This is an arrow pointing up and left (or -45 degrees if up is 0 degrees). It's a basic line going from the bottom-right to the upper-left and then an arrowhead on that line continue to point to the upper-left.
This Up Left icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 6,100 icons, all in the same style and quality.