[llvm] d4e8619 - [CGData] Fix assertions when skipping name (#151570)

[via llvm-commits]

Author: Kyungwoo Lee
Date: 2025-07-31T11:46:02-07:00
New Revision: d4e8619ef12d1de0b839f91c3ee976811823bd7c

URL: https://github.com/llvm/llvm-project/commit/d4e8619ef12d1de0b839f91c3ee976811823bd7c
DIFF: https://github.com/llvm/llvm-project/commit/d4e8619ef12d1de0b839f91c3ee976811823bd7c.diff

LOG: [CGData] Fix assertions when skipping name (#151570)

This fixes assertion failures when using
`-indexed-codegen-data-read-function-map-names=false`

Added: 
    

Modified: 
    llvm/lib/CGData/StableFunctionMapRecord.cpp
    llvm/test/ThinLTO/AArch64/cgdata-merge-read.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CGData/StableFunctionMapRecord.cpp b/llvm/lib/CGData/StableFunctionMapRecord.cpp
index 4e4fceffb52b5..423e068023088 100644
--- a/llvm/lib/CGData/StableFunctionMapRecord.cpp
+++ b/llvm/lib/CGData/StableFunctionMapRecord.cpp
@@ -160,14 +160,18 @@ void StableFunctionMapRecord::deserialize(const unsigned char *&Ptr,
   for (unsigned I = 0; I < NumFuncs; ++I) {
     auto Hash =
         endian::readNext<stable_hash, endianness::little, unaligned>(Ptr);
-    auto FunctionNameId =
+    [[maybe_unused]] auto FunctionNameId =
         endian::readNext<uint32_t, endianness::little, unaligned>(Ptr);
-    assert(FunctionMap->getNameForId(FunctionNameId) &&
-           "FunctionNameId out of range");
-    auto ModuleNameId =
+    [[maybe_unused]] auto ModuleNameId =
         endian::readNext<uint32_t, endianness::little, unaligned>(Ptr);
-    assert(FunctionMap->getNameForId(ModuleNameId) &&
-           "ModuleNameId out of range");
+    // Only validate IDs if we've read the names
+    if (ReadStableFunctionMapNames) {
+      assert(FunctionMap->getNameForId(FunctionNameId) &&
+             "FunctionNameId out of range");
+      assert(FunctionMap->getNameForId(ModuleNameId) &&
+             "ModuleNameId out of range");
+    }
+
     auto InstCount =
         endian::readNext<uint32_t, endianness::little, unaligned>(Ptr);
 

diff  --git a/llvm/test/ThinLTO/AArch64/cgdata-merge-read.ll b/llvm/test/ThinLTO/AArch64/cgdata-merge-read.ll
index da756e7f15e68..9eb9bda0b54d7 100644
--- a/llvm/test/ThinLTO/AArch64/cgdata-merge-read.ll
+++ b/llvm/test/ThinLTO/AArch64/cgdata-merge-read.ll
@@ -30,6 +30,20 @@
 ; RUN: llvm-objdump -d %tout-read.1 | FileCheck %s --check-prefix=THUNK1
 ; RUN: llvm-objdump -d %tout-read.2 | FileCheck %s --check-prefix=THUNK2
 
+; It runs the same if we use -indexed-codegen-data-read-function-map-names=false.
+; RUN: llvm-lto2 run -enable-global-merge-func=true \
+; RUN:    -indexed-codegen-data-read-function-map-names=false \
+; RUN:    -codegen-data-use-path=%tout.cgdata \
+; RUN:    %t-foo.bc %t-goo.bc -o %tout-read \
+; RUN:    -r %t-foo.bc,_f1,px \
+; RUN:    -r %t-goo.bc,_f2,px \
+; RUN:    -r %t-foo.bc,_g,l -r %t-foo.bc,_g1,l -r %t-foo.bc,_g2,l \
+; RUN:    -r %t-goo.bc,_g,l -r %t-goo.bc,_g1,l -r %t-goo.bc,_g2,l
+; RUN: llvm-nm %tout-read.1 | FileCheck %s --check-prefix=READ1
+; RUN: llvm-nm %tout-read.2 | FileCheck %s --check-prefix=READ2
+; RUN: llvm-objdump -d %tout-read.1 | FileCheck %s --check-prefix=THUNK1
+; RUN: llvm-objdump -d %tout-read.2 | FileCheck %s --check-prefix=THUNK2
+
 ; READ1: _f1.Tgm
 ; READ2: _f2.Tgm