[llvm] [GlobalISel][AArch64] Add G_FPTOSI_SAT/G_FPTOUI_SAT (PR #96297)

[David Green via llvm-commits]

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@@ -708,6 +708,55 @@ AArch64LegalizerInfo::AArch64LegalizerInfo(const AArch64Subtarget &ST)
       .libcallFor(
           {{s32, s128}, {s64, s128}, {s128, s128}, {s128, s32}, {s128, s64}});
 
+  getActionDefinitionsBuilder({G_FPTOSI_SAT, G_FPTOUI_SAT})
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davemgreen wrote:

Yeah - fptosi_sat is likely to be one of the more complex ones. (Note that in the future scalable vectors and bf16 could also add extra complexity). I do wonder if having to handle every different type combo in these definitions is the best, or whether there should be some overarching definition for types that is applied to every operation before the individual rules kick in.

https://github.com/llvm/llvm-project/pull/96297