[InstCombine][debuginfo] Update valueCoversEntireFragment for fixed size fragment and scalable value.

Update valueCoversEntireFragment to handle new case and add regression test.

Reviewed By: sdesmalen, aprantl

Differential Revision: https://reviews.llvm.org/D144472

Author: Yeting Kuo

llvm/lib/Transforms/Utils/Local.cpp

@@ -1493,11 +1493,9 @@ static bool PhiHasDebugValue(DILocalVariable *DIVar,
 static bool valueCoversEntireFragment(Type *ValTy, DbgVariableIntrinsic *DII) {
   const DataLayout &DL = DII->getModule()->getDataLayout();
   TypeSize ValueSize = DL.getTypeAllocSizeInBits(ValTy);
-  if (std::optional<uint64_t> FragmentSize = DII->getFragmentSizeInBits()) {
-    assert(!ValueSize.isScalable() &&
-           "Fragments don't work on scalable types.");
-    return ValueSize.getFixedValue() >= *FragmentSize;
-  }
+  if (std::optional<uint64_t> FragmentSize = DII->getFragmentSizeInBits())
+    return TypeSize::isKnownGE(ValueSize, TypeSize::getFixed(*FragmentSize));
+
   // We can't always calculate the size of the DI variable (e.g. if it is a
   // VLA). Try to use the size of the alloca that the dbg intrinsic describes
   // intead.

llvm/test/Transforms/InstCombine/dbg-scalable-store-fixed-frag.ll

@@ -0,0 +1,63 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -passes='instcombine' -S | FileCheck %s
+
+define i32 @foo(<vscale x 2 x i32> %x) {
+; CHECK-LABEL: @foo(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[ARR:%.*]] = alloca i32, align 8
+; CHECK-NEXT:    call void @llvm.dbg.value(metadata <vscale x 2 x i32> undef, metadata [[META8:![0-9]+]], metadata !DIExpression()), !dbg [[DBG14:![0-9]+]]
+; CHECK-NEXT:    store <vscale x 2 x i32> [[X:%.*]], ptr [[ARR]], align 8
+; CHECK-NEXT:    [[RES:%.*]] = load i32, ptr [[ARR]], align 8
+; CHECK-NEXT:    ret i32 [[RES]]
+;
+entry:
+  %arr = alloca i32, align 4
+  call void @llvm.dbg.declare(metadata ptr %arr, metadata !8, metadata !DIExpression()), !dbg !14
+  store <vscale x 2 x i32> %x, ptr %arr, align 4
+  %res = load i32, ptr %arr
+  ret i32 %res
+}
+
+define i32 @foo2(<vscale x 2 x i32> %x) {
+; CHECK-LABEL: @foo2(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[ARR:%.*]] = alloca [4 x i32], align 8
+; CHECK-NEXT:    call void @llvm.dbg.declare(metadata ptr [[ARR]], metadata [[META15:![0-9]+]], metadata !DIExpression()), !dbg [[DBG17:![0-9]+]]
+; CHECK-NEXT:    store <vscale x 2 x i32> [[X:%.*]], ptr [[ARR]], align 8
+; CHECK-NEXT:    [[RES:%.*]] = load i32, ptr [[ARR]], align 8
+; CHECK-NEXT:    ret i32 [[RES]]
+;
+entry:
+  %arr = alloca [4 x i32], align 4
+  call void @llvm.dbg.declare(metadata ptr %arr, metadata !15, metadata !DIExpression()), !dbg !17
+  store <vscale x 2 x i32> %x, ptr %arr, align 4
+  %res = load i32, ptr %arr
+  ret i32 %res
+}
+
+; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #0
+
+attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4, !5, !6, !7}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 17.0.0 ([email protected]:llvm/llvm-project.git a489e11439e36c7e0ec83b28a6fb1596a5c21faa)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, retainedTypes: !2, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: "u.cpp", directory: "/path/to/test", checksumkind: CSK_MD5, checksum: "42f62c17fb0f0110f515890bc6d69cb5")
+!2 = !{}
+!3 = !{i32 7, !"Dwarf Version", i32 5}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{i32 1, !"wchar_size", i32 4}
+!6 = !{i32 1, !"target-abi", !"lp64d"}
+!7 = !{i32 8, !"SmallDataLimit", i32 8}
+!8 = !DILocalVariable(name: "arr", scope: !9, file: !1, line: 3, type: !12)
+!9 = distinct !DISubprogram(name: "foo", linkageName: "foo", scope: !1, file: !1, line: 2, type: !10, scopeLine: 2, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2)
+!10 = !DISubroutineType(types: !11)
+!11 = !{null}
+!12 = !DICompositeType(tag: DW_TAG_array_type, baseType: !13, size: 128, elements: !2)
+!13 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!14 = !DILocation(line: 3, column: 7, scope: !9)
+!15 = !DILocalVariable(name: "arr", scope: !16, file: !1, line: 6, type: !12)
+!16 = distinct !DISubprogram(name: "foo2", linkageName: "foo2", scope: !1, file: !1, line: 5, type: !10, scopeLine: 5, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2)
+!17 = !DILocation(line: 6, column: 7, scope: !16)