commit 90d856cd5f4c4bfe415105f6bfc66f05457a334d
author Wolfgang Pieb <Wolfgang.Pieb@sony.com> Mon Feb 04 20:42:45 2019 +0000
committer Wolfgang Pieb <Wolfgang.Pieb@sony.com> Mon Feb 04 20:42:45 2019 +0000
tree 22d5f7196beed92b2db40456b05d30d86d00ed99
parent 690a20467b6684edb49f6f23a594e4649e8626a6

[DEBUGINFO] Reposting r352642: Handle restore instructions in LiveDebugValues

The LiveDebugValues pass recognizes spills but not restores, which can
cause large gaps in location information for some variables, depending
on control flow. This patch make LiveDebugValues recognize restores and
generate appropriate DBG_VALUE instructions.

This patch was posted previously with r352642 and reverted in r352666 due
to buildbot errors. A missing return statement was the cause for the 
failures.

Reviewers: aprantl, NicolaPrica

Differential Revision: https://reviews.llvm.org/D57271

llvm-svn: 353089

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index b8d4466..be666ad 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -746,41 +746,20 @@
   const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
 
   // Check for spills and reloads
-  int FI;
-
-  const MachineFrameInfo &MFI = MF->getFrameInfo();
-
-  auto getSize =
-      [&MFI](const SmallVectorImpl<const MachineMemOperand *> &Accesses) {
-        unsigned Size = 0;
-        for (auto A : Accesses)
-          if (MFI.isSpillSlotObjectIndex(
-                  cast<FixedStackPseudoSourceValue>(A->getPseudoValue())
-                      ->getFrameIndex()))
-            Size += A->getSize();
-        return Size;
-      };
 
   // We assume a single instruction only has a spill or reload, not
   // both.
-  const MachineMemOperand *MMO;
-  SmallVector<const MachineMemOperand *, 2> Accesses;
-  if (TII->isLoadFromStackSlotPostFE(MI, FI)) {
-    if (MFI.isSpillSlotObjectIndex(FI)) {
-      MMO = *MI.memoperands_begin();
-      CommentOS << MMO->getSize() << "-byte Reload\n";
-    }
-  } else if (TII->hasLoadFromStackSlot(MI, Accesses)) {
-    if (auto Size = getSize(Accesses))
-      CommentOS << Size << "-byte Folded Reload\n";
-  } else if (TII->isStoreToStackSlotPostFE(MI, FI)) {
-    if (MFI.isSpillSlotObjectIndex(FI)) {
-      MMO = *MI.memoperands_begin();
-      CommentOS << MMO->getSize() << "-byte Spill\n";
-    }
-  } else if (TII->hasStoreToStackSlot(MI, Accesses)) {
-    if (auto Size = getSize(Accesses))
-      CommentOS << Size << "-byte Folded Spill\n";
+  Optional<unsigned> Size;
+  if ((Size = MI.getRestoreSize(TII))) {
+    CommentOS << *Size << "-byte Reload\n";
+  } else if ((Size = MI.getFoldedRestoreSize(TII))) {
+    if (*Size)
+      CommentOS << *Size << "-byte Folded Reload\n";
+  } else if ((Size = MI.getSpillSize(TII))) {
+    CommentOS << *Size << "-byte Spill\n";
+  } else if ((Size = MI.getFoldedSpillSize(TII))) {
+    if (*Size)
+      CommentOS << *Size << "-byte Folded Spill\n";
   }
 
   // Check for spill-induced copies