tests/tcg/ppc64le: added speed test

Added test that runs only instruction that were already ported to
decodetree, so we can evaluate the speed difference between using the
legacy system and decodetree.

Signed-off-by: Bruno Larsen (billionai) <[email protected]>

Author: Bruno Larsen (billionai)

tests/tcg/ppc64le/speedTest.c

@@ -0,0 +1,28 @@
+#include <stdint.h>
+
+/*
+ * This code is only useful for testing speed difference between 2 qemu
+ * instances, to see if there are significant speed differences.
+ *
+ * Was mainly used to see if moving to decodetree had an appreciable
+ * speed difference. In this big loop, the final time difference was about
+ * 0.5% faster on decodetree
+ */
+
+int main(){
+    volatile uint64_t i,max,one;
+    i = 0;
+    max = 1;
+    max <<=38;
+    one = 1;
+    __asm__("ld     2, %[um]\n\t": [um] "=m" (one));
+    __asm__("loop:          \n\t");
+    __asm__("ld     0, %[ii]\n\t": [ii] "=m" (i));
+    __asm__("ld     1, %[mm]\n\t": [mm] "=m" (max));
+    __asm__("add    0, 0, 2 \n\t");
+    __asm__("cmpd   0, 1    \n\t");
+    __asm__("std    0, %[ii]\n\t": [ii] "=m" (i));
+    __asm__("std    1, %[mm]\n\t": [mm] "=m" (max));
+    __asm__("blt    loop    \n\t");
+    return 0;
+}