[clang] [compiler-rt] [llvm] [PGO] Initialize GCOV Writeout and Reset Functions in the Runtime on AIX (PR #108570)

[Hubert Tong via cfe-commits]

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+; Tests if the __llvm_gcov_ctr section contains a .ref pseudo-op
+; referring to the __llvm_covinit section.
+; RUN: llc < %s | FileCheck --check-prefixes=CHECK,CHECK-RW %s
+; RUN: llc -mxcoff-roptr < %s | FileCheck --check-prefixes=CHECK,CHECK-RO %s
+
+target datalayout = "E-m:a-p:32:32-Fi32-i64:64-n32"
+target triple = "powerpc-ibm-aix"
+
+; CHECK-RW: .csect __llvm_covinit[RW],3
+; CHECK-RO: .csect __llvm_covinit[RO],3
+; CHECK:         .vbyte  4, __llvm_gcov_writeout[DS]
+; CHECK-NEXT:    .vbyte  4, __llvm_gcov_reset[DS]
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hubert-reinterpretcast wrote:

> Could you help me understand why this is the case? The intention of the test is to make sure that the `__llvm_covinit` csect has the correct storage mapping class and contents. That's why the test includes the `csect` directive.

I meant it is important that we guard against active-csect changing directives in the middle. Meaning that my suggestion was to avoid skipping the two lines in the middle.

https://github.com/llvm/llvm-project/pull/108570