[llvm] [TLI] Add missing ArmPL mappings (PR #78474)

[Maciej Gabka via llvm-commits]

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@@ -943,6 +953,16 @@ TLI_DEFINE_VECFUNC("hypotf", "armpl_vhypotq_f32", FIXED(4), NOMASK, "_ZGV_LLVM_N
 TLI_DEFINE_VECFUNC("hypot", "armpl_svhypot_f64_x",  SCALABLE(2), MASKED, "_ZGVsMxvv")
 TLI_DEFINE_VECFUNC("hypotf", "armpl_svhypot_f32_x", SCALABLE(4), MASKED, "_ZGVsMxvv")
 
+TLI_DEFINE_VECFUNC("ilogb", "armpl_vilogbq_f64", FIXED(2), NOMASK, "_ZGV_LLVM_N2v")
+TLI_DEFINE_VECFUNC("ilogbf", "armpl_vilogbq_f32", FIXED(4), NOMASK, "_ZGV_LLVM_N4v")
+TLI_DEFINE_VECFUNC("ilogb", "armpl_svilogb_f64_x",  SCALABLE(2), MASKED, "_ZGVsMxv")
+TLI_DEFINE_VECFUNC("ilogbf", "armpl_svilogb_f32_x", SCALABLE(4), MASKED, "_ZGVsMxv")
+
+TLI_DEFINE_VECFUNC("ldexp", "armpl_vldexpq_f64", FIXED(2), NOMASK, "_ZGV_LLVM_N2vv")
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mgabka wrote:

why do you think so?
the function is defined as: 
``
double  ldexp( double arg, int exp)
``
both arguments are passed by value, so from the vector function I am expecting to return a vector of results  where each element is multiplied by a different power of 2 (i.e different element of the input exp vector) .

https://github.com/llvm/llvm-project/pull/78474