[llvm] [IR] Add `llvm.modf` intrinsic (PR #121948)

[Paul Walker via llvm-commits]

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@@ -0,0 +1,57 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --filter "(bl|ptrue)" --version 5
+; RUN: llc -mtriple=aarch64-gnu-linux -mattr=+neon,+sve -vector-library=sleefgnuabi < %s | FileCheck %s -check-prefix=SLEEF
+; RUN: llc -mtriple=aarch64-gnu-linux -mattr=+neon,+sve -vector-library=ArmPL < %s | FileCheck %s -check-prefix=ARMPL
+
+define <4 x float> @test_modf_v4f32(<4 x float> %x, ptr %out_integral) {
+; SLEEF-LABEL: test_modf_v4f32:
+; SLEEF:    bl _ZGVnN4vl4_modff
+;
+; ARMPL-LABEL: test_modf_v4f32:
+; ARMPL:    bl armpl_vmodfq_f32
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paulwalker-arm wrote:

I'd rather see the full output here because the code goes to some trouble to ensure the IR stores are merged with the library call and so it seems prudent to verify that happens.  Perhaps worth having some negative tests (e.g. where %out_integral is loaded from after the call but before the IR store) unless that scenario is already covered elsewhere?

https://github.com/llvm/llvm-project/pull/121948