HIR stands for High Level Intermediate Representation. In JRockit, this is what the bytecode first turns into, when generating native code from bytecode. JRockit HIR is a directed control flow graph with basic blocks as nodes. Each basic block contains zero or more operations, which in turn may use other operations as operands. JRockit HIR is, like Java, completely platform-independent.

See also MIR, LIR, IR, Register allocation, and Native code.