[RemoveDIs] Handle DPValues in LowerDbgDeclare (#73504)

The tests will become "live" once #74090 lands (see for more info).

Author: OCHyams

llvm/lib/Transforms/Utils/Local.cpp

@@ -1724,16 +1724,19 @@ void llvm::ConvertDebugDeclareToDebugValue(DbgVariableIntrinsic *DII,
                           SI->getIterator());
 }
 
+namespace llvm {
 // RemoveDIs: duplicate the getDebugValueLoc method using DPValues instead of
-// dbg.value intrinsics.
-static DebugLoc getDebugValueLocDPV(DPValue *DPV) {
+// dbg.value intrinsics. In llvm namespace so that it overloads the
+// DbgVariableIntrinsic version.
+static DebugLoc getDebugValueLoc(DPValue *DPV) {
   // Original dbg.declare must have a location.
   const DebugLoc &DeclareLoc = DPV->getDebugLoc();
   MDNode *Scope = DeclareLoc.getScope();
   DILocation *InlinedAt = DeclareLoc.getInlinedAt();
   // Produce an unknown location with the correct scope / inlinedAt fields.
   return DILocation::get(DPV->getContext(), 0, 0, Scope, InlinedAt);
 }
+} // namespace llvm
 
 /// Inserts a llvm.dbg.value intrinsic before a load of an alloca'd value
 /// that has an associated llvm.dbg.declare intrinsic.
@@ -1770,7 +1773,7 @@ void llvm::ConvertDebugDeclareToDebugValue(DPValue *DPV, StoreInst *SI,
   auto *DIExpr = DPV->getExpression();
   Value *DV = SI->getValueOperand();
 
-  DebugLoc NewLoc = getDebugValueLocDPV(DPV);
+  DebugLoc NewLoc = getDebugValueLoc(DPV);
 
   if (!valueCoversEntireFragment(DV->getType(), DPV)) {
     // FIXME: If storing to a part of the variable described by the dbg.declare,
@@ -1842,7 +1845,7 @@ void llvm::ConvertDebugDeclareToDebugValue(DPValue *DPV, LoadInst *LI,
     return;
   }
 
-  DebugLoc NewLoc = getDebugValueLocDPV(DPV);
+  DebugLoc NewLoc = getDebugValueLoc(DPV);
 
   // We are now tracking the loaded value instead of the address. In the
   // future if multi-location support is added to the IR, it might be
@@ -1887,7 +1890,7 @@ void llvm::ConvertDebugDeclareToDebugValue(DPValue *DPV, PHINode *APN,
   BasicBlock *BB = APN->getParent();
   auto InsertionPt = BB->getFirstInsertionPt();
 
-  DebugLoc NewLoc = getDebugValueLocDPV(DPV);
+  DebugLoc NewLoc = getDebugValueLoc(DPV);
 
   // The block may be a catchswitch block, which does not have a valid
   // insertion point.
@@ -1903,25 +1906,32 @@ bool llvm::LowerDbgDeclare(Function &F) {
   bool Changed = false;
   DIBuilder DIB(*F.getParent(), /*AllowUnresolved*/ false);
   SmallVector<DbgDeclareInst *, 4> Dbgs;
-  for (auto &FI : F)
-    for (Instruction &BI : FI)
-      if (auto DDI = dyn_cast<DbgDeclareInst>(&BI))
+  SmallVector<DPValue *> DPVs;
+  for (auto &FI : F) {
+    for (Instruction &BI : FI) {
+      if (auto *DDI = dyn_cast<DbgDeclareInst>(&BI))
         Dbgs.push_back(DDI);
+      for (DPValue &DPV : BI.getDbgValueRange()) {
+        if (DPV.getType() == DPValue::LocationType::Declare)
+          DPVs.push_back(&DPV);
+      }
+    }
+  }
 
-  if (Dbgs.empty())
+  if (Dbgs.empty() && DPVs.empty())
     return Changed;
 
-  for (auto &I : Dbgs) {
-    DbgDeclareInst *DDI = I;
-    AllocaInst *AI = dyn_cast_or_null<AllocaInst>(DDI->getAddress());
+  auto LowerOne = [&](auto *DDI) {
+    AllocaInst *AI =
+        dyn_cast_or_null<AllocaInst>(DDI->getVariableLocationOp(0));
     // If this is an alloca for a scalar variable, insert a dbg.value
     // at each load and store to the alloca and erase the dbg.declare.
     // The dbg.values allow tracking a variable even if it is not
     // stored on the stack, while the dbg.declare can only describe
     // the stack slot (and at a lexical-scope granularity). Later
     // passes will attempt to elide the stack slot.
     if (!AI || isArray(AI) || isStructure(AI))
-      continue;
+      return;
 
     // A volatile load/store means that the alloca can't be elided anyway.
     if (llvm::any_of(AI->users(), [](User *U) -> bool {
@@ -1931,7 +1941,7 @@ bool llvm::LowerDbgDeclare(Function &F) {
             return SI->isVolatile();
           return false;
         }))
-      continue;
+      return;
 
