[llvm] [PreISelIntrinsicLowering] Produce a memset_pattern16 libcall for llvm.experimental.memset.pattern when available (PR #120420)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,69 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -mtriple=x86_64-apple-darwin10.0.0 -passes=pre-isel-intrinsic-lowering -S -o - %s | FileCheck %s
+
+define void @memset_pattern_i128_1_dynvalue(ptr %a, i128 %value) nounwind {
+; CHECK-LABEL: define void @memset_pattern_i128_1_dynvalue(
+; CHECK-SAME: ptr [[A:%.*]], i128 [[VALUE:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:    br i1 false, label %[[SPLIT:.*]], label %[[LOADSTORELOOP:.*]]
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arsenm wrote:

Branch on false? 

https://github.com/llvm/llvm-project/pull/120420