Merge branch 'feature/riscv-linker'

Makefile

@@ -62,7 +62,7 @@ endif
 # CFLAGS+=-DNDEBUG
 
 UNAME:=$(shell uname)
-ifeq ("$(UNAME)", "Darwin")
+ifeq ("$(UNAME):$(HOST_CC_PREFIX)", "Darwin:")
 LIBS:=
 else
 LIBS:=$(LIB_DIR)/crt0.a $(LIB_DIR)/libc.a
@@ -167,7 +167,7 @@ ifeq ("$(LIBS)", "")
 libs: exes
 else
 libs: exes
-	$(MAKE) CC=../xcc -C libsrc
+	$(MAKE) CC=../xcc HOST_CC_PREFIX=$(HOST_CC_PREFIX) -C libsrc
 endif
 
 ### Self hosting

include/setjmp.h

@@ -10,6 +10,9 @@ typedef uintptr_t jmp_buf[192 / 8];
 
 #elif defined(__x86_64__)
 typedef uintptr_t jmp_buf[200 / 8];  // GCC
+
+#elif defined(__riscv)
+typedef uintptr_t jmp_buf[208 / 8];
 #endif
 
 int setjmp(jmp_buf env);

libsrc/Makefile

@@ -13,6 +13,10 @@ else
 CFLAGS:=-I$(INC_DIR) -Wall -Wextra -Werror
 endif
 
+ifneq ("$(HOST_CC_PREFIX)", "")
+  AR:=$(HOST_CC_PREFIX)ar
+endif
+
 ### Library
 
 CRT0_DIR:=$(SRC_DIR)/crt0

libsrc/crt0/_start.c

@@ -45,6 +45,13 @@ void _start(void) {
         "mov x1, x2\n"
         "mov x2, x3\n"
         "b start2");
+#elif defined(__riscv)
+  __asm("lw a0, 0(sp)\n"  // argc
+        "addi a1, sp, 8\n"  // argv
+        "slli a2, a0, 3\n"
+        "addi a2, a2, 8\n"
+        "add  a2, a2, a1\n"  // envp
+        "j start2\n");
 #else
 #error unknown target
 #endif

libsrc/misc/longjmp.c

@@ -49,5 +49,26 @@ void longjmp(jmp_buf env, int result) {
         "mov w0, #1\n"
         ".longjmp_0:");
 }
+#elif defined(__riscv)
+void longjmp(jmp_buf env, int result) {
+  __asm("ld ra, 0(a0)\n"
+        "ld sp, 8(a0)\n"
+        "ld fp, 16(a0)\n"
+        "ld s1, 24(a0)\n"
+        "ld s2, 32(a0)\n"
+        "ld s3, 40(a0)\n"
+        "ld s4, 48(a0)\n"
+        "ld s5, 56(a0)\n"
+        "ld s6, 64(a0)\n"
+        "ld s7, 72(a0)\n"
+        "ld s8, 80(a0)\n"
+        "ld s9, 88(a0)\n"
+        "ld s10, 96(a0)\n"
+        "ld s11, 104(a0)\n"
+        "mv a0, a1\n"
+        "bne a0, zero, .longjmp_0\n"
+        "li a0, 1\n"
+        ".longjmp_0:");
+}
 #endif
 #endif

libsrc/misc/setjmp.c

@@ -41,5 +41,23 @@ int setjmp(jmp_buf env) {
         "stp d14, d15, [x0, 160]\n"
         "mov w0, wzr");
 }
+#elif defined(__riscv)
+int setjmp(jmp_buf env) {
+  __asm("sd ra, 0(a0)\n"
+        "sd sp, 8(a0)\n"
+        "sd fp, 16(a0)\n"
+        "sd s1, 24(a0)\n"
+        "sd s2, 32(a0)\n"
+        "sd s3, 40(a0)\n"
+        "sd s4, 48(a0)\n"
+        "sd s5, 56(a0)\n"
+        "sd s6, 64(a0)\n"
+        "sd s7, 72(a0)\n"
+        "sd s8, 80(a0)\n"
+        "sd s9, 88(a0)\n"
+        "sd s10, 96(a0)\n"
+        "sd s11, 104(a0)\n"
+        "li a0, 0\n");
+}
 #endif
 #endif

