[llvm] [AIX][TLS] Produce a faster local-exec access sequence for the "aix-small-tls" global variable attribute (PR #83053)

[zhijian lin via llvm-commits]

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@@ -0,0 +1,197 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 3
+; RUN: llc  -verify-machineinstrs -mcpu=pwr7 -ppc-asm-full-reg-names \
+; RUN:      -mtriple powerpc64-ibm-aix-xcoff < %s \
+; RUN:      | FileCheck %s --check-prefix=CHECK-SMALLCM64
+; RUN: llc  -verify-machineinstrs -mcpu=pwr7 -ppc-asm-full-reg-names \
+; RUN:      -mtriple powerpc64-ibm-aix-xcoff --code-model=large \
+; RUN:      < %s | FileCheck %s --check-prefix=CHECK-LARGECM64
+
+ at mySmallLocalExecTLS6 = external thread_local(localexec) global [60 x i64], align 8
+ at mySmallLocalExecTLS2 = external thread_local(localexec) global [3000 x i64], align 8 #0
+ at MyTLSGDVar = thread_local global [800 x i64] zeroinitializer, align 8
+ at mySmallLocalExecTLS3 = internal thread_local(localexec) global [3000 x i64] zeroinitializer, align 8
+ at mySmallLocalExecTLS4 = internal thread_local(localexec) global [3000 x i64] zeroinitializer, align 8 #0
+ at mySmallLocalExecTLS5 = thread_local(localexec) global [3000 x i64] zeroinitializer, align 8 #0
+ at mySmallLocalExecTLS = thread_local(localexec) local_unnamed_addr global [7800 x i64] zeroinitializer, align 8 #0
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diggerlin wrote:

most of test scenario is duplicated with the PR  https://github.com/llvm/llvm-project/pull/71485 , I have different option of  duplicated test, It may be increase the cost maintain of the test case , if the functionality is changed some day, we have to change all the the test case which test the some functionality.

https://github.com/llvm/llvm-project/pull/83053