Factor emulation routines into multiple files

1 files changed, 67 insertions, 0 deletions

diff --git a/machine/fp_ldst.c b/machine/fp_ldst.c
new file mode 100644
index 0000000..9d0a49f
--- /dev/null
+++ b/machine/fp_ldst.c
@@ -0,0 +1,67 @@
+#include "fp_emulation.h"
+#include "unprivileged_memory.h"
+
+DECLARE_EMULATION_FUNC(emulate_float_load)
+{
+  uint64_t val;
+  uintptr_t addr = GET_RS1(insn, regs) + IMM_I(insn);
+  
+  switch (insn & MASK_FUNCT3)
+  {
+    case MATCH_FLW & MASK_FUNCT3:
+      if (addr % 4 != 0)
+        return misaligned_load_trap(regs, mcause, mepc);
+
+      SET_F32_RD(insn, regs, load_int32_t((void *)addr, mepc));
+      break;
+
+    case MATCH_FLD & MASK_FUNCT3:
+      if (addr % sizeof(uintptr_t) != 0)
+        return misaligned_load_trap(regs, mcause, mepc);
+
+#ifdef __riscv64
+      val = load_uint64_t((void *)addr, mepc);
+#else
+      val = load_uint32_t(addr, mepc);
+      val += (uint64_t)load_uint32_t((void *)(addr + 4), mepc) << 32;
+#endif
+      SET_F64_RD(insn, regs, val);
+      break;
+
+    default:
+      return truly_illegal_insn(regs, mcause, mepc, mstatus, insn);
+  }
+}
+
+DECLARE_EMULATION_FUNC(emulate_float_store)
+{
+  uint64_t val;
+  uintptr_t addr = GET_RS1(insn, regs) + IMM_S(insn);
+  
+  switch (insn & MASK_FUNCT3)
+  {
+    case MATCH_FSW & MASK_FUNCT3:
+      if (addr % 4 != 0)
+        return misaligned_store_trap(regs, mcause, mepc);
+
+      store_uint32_t((void *)addr, GET_F32_RS2(insn, regs), mepc);
+      break;
+
+    case MATCH_FSD & MASK_FUNCT3:
+      if (addr % sizeof(uintptr_t) != 0)
+        return misaligned_store_trap(regs, mcause, mepc);
+
+      val = GET_F64_RS2(insn, regs);
+#ifdef __riscv64
+      store_uint64_t((void *)addr, val, mepc);
+#else
+      store_uint32_t((void *)addr, val, mepc);
+      store_uint32_t((void *)(addr + 4), val >> 32, mepc);
+#endif
+      break;
+
+    default:
+      return truly_illegal_insn(regs, mcause, mepc, mstatus, insn);
+  }
+}
+