if entry == 0 {
			entry = pc
		}
		// Note that some platforms do ASLR, so the PCs in the disassembly
		// don't match PCs in the address space. Only offsets from function
		// entry make sense.
		unsafe := runtime.UnsafePoint(f.Entry() + uintptr(pc-entry))
		t.Logf("unsafe: %v\n", unsafe)
		instructionCount++
		if unsafe {
			unsafeCount++
		}

		// All the instructions inside the write barrier must be unpreemptible.