[llvm] Implement the trampoline intrinsics for AIX. (PR #149388)

[Amy Kwan via llvm-commits]

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@@ -1,7 +1,7 @@
-; RUN: not --crash llc -mtriple powerpc-ibm-aix-xcoff < %s 2>&1 | FileCheck %s
-; RUN: not --crash llc -mtriple powerpc64-ibm-aix-xcoff < %s 2>&1 | FileCheck %s
-
-; CHECK: LLVM ERROR: INIT_TRAMPOLINE operation is not supported on AIX.
+; RUN: llc -mtriple powerpc-ibm-aix-xcoff < %s 2>&1 | \
+; RUN: FileCheck %s --check-prefix=32BIT
+; RUN: llc -mtriple powerpc64-ibm-aix-xcoff < %s 2>&1 -mattr=-altivec | \
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amy-kwan wrote:

Might be a silly question, but is the `-mattr=-altivec` necessary?

https://github.com/llvm/llvm-project/pull/149388