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Mark unlikely calls in LLVM as cold #1169

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Mark unlikely calls in LLVM as cold #1169

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4d7f26f
Mark unlikely calls in LLVM as cold
jiribenes Oct 29, 2025
fd19a56
Fix syntax
jiribenes Oct 29, 2025
b27b651
Fix syntax again
jiribenes Oct 29, 2025
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4 changes: 2 additions & 2 deletions libraries/llvm/forward-declare-c.ll
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Original file line number Diff line number Diff line change
Expand Up @@ -6,8 +6,8 @@ declare %Pos @c_get_arg(i64)
declare void @c_io_println(%Pos)
declare %Pos @c_io_readln()

declare void @hole(i8*)
declare void @duplicated_prompt()
declare void @hole(i8*) cold
declare void @duplicated_prompt() cold
Comment on lines +9 to +10
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@jiribenes jiribenes Oct 29, 2025

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My hypothesis is that the hole (panic: not implemented yet) being cold doesn't matter at all, but the duplicated_prompt might by a tiny bit since I assuming used stacks are non-null seems good...


declare %Pos @c_ref_fresh(%Pos)
declare %Pos @c_ref_get(%Pos)
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2 changes: 2 additions & 0 deletions libraries/llvm/panic.c
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Expand Up @@ -7,11 +7,13 @@
// this should _morally_ be using `stderr`, but we don't tee it in tests
// see PR #823 & issue #815 for context

__attribute__((cold))
void hole(const char* message) {
printf("PANIC: %s not implemented yet\n", message);
exit(1);
}

__attribute__((cold))
void duplicated_prompt() {
printf("PANIC: Continuation invoked itself\n");
exit(1);
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2 changes: 1 addition & 1 deletion libraries/llvm/rts.ll
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Expand Up @@ -407,7 +407,7 @@ define private void @invalidate(%Stack %stack, %Stack %end) {

error:
call void @duplicated_prompt()
ret void
unreachable

check:
%isEnd = icmp eq %Stack %next, %end
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