Skip to content

x86-64 Pjmptbl: normalize the argument before indexing into the jump table #595

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
xavierleroy wants to merge 3 commits into
base: master
Choose a base branch
from
+13 −4
Open

x86-64 Pjmptbl: normalize the argument before indexing into the jump table #595

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
5222d4c
x86-64 `Pjmptbl`: normalize the argument before indexing into the jum…
xavierleroy Aug 22, 2026
5f232ad
Add non-regression test for the x86-64 `Pjmptbl` issue.
xavierleroy Aug 23, 2026
bc5a65f
RISC-V 64 `Pbtbl`: normalize the argument before indexing into the ju…
xavierleroy Aug 23, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 9 additions & 2 deletions riscV/TargetPrinter.ml
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -522,10 +522,17 @@ module Target : TARGET =
freg rd label lbl comment (camlfloat_of_coqfloat32 f)
| Pbtbl(r, tbl) ->
let lbl = new_label() in
fprintf oc "%s jumptable [ " comment;
fprintf oc "%s pseudoinstr btbl [ " comment;
List.iter (fun l -> fprintf oc "%a " print_label l) tbl;
fprintf oc "]\n";
fprintf oc " sll x5, %a, 2\n" ireg r;
if Archi.ptr64 then begin
(* Zero-extend [r] (a 32-bit integer) to 64-bit
and multiply it by 4. *)
fprintf oc " sll x5, %a, 32\n" ireg r;
fprintf oc " srl x5, x5, 30\n"
end else begin
fprintf oc " sll x5, %a, 2\n" ireg r
end;
fprintf oc " lla x31, %a\n" label lbl;
fprintf oc " add x5, x31, x5\n";
fprintf oc " lw x5, 0(x5)\n";
Expand Down
2 changes: 1 addition & 1 deletion test
Open in desktop
Submodule test updated 2 files
+1 −0 regression/Results/switch
+3 −0 regression/switch.c
4 changes: 3 additions & 1 deletion x86/TargetPrinter.ml
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -752,7 +752,9 @@ module Target(System: SYSTEM):TARGET =
let (tmp1, tmp2) =
if r = RAX then (RDX, RAX) else (RAX, RDX) in
fprintf oc " leaq %a(%%rip), %a\n" label l ireg tmp1;
fprintf oc " movslq (%a, %a, 4), %a\n" ireg tmp1 ireg r ireg tmp2;
(* Normalize r to 32-bit unsigned *)
fprintf oc " movl %a, %a\n" ireg32 r ireg32 tmp2;
fprintf oc " movslq (%a, %a, 4), %a\n" ireg tmp1 ireg tmp2 ireg tmp2;
fprintf oc " addq %a, %a\n" ireg tmp2 ireg tmp1;
fprintf oc " jmp *%a\n" ireg tmp1
end else begin
Expand Down
Loading