[PATCH] D58336: [X86] Fix tls variable lowering issue with large code model

Wed Feb 20 10:41:46 PST 2019

rnk added inline comments.

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Comment at: lib/Target/X86/X86ISelDAGToDAG.cpp:1150
+  // Global TLS addressing is an exception. In the medium code model,
+  // we use can use an mode when RIP wrappers are present.
+  // That signifies access to globals that are known to be "near",
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"a mode"

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Comment at: test/CodeGen/X86/code-model-elf.ll:378

+define dso_local i32 @load_thread_data() #0 {
+; SMALL-STATIC-LABEL: load_thread_data:
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These all look the same. Is that correct for the large code model? I thought in the large code model the GOT would be in a PIC register, which I don't see below. Is that known? Maybe there should be a FIXME comment here if you don't consider that to be in scope of this change.

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Comment at: test/CodeGen/X86/code-model-elf.ll:411
+; LARGE-PIC:       # %bb.0:
+; LARGE-PIC-NEXT:    movq    thread_data at GOTTPOFF(%rip), %rax
+; LARGE-PIC-NEXT:    movl    %fs:(%rax), %eax
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Wouldn't this load need to be through the PIC register?

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D58336/new/

https://reviews.llvm.org/D58336