[CodeGen] Assign SHT_LLVM_LTO to .llvm.lto section

[MaskRay]

This follows up to SHT_LLVM_LTO (https://reviews.llvm.org/D153215) and
resolves the comment of the FatLTO patch
https://reviews.llvm.org/D146776#4430626

[llvmbot]

@llvm/pr-subscribers-clang

@llvm/pr-subscribers-backend-x86

Author: Fangrui Song (MaskRay)

Changes

This follows up to SHT_LLVM_LTO (https://reviews.llvm.org/D153215) and
resolves the comment of the FatLTO patch
https://reviews.llvm.org/D146776#4430626

---

Full diff: https://github.com/llvm/llvm-project/pull/92856.diff

3 Files Affected:

• (modified) clang/test/CodeGen/fat-lto-objects.c (+1-1)
• (modified) llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp (+2)
• (modified) llvm/test/CodeGen/X86/fat-lto-section.ll (+1-1)

diff --git a/clang/test/CodeGen/fat-lto-objects.c b/clang/test/CodeGen/fat-lto-objects.c
index b50567c024fc8..36a73684e7bfe 100644
--- a/clang/test/CodeGen/fat-lto-objects.c
+++ b/clang/test/CodeGen/fat-lto-objects.c
@@ -62,7 +62,7 @@
 
 // ELF: .llvm.lto
 
-//      ASM: .section        .llvm.lto,"e",@progbits
+//      ASM: .section        .llvm.lto,"e",@llvm_lto
 // ASM-NEXT: .Lllvm.embedded.object:
 // ASM-NEXT:        .asciz  "BC
 // ASM-NEXT: .size   .Lllvm.embedded.object
diff --git a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index 3e1897ce670a6..0fc915d89f6c0 100644
--- a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -523,6 +523,8 @@ static unsigned getELFSectionType(StringRef Name, SectionKind K) {
 
   if (hasPrefix(Name, ".llvm.offloading"))
     return ELF::SHT_LLVM_OFFLOADING;
+  if (Name == ".llvm.lto")
+    return ELF::SHT_LLVM_LTO;
 
   if (K.isBSS() || K.isThreadBSS())
     return ELF::SHT_NOBITS;
diff --git a/llvm/test/CodeGen/X86/fat-lto-section.ll b/llvm/test/CodeGen/X86/fat-lto-section.ll
index 30c56229a0e2a..f3ca8436affb4 100644
--- a/llvm/test/CodeGen/X86/fat-lto-section.ll
+++ b/llvm/test/CodeGen/X86/fat-lto-section.ll
@@ -5,6 +5,6 @@
 ; RUN:   | FileCheck %s --check-prefix=EXCLUDE
 
 ; EXCLUDE: Name               Type     {{.*}} ES Flg Lk Inf Al
-; EXCLUDE: .llvm.lto          PROGBITS {{.*}} 00   E  0   0  1
+; EXCLUDE: .llvm.lto          LLVM_LTO {{.*}} 00   E  0   0  1
 
 @a = global i32 1

[MaskRay]

@ilovepi I just realized that the FatLTO LLVM patch did not incorporate https://reviews.llvm.org/D153215 . I thought it did... Hope this is not too late.

[ilovepi]

LGTM. I had thought I added you in #92820, but you're still listed as "request". I saw your avatar and just assumed you were a reviewer. Also, I guess I missed the clang test, when I was checking locally, though.

We'll just go w/ your patch, since they're almost identical.

[MaskRay]

Oh, I didn't know #92820! Thanks. Landing...