From 014575932fc3acbb0f1c5b46ff2bfcebf69e6e62 Mon Sep 17 00:00:00 2001 From: Mehdi Amini Date: Sat, 27 Feb 2021 19:18:09 +0000 Subject: [PATCH] Fix Block::eraseArguments: keep track the first removed element while removing Not only this is likely more efficient than BitVector::find_first(), but also if the BitVector is empty find_first() returns -1, which llvm::drop_begin isn't robust against. --- mlir/lib/IR/Block.cpp | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/mlir/lib/IR/Block.cpp b/mlir/lib/IR/Block.cpp index 0758d1e..53797aa 100644 --- a/mlir/lib/IR/Block.cpp +++ b/mlir/lib/IR/Block.cpp @@ -192,15 +192,17 @@ void Block::eraseArguments(llvm::BitVector eraseIndices) { // We do this in reverse so that we erase later indices before earlier // indices, to avoid shifting the later indices. unsigned originalNumArgs = getNumArguments(); + int64_t firstErased = originalNumArgs; for (unsigned i = 0; i < originalNumArgs; ++i) { int64_t currentPos = originalNumArgs - i - 1; if (eraseIndices.test(currentPos)) { arguments[currentPos].destroy(); arguments.erase(arguments.begin() + currentPos); + firstErased = currentPos; } } // Update the cached position for the arguments after the first erased one. - int64_t index = eraseIndices.find_first(); + int64_t index = firstErased; for (BlockArgument arg : llvm::drop_begin(arguments, index)) arg.setArgNumber(index++); } -- 2.7.4