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[ELF] Move SHF_LINK_ORDER till OutputSection addresses are known
Sections with the SHF_LINK_ORDER flag must be ordered in the same relative order as the Sections they have a link to. When using a linker script an arbitrary expression may be used for the virtual address of the OutputSection. In some cases the virtual address does not monotonically increase as the OutputSection index increases, so if we base the ordering of the SHF_LINK_ORDER sections on the index then we can get the order wrong. We fix this by moving SHF_LINK_ORDER resolution till after we have created OutputSection virtual addresses. Differential Revision: https://reviews.llvm.org/D79286
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// REQUIRES: x86 | ||
// RUN: llvm-mc --triple=x86_64 -filetype=obj %s -o %t.o | ||
// RUN: echo "SECTIONS { \ | ||
// RUN: . = 0x80000000; \ | ||
// RUN: .linkorder : { *(.linkorder.*) } \ | ||
// RUN: .text : { *(.text) } \ | ||
// RUN: .text.1 0x80000200 : AT(0x1000) { *(.text.1) } \ | ||
// RUN: .text.2 0x80000100 : AT(0x2000) { *(.text.2) } \ | ||
// RUN: } " > %t.script | ||
// RUN: ld.lld --script %t.script %t.o -o %t | ||
// RUN: llvm-readobj -x .linkorder %t | FileCheck %s | ||
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/// When a linker script does not have monotonically increasing addresses | ||
/// the SHF_LINK_ORDER sections should still be in monotonically increasing | ||
/// order. | ||
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// CHECK: Hex dump of section '.linkorder': | ||
// CHECK-NEXT: 0x80000000 0201 | ||
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.section .text.1, "ax", %progbits | ||
.global _start | ||
_start: | ||
nop | ||
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.section .text.2, "ax", %progbits | ||
.byte 0 | ||
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.section .linkorder.1, "ao", %progbits, .text.1 | ||
.byte 1 | ||
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.section .linkorder.2, "ao", %progbits, .text.2 | ||
.byte 2 |