[llvm] 719ab04 - [GlobalISel] Handle IntToPtr constants in dbg.value

[Adrian Prantl via llvm-commits]

Author: Adrian Prantl
Date: 2022-07-27T13:42:07-07:00
New Revision: 719ab04acf97dde76249835b25ab3d246ff95877

URL: https://github.com/llvm/llvm-project/commit/719ab04acf97dde76249835b25ab3d246ff95877
DIFF: https://github.com/llvm/llvm-project/commit/719ab04acf97dde76249835b25ab3d246ff95877.diff

LOG: [GlobalISel] Handle IntToPtr constants in dbg.value

Currently, the IR to MIR translator can only handle two kinds of constant
inputs to dbg.values intrinsics: constant integers and constant floats. In
particular, it cannot handle pointers created from IntToPtr ConstantExpression
objects.

This patch addresses the limitation above by replacing the IntToPtr with
its input integer prior to converting the dbg.value input.

Patch by Felipe Piovezan!

Differential Revision: https://reviews.llvm.org/D130642

Added: 
    

Modified: 
    llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
    llvm/test/CodeGen/AArch64/GlobalISel/debug-insts.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp b/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
index 2e22dae35e5ad..4ecfda15d0323 100644
--- a/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
@@ -96,12 +96,20 @@ MachineInstrBuilder MachineIRBuilder::buildConstDbgValue(const Constant &C,
       cast<DILocalVariable>(Variable)->isValidLocationForIntrinsic(getDL()) &&
       "Expected inlined-at fields to agree");
   auto MIB = buildInstrNoInsert(TargetOpcode::DBG_VALUE);
-  if (auto *CI = dyn_cast<ConstantInt>(&C)) {
+
+  auto *NumericConstant = [&] {
+    if (const auto *CE = dyn_cast<ConstantExpr>(&C))
+      if (CE->getOpcode() == Instruction::IntToPtr)
+        return cast<const Constant>(CE->getOperand(0));
+    return &C;
+  }();
+
+  if (auto *CI = dyn_cast<ConstantInt>(NumericConstant)) {
     if (CI->getBitWidth() > 64)
       MIB.addCImm(CI);
     else
       MIB.addImm(CI->getZExtValue());
-  } else if (auto *CFP = dyn_cast<ConstantFP>(&C)) {
+  } else if (auto *CFP = dyn_cast<ConstantFP>(NumericConstant)) {
     MIB.addFPImm(CFP);
   } else {
     // Insert $noreg if we didn't find a usable constant and had to drop it.

diff  --git a/llvm/test/CodeGen/AArch64/GlobalISel/debug-insts.ll b/llvm/test/CodeGen/AArch64/GlobalISel/debug-insts.ll
index 7ace28ebe9481..5573378b087da 100644
--- a/llvm/test/CodeGen/AArch64/GlobalISel/debug-insts.ll
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/debug-insts.ll
@@ -40,6 +40,8 @@ define void @debug_value(i32 %in) #0 !dbg !16 {
   call void @llvm.dbg.value(metadata float 1.000000e+00, i64 0, metadata !17, metadata !DIExpression()), !dbg !18
 ; CHECK: DBG_VALUE $noreg, 0, !17, !DIExpression(), debug-location !18
   call void @llvm.dbg.value(metadata i32* null, i64 0, metadata !17, metadata !DIExpression()), !dbg !18
+; CHECK: DBG_VALUE 42, 0, !17, !DIExpression(), debug-location !18
+  call void @llvm.dbg.value(metadata i32* inttoptr (i64 42 to i32*), i64 0, metadata !17, metadata !DIExpression()), !dbg !18
   ret void
 }