lock user-mode and semantic-bugs

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+Sparc: fdtox/fqtox instructions incorrectly select destination register
+Description of problem:
+This bug report is mostly for informational purposes as I will be posting a fix for the bug.
+
+The `fdtox` and `fqtox` instructions incorrectly select the destination register when the destination register is higher than `f31`.
+Steps to reproduce:
+1. Install Sparc cross compiler `gcc-12-sparc64-linux-gnu`(in Debian)
+2. Compile the test program using `sparc64-linux-gnu-gcc-12 -m64 -o test_program -static test_program.c`
+3. Run the test program using `qemu-sparc64-static ./test_program`
+4. Expected output is 60. Prints 0 instead.
+Additional information:
+Test program to test the issue:
+
+```c
+#include <stdio.h>
+
+int main(int argc, char** argv) {
+    long long truncated = 0;
+    __asm__("fdtox %0,%%f32\n\t" :: "f"(60.0));
+    __asm__("fmovd %%f32,%0\n\t" : "=f"(truncated));
+    printf("%lld\n", truncated);
+    return 0;
+}
+```
+
+The issue is caused by the commit 0bba7572d4. Where certain changes were made in the way destination registers are selected(moving the DFPREG/QFPREG to decodetree).