libsrc/stdio/stdin.c

@@ -9,8 +9,21 @@
 static FILE _stdin = {.iof = IOF, .flush = _fflush, .fd = STDIN_FILENO, .flag = FF_READ};
 static FILE _stdout = {.iof = IOF, .flush = _fflush, .fd = STDOUT_FILENO, .flag = FF_WRITE, .wbuf = _stdout.wwork, .ws = sizeof(_stdout.wwork)};
 static FILE _stderr = {.iof = IOF, .flush = _fflush, .fd = STDERR_FILENO, .flag = FF_WRITE, .wbuf = _stderr.wwork, .ws = sizeof(_stderr.wwork)};
+
+#if defined(__riscv)
+static struct _reent _impure_entity = {
+  ._errno = 0,
+  ._stdin = &_stdin,
+  ._stdout = &_stdout,
+  ._stderr = &_stderr,
+};
+struct _reent *_impure_ptr = &_impure_entity;
+
+#else
+
 FILE *stdin = &_stdin;
 FILE *stdout = &_stdout;
 FILE *stderr = &_stderr;
+#endif
 
 FILEMAN __fileman;

libsrc/unistd/_syscall.h

@@ -76,6 +76,34 @@
 #define __NR_clock_gettime  113
 #define __NR_newfstatat  79
 
+#elif defined(__riscv)
+
+#define SYSCALL(no)  _SYSCALL2(no)
+#define _SYSCALL2(no) \
+    __asm("li a7, " #no "\n" \
+          "ecall")
+
+#define SYSCALL_RET(no, ret)  _SYSCALL_RET2(no, ret)
+#define _SYSCALL_RET2(no, ret) \
+    __asm("li a7, " #no "\n" \
+          "ecall" \
+          : "=r"(ret))
+
+#define __NR_getcwd  17
+#define __NR_dup     23
+#define __NR_chdir   49
+#define __NR_openat  56
+#define __NR_close   57
+#define __NR_lseek   62
+#define __NR_read    63
+#define __NR_write   64
+#define __NR_exit    93
+#define __NR_kill    129
+#define __NR_brk     214
+#define __NR_execve  221
+#define __NR_wait4   260
+#define __NR_fstat   80
+
 #else
 #error unknown
 #endif

src/as/arch/riscv64/asm_code.c

@@ -134,17 +134,42 @@ static unsigned char *asm_2ri(Inst *inst, Code *code) {
     }
   }
   switch (inst->op) {
-  case ADDI:   W_ADDI(rd, rs, imm); break;
-  case ADDIW:  W_ADDIW(rd, rs, imm); break;
-  case ANDI:   W_ANDI(rd, rs, imm); break;
-  case ORI:    W_ORI(rd, rs, imm); break;
-  case XORI:   W_XORI(rd, rs, imm); break;
-  case SLLI:   W_SLLI(rd, rs, imm); break;
-  case SLLIW:  W_SLLIW(rd, rs, imm); break;
-  case SRLI:   W_SRLI(rd, rs, imm); break;
-  case SRAI:   W_SRAI(rd, rs, imm); break;
-  case SLTI:   W_SLTI(rd, rs, imm); break;
-  case SLTIU:  W_SLTIU(rd, rs, imm); break;
+  case ADDI:
+  case ADDIW:
+  case ANDI:
+  case ORI:
+  case XORI:
+    if (imm >= 2048 || imm < -2048)
+      return NULL;
+    switch (inst->op) {
+    case ADDI:   W_ADDI(rd, rs, imm); break;
+    case ADDIW:  W_ADDIW(rd, rs, imm); break;
+    case ANDI:   W_ANDI(rd, rs, imm); break;
+    case ORI:    W_ORI(rd, rs, imm); break;
+    case XORI:   W_XORI(rd, rs, imm); break;
+    default: assert(false); break;
+    }
+    break;
+
+  case SLLI:
+  case SLLIW:
+  case SRLI:
+  case SRAI:
+  case SLTI:
+  case SLTIU:
+    if (imm >= 64 || (inst->op == SLLIW && imm >= 32) || imm < 0)
+      return NULL;
+    switch (inst->op) {
+    case SLLI:   W_SLLI(rd, rs, imm); break;
+    case SLLIW:  W_SLLIW(rd, rs, imm); break;
+    case SRLI:   W_SRLI(rd, rs, imm); break;
+    case SRAI:   W_SRAI(rd, rs, imm); break;
+    case SLTI:   W_SLTI(rd, rs, imm); break;
+    case SLTIU:  W_SLTIU(rd, rs, imm); break;
+    default: assert(false); break;
+    }
+    break;
+
   default: assert(false); return NULL;
   }
   return code->buf;
@@ -182,7 +207,10 @@ static unsigned char *asm_noop(Inst *inst, Code *code) {
 static unsigned char *asm_mv(Inst *inst, Code *code) {
   int rd = inst->opr1.reg.no;
   int rs = inst->opr2.reg.no;
-  C_MV(rd, rs);
+  if (rs != ZERO)
+    C_MV(rd, rs);
+  else
+    C_LI(rd, 0);
   return code->buf;
 }
 
