2a43713d7f
Adds examples/1652-platform-asm-indirect-mem.sx exercising a `=*m -> @x`
indirect-memory place output. Currently rejected loudly at lowering
("not yet implemented"); this locks that behavior as a passing test.
The next commit implements indirect-memory outputs and flips this
example to run end-to-end (store-through-pointer → 42).
20 lines
757 B
Plaintext
20 lines
757 B
Plaintext
// ASM stream — indirect-memory (`=*m`) place output. The place address is passed
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// to the asm as a pointer and the asm writes THROUGH it (no return slot): here
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// `str x9, %[out]` stores 42 into `x`'s storage directly. Distinct from a
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// write-through `=` output (which returns a value that is then stored). Mixes a
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// value output and an input below to exercise operand ordering. aarch64-pinned;
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// ir-only elsewhere (the `.ir` locks the `=*m` constraint + `elementtype` attr).
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poke :: () -> i64 {
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x : i64 = 0;
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asm volatile {
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#string ASM
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mov x9, #42
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str x9, %[out]
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ASM,
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[out] "=*m" -> @x,
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clobbers(.x9),
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};
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return x; // 42 — written through the pointer
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}
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main :: () -> i64 { return poke(); }
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