diff options
| author | Christian Krinitsin <mail@krinitsin.com> | 2025-06-30 12:24:58 +0000 |
|---|---|---|
| committer | Christian Krinitsin <mail@krinitsin.com> | 2025-06-30 12:27:06 +0000 |
| commit | 33606b41d35115f887ea688b1a16f2ff85bf2fe4 (patch) | |
| tree | 406b2c7b19a087ba437c68f3dbf0b589fa1d6150 /results/scraper/launchpad-without-comments/1841990 | |
| parent | adedf8771bc4de3113041ca21bd4d0d1c0014b6a (diff) | |
| download | qemu-analysis-33606b41d35115f887ea688b1a16f2ff85bf2fe4.tar.gz qemu-analysis-33606b41d35115f887ea688b1a16f2ff85bf2fe4.zip | |
add launchpad bug reports without comments
Diffstat (limited to 'results/scraper/launchpad-without-comments/1841990')
| -rw-r--r-- | results/scraper/launchpad-without-comments/1841990 | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/results/scraper/launchpad-without-comments/1841990 b/results/scraper/launchpad-without-comments/1841990 new file mode 100644 index 000000000..85052fb6e --- /dev/null +++ b/results/scraper/launchpad-without-comments/1841990 @@ -0,0 +1,38 @@ +instruction 'denbcdq' misbehaving + +Instruction 'denbcdq' appears to have no effect. Test case attached. + +On ppc64le native: +-- +gcc -g -O -mcpu=power9 bcdcfsq.c test-denbcdq.c -o test-denbcdq +$ ./test-denbcdq +0x00000000000000000000000000000000 +0x0000000000000000000000000000000c +0x22080000000000000000000000000000 +$ ./test-denbcdq 1 +0x00000000000000000000000000000001 +0x0000000000000000000000000000001c +0x22080000000000000000000000000001 +$ ./test-denbcdq $(seq 0 99) +0x00000000000000000000000000000064 +0x0000000000000000000000000000100c +0x22080000000000000000000000000080 +-- + +With "qemu-ppc64le -cpu power9" +-- +$ qemu-ppc64le -cpu power9 -L [...] ./test-denbcdq +0x00000000000000000000000000000000 +0x0000000000000000000000000000000c +0x0000000000000000000000000000000c +$ qemu-ppc64le -cpu power9 -L [...] ./test-denbcdq 1 +0x00000000000000000000000000000001 +0x0000000000000000000000000000001c +0x0000000000000000000000000000001c +$ qemu-ppc64le -cpu power9 -L [...] ./test-denbcdq $(seq 100) +0x00000000000000000000000000000064 +0x0000000000000000000000000000100c +0x0000000000000000000000000000100c +-- + +I started looking at the code, but I got confused rather quickly. Could be related to endianness? I think denbcdq arrived on the scene before little-endian was a big deal. Maybe something to do with utilizing implicit floating-point register pairs... I don't think the right data is getting to helper_denbcdq, which would point back to the gen_fprp_ptr uses in dfp-impl.inc.c (GEN_DFP_T_FPR_I32_Rc). (Maybe?) \ No newline at end of file |