     SmallVector<const Value *, 8> WorkList;
     WorkList.push_back(AI);
@@ -1963,11 +1973,14 @@ bool llvm::LowerDbgDeclare(Function &F) {
     }
     DDI->eraseFromParent();
     Changed = true;
-  }
+  };
+
+  for_each(Dbgs, LowerOne);
+  for_each(DPVs, LowerOne);
 
   if (Changed)
-  for (BasicBlock &BB : F)
-    RemoveRedundantDbgInstrs(&BB);
+    for (BasicBlock &BB : F)
+      RemoveRedundantDbgInstrs(&BB);
 
   return Changed;
 }

llvm/test/DebugInfo/ARM/lowerbdgdeclare_vla.ll

@@ -1,4 +1,5 @@
 ; RUN: opt  -passes=instcombine %s -S | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators  -passes=instcombine %s -S | FileCheck %s
 ;
 ; Generate me from:
 ; clang -cc1 -triple thumbv7-apple-ios7.0.0 -S -target-abi apcs-gnu -gdwarf-2 -Os test.c -o test.ll -emit-llvm

llvm/test/DebugInfo/Generic/dbg-value-lower-linenos.ll

@@ -1,4 +1,5 @@
 ; RUN: opt < %s -S -passes=mem2reg,instcombine | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators < %s -S -passes=mem2reg,instcombine | FileCheck %s
 
 ; The '%bar' alloca will be promoted to an SSA register by mem2reg: test that
 ; zero line number are assigned to the dbg.value intrinsics that are inserted

llvm/test/DebugInfo/X86/array2.ll

@@ -13,6 +13,7 @@
 ; }
 ;
 ; RUN: opt %s -O2 -S -o - | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators %s -O2 -S -o - | FileCheck %s
 ; Test that we correctly lower dbg.declares for arrays.
 ;
 ; CHECK: define i32 @main

llvm/test/DebugInfo/X86/formal_parameter.ll

@@ -15,6 +15,7 @@ target triple = "x86_64-apple-macosx10.9.0"
 ; RUN: opt %s -O2 -S -o %t
 ; RUN: cat %t | FileCheck --check-prefix=LOWERING %s
 ; RUN: llc -filetype=obj %t -o - | llvm-dwarfdump -debug-info - | FileCheck %s
+; RUN: llc --try-experimental-debuginfo-iterators -filetype=obj %t -o - | llvm-dwarfdump -debug-info - | FileCheck %s
 ; Test that we only emit only one DW_AT_formal_parameter "map" for this function.
 ; rdar://problem/14874886
 ;

llvm/test/DebugInfo/X86/instcombine-instrinsics.ll

@@ -1,4 +1,5 @@
 ; RUN: opt %s -O2 -S -o - | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators %s -O2 -S -o - | FileCheck %s
 ; Verify that we emit the same intrinsic at most once.
 ; rdar://problem/13056109
 ;

llvm/test/DebugInfo/duplicate_dbgvalue.ll

@@ -1,4 +1,5 @@
 ; RUN: opt -passes=instcombine -S -o - < %s | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators -passes=instcombine -S -o - < %s | FileCheck %s
 
 ; CHECK-LABEL: %3 = load i32, ptr %i1_311
 ; CHECK: call void @llvm.dbg.value(metadata i32 %3

llvm/test/DebugInfo/verify-di-preserve.ll

@@ -1,8 +1,10 @@
 ; RUN: opt %s -verify-debuginfo-preserve -passes=instcombine -disable-output 2>&1 | FileCheck --check-prefix=VERIFY %s
+; RUN: opt --try-experimental-debuginfo-iterators %s -verify-debuginfo-preserve -passes=instcombine -disable-output 2>&1 | FileCheck --check-prefix=VERIFY %s
 
 ; VERIFY: CheckModuleDebugify (original debuginfo):
 
 ; RUN: opt %s -verify-each-debuginfo-preserve -O2 -disable-output 2>&1 | FileCheck --check-prefix=VERIFY-EACH %s
+; RUN: opt %s  --try-experimental-debuginfo-iterators -verify-each-debuginfo-preserve -O2 -disable-output 2>&1 | FileCheck --check-prefix=VERIFY-EACH %s
 
 ; VERIFY-EACH: DeadArgumentEliminationPass
 ; VERIFY-EACH: GlobalDCEPass

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

@@ -2,6 +2,7 @@
 ; RUN: opt < %s -passes='instcombine' -S | FileCheck %s
 ; RUN: opt < %s -passes='instcombine' -S --try-experimental-debuginfo-iterators | FileCheck %s
 
+
 define i32 @foo(<vscale x 2 x i32> %x) {
 ; CHECK-LABEL: @foo(
 ; CHECK-NEXT:  entry:

llvm/test/Transforms/InstCombine/dbg-simplify-alloca-size.ll

@@ -1,4 +1,5 @@
 ; RUN: opt -S --passes=instcombine %s | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators -S --passes=instcombine %s | FileCheck %s
 
 ; https://github.com/llvm/llvm-project/issues/56807
 declare void @foo(ptr %pixels)

llvm/test/Transforms/InstCombine/debuginfo-scalable-typesize.ll

@@ -1,4 +1,5 @@
 ; RUN: opt -passes=instcombine -S < %s | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators -passes=instcombine -S < %s | FileCheck %s
 
 ; This test is defending against a TypeSize message raised in the method
 ; `valueCoversEntireFragment` in Local.cpp because of an implicit cast from

llvm/test/Transforms/InstCombine/lifetime-no-null-opt.ll

@@ -1,5 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators < %s -passes=instcombine -S | FileCheck %s
 
 declare void @llvm.dbg.declare(metadata, metadata, metadata)
 declare void @llvm.lifetime.start.p0(i64, ptr nocapture)

llvm/test/Transforms/InstCombine/lifetime.ll

@@ -1,5 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+; RUN: opt --try-experimental-debuginfo-iterators < %s -passes=instcombine -S | FileCheck %s
 
 declare void @llvm.dbg.declare(metadata, metadata, metadata)
 declare void @llvm.lifetime.start.p0(i64, ptr nocapture)