https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111670
Bug ID: 111670
Summary: H8/300 SX uses incorrect code sequences
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: law at gcc dot gnu.org
Target Milestone: ---
The H8/SX port can create sequences like
(set (mem (autoinc (reg sp)) (reg_sp))
Here autoinc is PRE_DECEMENT or PRE_INCREMENT addressing modes.
Which is invalid RTL.
I believe this is the root cause of the following H8/SX failures in the
testsuite:
h8300-sim/-msx/-mint32: gcc.c-torture/execute/920501-6.c -O1 execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/920501-6.c -Os execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/pr20466-1.c -O1 execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/pr20466-1.c -O2 -flto
-fno-use-linker-plugin -flto-partition=none execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/pr20466-1.c -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/pr39339.c -O2 -flto
-fno-use-linker-plugin -flto-partition=none execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/ssad-run.c -O1 execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/ssad-run.c -Os execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/usad-run.c -O1 execution test
h8300-sim/-msx/-mint32: gcc.c-torture/execute/usad-run.c -Os execution test
I suspect we need to break the "Q" constraint into two variants. One which
allows autoinc addressing modes and the other does not.
For movsi/movhi we would use the version which does not allow autoinc
addressing modes and instead use the Z0/ZA approach like the other H8 variants
are using.
I'm not currently working on this.
