[llvm] LowerTypeTests: Stop creating inline bitset tests on 32-bit architectures. (PR #143458)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-transforms

Author: Peter Collingbourne (pcc)

<details>
<summary>Changes</summary>

Tests with a 64-bit inline bitset are not only unlikely to be beneficial
on 32-bit architectures but with ThinLTO we are unable to export them
correctly, resulting in a miscompile.


---
Full diff: https://github.com/llvm/llvm-project/pull/143458.diff


2 Files Affected:

- (modified) llvm/lib/Transforms/IPO/LowerTypeTests.cpp (+1-1) 
- (modified) llvm/test/Transforms/LowerTypeTests/export-inline.ll (+18-9) 


``````````diff
diff --git a/llvm/lib/Transforms/IPO/LowerTypeTests.cpp b/llvm/lib/Transforms/IPO/LowerTypeTests.cpp
index 8d8a73729e74c..ab67a0980e0c2 100644
--- a/llvm/lib/Transforms/IPO/LowerTypeTests.cpp
+++ b/llvm/lib/Transforms/IPO/LowerTypeTests.cpp
@@ -1173,7 +1173,7 @@ void LowerTypeTestsModule::lowerTypeTestCalls(
     if (BSI.isAllOnes()) {
       TIL.TheKind = (BSI.BitSize == 1) ? TypeTestResolution::Single
                                        : TypeTestResolution::AllOnes;
-    } else if (BSI.BitSize <= 64) {
+    } else if (BSI.BitSize <= IntPtrTy->getBitWidth()) {
       TIL.TheKind = TypeTestResolution::Inline;
       uint64_t InlineBits = 0;
       for (auto Bit : BSI.Bits)
diff --git a/llvm/test/Transforms/LowerTypeTests/export-inline.ll b/llvm/test/Transforms/LowerTypeTests/export-inline.ll
index 956f0e3bfbbf1..aaaa0ee144e2e 100644
--- a/llvm/test/Transforms/LowerTypeTests/export-inline.ll
+++ b/llvm/test/Transforms/LowerTypeTests/export-inline.ll
@@ -1,8 +1,11 @@
-; RUN: opt -mtriple=x86_64-unknown-linux -S -passes=lowertypetests -lowertypetests-summary-action=export -lowertypetests-read-summary=%S/Inputs/use-typeid1-typeid2.yaml -lowertypetests-write-summary=%t %s | FileCheck --check-prefix=CHECK %s
-; RUN: FileCheck --check-prefixes=SUMMARY,SUMMARY-X86 %s < %t
+; RUN: opt -mtriple=i686-unknown-linux -S -passes=lowertypetests -lowertypetests-summary-action=export -lowertypetests-read-summary=%S/Inputs/use-typeid1-typeid2.yaml -lowertypetests-write-summary=%t %s | FileCheck --check-prefixes=CHECK,CHECK-X86-32 %s
+; RUN: FileCheck --check-prefixes=SUMMARY,SUMMARY-X86,SUMMARY-X86-32 %s < %t
 
-; RUN: opt -mtriple=aarch64-unknown-linux -S -passes=lowertypetests -lowertypetests-summary-action=export -lowertypetests-read-summary=%S/Inputs/use-typeid1-typeid2.yaml -lowertypetests-write-summary=%t %s | FileCheck --check-prefix=CHECK %s
-; RUN: FileCheck --check-prefixes=SUMMARY,SUMMARY-ARM %s < %t
+; RUN: opt -mtriple=x86_64-unknown-linux -S -passes=lowertypetests -lowertypetests-summary-action=export -lowertypetests-read-summary=%S/Inputs/use-typeid1-typeid2.yaml -lowertypetests-write-summary=%t %s | FileCheck --check-prefixes=CHECK,CHECK-64 %s
+; RUN: FileCheck --check-prefixes=SUMMARY,SUMMARY-X86,SUMMARY-64 %s < %t
+
+; RUN: opt -mtriple=aarch64-unknown-linux -S -passes=lowertypetests -lowertypetests-summary-action=export -lowertypetests-read-summary=%S/Inputs/use-typeid1-typeid2.yaml -lowertypetests-write-summary=%t %s | FileCheck --check-prefixes=CHECK,CHECK-64 %s
+; RUN: FileCheck --check-prefixes=SUMMARY,SUMMARY-64,SUMMARY-ARM %s < %t
 
 @foo = constant [2048 x i8] zeroinitializer, !type !0, !type !1, !type !2, !type !3
 
@@ -13,15 +16,19 @@
 
 ; CHECK: [[G:@[0-9]+]] = private constant { [2048 x i8] } zeroinitializer
 
-; CHECK: @__typeid_typeid1_global_addr = hidden alias i8, getelementptr (i8, ptr [[G]], i64 6)
+; CHECK-X86-32: @__typeid_typeid1_global_addr = hidden alias i8, getelementptr (i8, ptr [[G]], i32 6)
+; CHECK-64: @__typeid_typeid1_global_addr = hidden alias i8, getelementptr (i8, ptr [[G]], i64 6)
 ; CHECK-X86: @__typeid_typeid1_align = hidden alias i8, inttoptr (i8 1 to ptr)
 ; CHECK-X86: @__typeid_typeid1_size_m1 = hidden alias i8, inttoptr (i64 3 to ptr)
 ; CHECK-X86: @__typeid_typeid1_inline_bits = hidden alias i8, inttoptr (i32 9 to ptr)
 
-; CHECK: @__typeid_typeid2_global_addr = hidden alias i8, getelementptr (i8, ptr [[G]], i64 136)
+; CHECK-X86-32: @__typeid_typeid2_global_addr = hidden alias i8, getelementptr (i8, ptr [[G]], i32 136)
+; CHECK-64: @__typeid_typeid2_global_addr = hidden alias i8, getelementptr (i8, ptr [[G]], i64 136)
 ; CHECK-X86: @__typeid_typeid2_align = hidden alias i8, inttoptr (i8 2 to ptr)
 ; CHECK-X86: @__typeid_typeid2_size_m1 = hidden alias i8, inttoptr (i64 33 to ptr)
-; CHECK-X86: @__typeid_typeid2_inline_bits = hidden alias i8, inttoptr (i64 8589934593 to ptr)
+; CHECK-X86-64: @__typeid_typeid2_inline_bits = hidden alias i8, inttoptr (i64 8589934593 to ptr)
+; CHECK-X86-32: @__typeid_typeid2_byte_array = hidden alias i8, ptr @bits
+; CHECK-X86-32: @__typeid_typeid2_bit_mask = hidden alias i8, inttoptr (i8 1 to ptr)
 
 ; CHECK: @foo = alias [2048 x i8], ptr [[G]]
 
@@ -41,8 +48,10 @@
 ; SUMMARY-NEXT:     WPDRes:
 ; SUMMARY-NEXT:   typeid2:
 ; SUMMARY-NEXT:     TTRes:
-; SUMMARY-NEXT:       Kind:            Inline
-; SUMMARY-NEXT:       SizeM1BitWidth:  6
+; SUMMARY-X86-32-NEXT: Kind:           ByteArray
+; SUMMARY-X86-32-NEXT: SizeM1BitWidth: 7
+; SUMMARY-64-NEXT:    Kind:            Inline
+; SUMMARY-64-NEXT:    SizeM1BitWidth:  6
 ; SUMMARY-X86-NEXT:   AlignLog2:       0
 ; SUMMARY-X86-NEXT:   SizeM1:          0
 ; SUMMARY-X86-NEXT:   BitMask:         0

``````````

</details>


https://github.com/llvm/llvm-project/pull/143458