[clang] [llvm] [X86] Add Support for X86 TLSDESC Relocations (PR #83136)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,165 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc < %s -mtriple=i686-unknown-unknown --relocation-model=pic -enable-tlsdesc | FileCheck %s --check-prefix=X86
+; RUN: llc < %s -mtriple=x86_64-pc-linux-gnux32 --relocation-model=pic -enable-tlsdesc | FileCheck %s --check-prefix=X32
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown --relocation-model=pic -enable-tlsdesc | FileCheck %s --check-prefix=X64
+
+ at x = thread_local global i32 0, align 4
+ at y = internal thread_local global i32 0, align 4
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MaskRay wrote:

GCC's x86-64 port assumes that FLAGS_REG and RAX are changed while all other registers are preserved.

Ideally, show that some registers are not clobbered.

https://github.com/llvm/llvm-project/pull/83136