration
- include a fix for scale uv to only use linearup2 if filter is linear

Tested on qemu with Intel host:
[ RUN      ] LibYUVBaseTest.TestCpuHas
Cpu Flags 805306369
Has RISCV 268435456
Has RVV 536870912
Has RVVZVFH 0
Has X86 0

Bug: libyuv:956, libyuv:959, libyuv:960
Change-Id: I4a1b66f83d82ba127780f52526153d586db90111
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/4429570
Commit-Queue: Frank Barchard <fbarchard@chromium.org>
Reviewed-by: Randall Bosetti <rlb@google.com>

1 files changed, 11 insertions, 1 deletions

diff --git a/source/cpu_id.cc b/source/cpu_id.cc
index efad1b36..d5202c8d 100644
--- a/source/cpu_id.cc
+++ b/source/cpu_id.cc
@@ -196,9 +196,13 @@ LIBYUV_API SAFEBUFFERS int RiscvCpuCaps(const char* cpuinfo_name) {
   int flag = 0x0;
   FILE* f = fopen(cpuinfo_name, "re");
   if (!f) {
-    // Assume nothing if /proc/cpuinfo is unavailable.
+#if defined(__riscv_vector)
+    // Assume RVV if /proc/cpuinfo is unavailable.
     // This will occur for Chrome sandbox for Pepper or Render process.
+    return kCpuHasRVV;
+#else
     return 0;
+#endif
   }
   while (fgets(cpuinfo_line, sizeof(cpuinfo_line) - 1, f)) {
     if (memcmp(cpuinfo_line, "isa", 3) == 0) {
@@ -243,6 +247,12 @@ LIBYUV_API SAFEBUFFERS int RiscvCpuCaps(const char* cpuinfo_name) {
         }
       }
     }
+#if defined(__riscv_vector)
+    else if ((memcmp(cpuinfo_line, "vendor_id\t: GenuineIntel", 24) == 0) ||
+             (memcmp(cpuinfo_line, "vendor_id\t: AuthenticAMD", 24) == 0)) {
+      flag |= kCpuHasRVV;
+    }
+#endif
   }
   fclose(f);
   return flag;