@@ -329,7 +357,6 @@ static unsigned char *asm_sd(Inst *inst, Code *code) {
 }
 
 static unsigned char *asm_j(Inst *inst, Code *code) {
-  UNUSED(inst);
   // imm[11|4|9:8|10|6|7|3:1|5]
   C_J();
   return code->buf;
@@ -364,14 +391,14 @@ static unsigned char *asm_bxx(Inst *inst, Code *code) {
     default: break;
     }
   }
+  code->flag |= INST_LONG_OFFSET;
   static const int kFunct3Table[] = { _BEQ, _BNE, _BLT, _BGE, _BLTU, _BGEU };
   int funct3 = kFunct3Table[inst->op - BEQ];
   W_BXX(funct3, rs1, rs2, 0);
   return code->buf;
 }
 
 static unsigned char *asm_call_d(Inst *inst, Code *code) {
-  UNUSED(inst);
   W_AUIPC(RA, 0);
   W_JALR(RA, RA, 0);
   return code->buf;
@@ -382,6 +409,11 @@ static unsigned char *asm_ret(Inst *inst, Code *code) {
   return code->buf;
 }
 
+static unsigned char *asm_ecall(Inst *inst, Code *code) {
+  W_ECALL();
+  return code->buf;
+}
+
 static unsigned char *asm_3fr(Inst *inst, Code *code) {
   assert(inst->opr1.type == FREG);
   assert(inst->opr2.type == FREG);
@@ -641,6 +673,7 @@ static const AsmInstTable *table[] = {
   [BLTU] = table_bxx, [BGEU] = table_bxx,
   [CALL] = (const AsmInstTable[]){ {asm_call_d, DIRECT, NOOPERAND, NOOPERAND}, {NULL} },
   [RET] = (const AsmInstTable[]){ {asm_ret, NOOPERAND, NOOPERAND, NOOPERAND}, {NULL} },
+  [ECALL] = (const AsmInstTable[]){ {asm_ecall, NOOPERAND, NOOPERAND, NOOPERAND}, {NULL} },
 
   [FADD_D] = table_3fr, [FSUB_D] = table_3fr, [FMUL_D] = table_3fr, [FDIV_D] = table_3fr,
   [FADD_S] = table_3fr, [FSUB_S] = table_3fr, [FMUL_S] = table_3fr, [FDIV_S] = table_3fr,

src/as/arch/riscv64/inst.h

@@ -39,6 +39,7 @@ enum Opcode {
   BEQ, BNE, BLT, BGE, BLTU, BGEU,
   CALL,
   RET,
+  ECALL,
 
   FADD_D, FSUB_D, FMUL_D, FDIV_D,
   FADD_S, FSUB_S, FMUL_S, FDIV_S,