[lld] [lld] Add support for EC code map. (PR #69101)

[Martin Storsjö via llvm-commits]

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@@ -0,0 +1,57 @@
+# REQUIRES: x86
+
+# Test that merging code section into a data section changes its characteristics.
+
+# RUN: llvm-mc -triple x86_64-windows-msvc %s -filetype=obj -o %t.obj
+# RUN: lld-link -machine:amd64 -dll -noentry -out:%t.dll %t.obj -merge:.testx=.testd -merge:.testx2=.testbss
+# RUN: llvm-readobj --sections %t.dll | FileCheck %s
+
+# CHECK:      Sections [
+# CHECK-NEXT:   Section {
+# CHECK-NEXT:     Number: 1
+# CHECK-NEXT:     Name: .testbss (2E 74 65 73 74 62 73 73)
+# CHECK-NEXT:     VirtualSize: 0xC
+# CHECK-NEXT:     VirtualAddress: 0x1000
+# CHECK-NEXT:     RawDataSize: 512
+# CHECK-NEXT:     PointerToRawData: 0x400
+# CHECK-NEXT:     PointerToRelocations: 0x0
+# CHECK-NEXT:     PointerToLineNumbers: 0x0
+# CHECK-NEXT:     RelocationCount: 0
+# CHECK-NEXT:     LineNumberCount: 0
+# CHECK-NEXT:     Characteristics [ (0xC0000020)
+# CHECK-NEXT:       IMAGE_SCN_CNT_CODE (0x20)
+# CHECK-NEXT:       IMAGE_SCN_MEM_READ (0x40000000)
+# CHECK-NEXT:       IMAGE_SCN_MEM_WRITE (0x80000000)
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mstorsjo wrote:

This is somewhat weird, that the `IMAGE_SCN_CNT_CODE` flag does get brought over, but `IMAGE_SCN_MEM_EXECUTE` doesn't. But if this is how MS link.exe seems to behave, I guess that's fine (and it's probably only used for testing weird corner cases anyway).

https://github.com/llvm/llvm-project/pull/69101