[PATCH] D140237: [IR][NFC] Add BasicBlock::erase(Instruction *I) for erasing a single Instruction.

[Vasileios Porpodas via Phabricator via llvm-commits]

vporpo created this revision.
vporpo added reviewers: aeubanks, asbirlea.
Herald added a project: All.
vporpo requested review of this revision.
Herald added a project: LLVM.
Herald added a subscriber: llvm-commits.

Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D140237

Files:
  llvm/include/llvm/IR/BasicBlock.h
  llvm/unittests/IR/BasicBlockTest.cpp


Index: llvm/unittests/IR/BasicBlockTest.cpp
===================================================================
--- llvm/unittests/IR/BasicBlockTest.cpp
+++ llvm/unittests/IR/BasicBlockTest.cpp
@@ -541,5 +541,43 @@
   BB0->erase(BB0->begin(), BB0->end());
   EXPECT_TRUE(BB0->empty());
 }
+
+TEST(BasicBlockTest, EraseSingleInstr) {
+  LLVMContext Ctx;
+  std::unique_ptr<Module> M = parseIR(Ctx, R"(
+    define void @f(i32 %a) {
+     bb0:
+       %instr1 = add i32 %a, %a
+       %instr2 = sub i32 %a, %a
+       ret void
+    }
+)");
+  Function *F = &*M->begin();
+
+  auto BB0It = F->begin();
+  BasicBlock *BB0 = &*BB0It;
+
+  auto It = BB0->begin();
+  Instruction *Instr1 = &*It++;
+  Instruction *Instr2 = &*It++;
+  Instruction *Ret = &*It++;
+
+  EXPECT_EQ(BB0->size(), 3u);
+
+  // Erase %instr1
+  BB0->erase(Instr1);
+  EXPECT_EQ(BB0->size(), 2u);
+  EXPECT_EQ(&*BB0->begin(), Instr2);
+
+  // Erase ret
+  BB0->erase(Ret);
+  EXPECT_EQ(BB0->size(), 1u);
+  EXPECT_EQ(&*BB0->begin(), Instr2);
+
+  // Erase %instr2
+  BB0->erase(Instr2);
+  EXPECT_TRUE(BB0->empty());
+}
+
 } // End anonymous namespace.
 } // End llvm namespace.
Index: llvm/include/llvm/IR/BasicBlock.h
===================================================================
--- llvm/include/llvm/IR/BasicBlock.h
+++ llvm/include/llvm/IR/BasicBlock.h
@@ -490,6 +490,13 @@
   /// \Returns \p ToIt.
   BasicBlock::iterator erase(BasicBlock::iterator FromIt, BasicBlock::iterator ToIt);
 
+  /// Erases \p I from the instruction list. \Returns the iterator of the
+  /// instruction following \p I.
+  BasicBlock::iterator erase(Instruction *I) {
+    auto It = I->getIterator();
+    return erase(It, std::next(It));
+  }
+
   /// Returns true if there are any uses of this basic block other than
   /// direct branches, switches, etc. to it.
   bool hasAddressTaken() const {


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D140237.483610.patch
Type: text/x-patch
Size: 1854 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20221216/f0688389/attachment.bin>