1 files changed, 31 insertions, 0 deletions

diff --git a/gitlab/issues/target_i386/host_missing/accel_TCG/984.toml b/gitlab/issues/target_i386/host_missing/accel_TCG/984.toml
new file mode 100644
index 00000000..f8b5a6da
--- /dev/null
+++ b/gitlab/issues/target_i386/host_missing/accel_TCG/984.toml
@@ -0,0 +1,31 @@
+id = 984
+title = "QEMU i386 fldl instruction is affected by the precision control bits of the FPU control word"
+state = "opened"
+created_at = "2022-04-15T10:24:44.938Z"
+closed_at = "n/a"
+labels = ["Softfloat", "accel: TCG", "target: i386"]
+url = "https://gitlab.com/qemu-project/qemu/-/issues/984"
+host-os = "Ubuntu 20.04"
+host-arch = "x86_64"
+qemu-version = "v6.1.0..v7.0.0-rc4"
+guest-os = "n/a"
+guest-arch = "n/a"
+description = """~~The QEMU softfloat float64_to_floatx80 implementation is broken and does not produce correct results.~~ QEMU i386 fldl instruction is affected by the precision control bits of the FPU control word.
+
+```
+IN = 1234.567890 (0x40934a4584f4c6e7)
+OUT = 1234.567871 (0x40099a522c0000000000)
+```
+
+This bug was introduced in the QEMU commit qemu/qemu@8ae5719 as part of the switchover to FloatParts, and is still present in the latest tag (v7.0.0-rc4 as of now).
+
+Prior to the offending commit:
+
+```
+IN = 1234.567890 (0x40934a4584f4c6e7)
+OUT = 1234.567890 (0x40099a522c27a6373800)
+```
+
+This breaks the i386 emulation of `fldl st(0)` (`helper_fldl_ST0`)."""
+reproduce = """Call `float64_to_floatx80` with the input value of `1234.567890 (0x40934a4584f4c6e7)` and see the returned result."""
+additional = """See https://github.com/zephyrproject-rtos/sdk-ng/issues/461"""