[flang-commits] [compiler-rt] [flang] [llvm] [AArch64] fix trampoline implementation: use X15 (PR #126743)

[Eli Friedman via flang-commits]

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@@ -20903,7 +20903,12 @@ sufficiently aligned block of memory; this memory is written to by the
 intrinsic. Note that the size and the alignment are target-specific -
 LLVM currently provides no portable way of determining them, so a
 front-end that generates this intrinsic needs to have some
-target-specific knowledge. The ``func`` argument must hold a function.
+target-specific knowledge.
+
+The ``func`` argument must be a constant (potentially bitcasted) pointer to a
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efriedma-quic wrote:

How are bitcasts relevant here?

Probably we should tighten the verifier check to just require a function.  And if some target eventually needs trampolines where any of the operands is in a non-zero address-space, we can make the intrinsic overloaded.

Probably we also should tighten llvm::canReplaceOperandWithVariable.

And please land this separately.

https://github.com/llvm/llvm-project/pull/126743