Using libc assembler code in dhrystone stdlib.c

1 files changed, 208 insertions, 0 deletions

diff --git a/dhrystone/stdlib.c b/dhrystone/stdlib.c
index 4229aa2..2ff7ba3 100644
--- a/dhrystone/stdlib.c
+++ b/dhrystone/stdlib.c
@@ -38,12 +38,97 @@ char *malloc(int size)
 	return p;
 }
 
+#if 0
 void *memcpy(char *dest, const char *src, int n)
 {
 	while (n--)
 		*(dest++) = *(src++);
 }
+#else
+/* copy&paste from disassembled libc */
+asm (
+"               .global memcpy;      "
+"  memcpy:      xor     a5,a1,a0;    "
+"               slli    a4,a5,0x1e;  "
+"               add     a7,a0,a2;    "
+"               bnez    a4,.M1;      "
+"               li      a5,3;        "
+"               bleu    a2,a5,.M2;   "
+"               slli    a5,a0,0x1e;  "
+"               bnez    a5,.M3;      "
+"               andi    a6,a7,-4;    "
+"               addi    a5,a6,-32;   "
+"               mv      a4,a0;       "
+"               bltu    a0,a5,.M4;   "
+"  .M9:         mv      a3,a1;       "
+"               mv      a5,a4;       "
+"               bleu    a6,a4,.M5;   "
+"  .M6:         lw      a2,0(a3);    "
+"               addi    a5,a5,4;     "
+"               addi    a3,a3,4;     "
+"               sw      a2,-4(a5);   "
+"               bltu    a5,a6,.M6;   "
+"               not     a5,a4;       "
+"               add     a6,a5,a6;    "
+"               andi    a6,a6,-4;    "
+"               addi    a6,a6,4;     "
+"               add     a4,a4,a6;    "
+"               add     a1,a1,a6;    "
+"  .M5:         bltu    a4,a7,.M7;   "
+"  .M11:        ret;                 "
+"  .M3:         mv      a4,a0;       "
+"  .M8:         lbu     a5,0(a1);    "
+"               addi    a4,a4,1;     "
+"               addi    a1,a1,1;     "
+"               sb      a5,-1(a4);   "
+"               slli    a5,a4,0x1e;  "
+"               bnez    a5,.M8;      "
+"               andi    a6,a7,-4;    "
+"               addi    a5,a6,-32;   "
+"               bleu    a5,a4,.M9;   "
+"  .M4:         lw      t6,0(a1);    "
+"               lw      t5,4(a1);    "
+"               lw      t4,8(a1);    "
+"               lw      t3,12(a1);   "
+"               lw      t2,16(a1);   "
+"               lw      t1,20(a1);   "
+"               lw      t0,24(a1);   "
+"               lw      a2,28(a1);   "
+"               addi    a1,a1,36;    "
+"               addi    a4,a4,36;    "
+"               lw      a3,-4(a1);   "
+"               sw      t6,-36(a4);  "
+"               sw      t5,-32(a4);  "
+"               sw      t4,-28(a4);  "
+"               sw      t3,-24(a4);  "
+"               sw      t2,-20(a4);  "
+"               sw      t1,-16(a4);  "
+"               sw      t0,-12(a4);  "
+"               sw      a2,-8(a4);   "
+"               sw      a3,-4(a4);   "
+"               bltu    a4,a5,.M4;   "
+"               j       .M9;         "
+"  .M1:         mv      a4,a0;       "
+"               bleu    a7,a0,.M10;  "
+"  .M7:         lbu     a5,0(a1);    "
+"               addi    a4,a4,1;     "
+"               addi    a1,a1,1;     "
+"               sb      a5,-1(a4);   "
+"               bltu    a4,a7,.M7;   "
+"  .M12:        ret;                 "
+"  .M2:         mv      a4,a0;       "
+"               bleu    a7,a0,.M11;  "
+"               lbu     a5,0(a1);    "
+"               addi    a4,a4,1;     "
+"               addi    a1,a1,1;     "
+"               sb      a5,-1(a4);   "
+"               bltu    a4,a7,.M7;   "
+"               j       .M12;        "
+"  .M10:        ret;                 "
+);
+#endif
 
+#if 0
 char *strcpy(char *dest, const char *src)
 {
 	char *ret = dest;
@@ -53,7 +138,55 @@ char *strcpy(char *dest, const char *src)
 	while (*(src++));
 	return ret;
 }
+#else
+/* copy&paste from disassembled libc */
+asm (
+"               .global strcpy;      "
+"  strcpy:      or      a5,a0,a1;    "
+"               slli    a4,a5,0x1e;  "
+"               bnez    a4,.S1;      "
+"               lw      a4,0(a1);    "
+"               lui     a3,0x7f7f8;  "
+"               addi    a3,a3,-129;  "
+"               and     a5,a4,a3;    "
+"               add     a5,a5,a3;    "
+"               or      a7,a4,a3;    "
+"               or      a7,a7,a5;    "
+"               li      a5,-1;       "
+"               mv      a2,a0;       "
+"               bne     a7,a5,.S2;   "
+"  .S3:         addi    a2,a2,4;     "
+"               addi    a1,a1,4;     "
+"               sw      a4,-4(a2);   "
+"               lw      a4,0(a1);    "
+"               and     a5,a4,a3;    "
+"               or      a6,a4,a3;    "
+"               add     a5,a5,a3;    "
+"               or      a5,a6,a5;    "
+"               beq     a5,a7,.S3;   "
+"  .S2:         lbu     a5,0(a1);    "
+"               lbu     a4,1(a1);    "
+"               lbu     a3,2(a1);    "
+"               sb      a5,0(a2);    "
+"               beqz    a5,.S4;      "
+"               sb      a4,1(a2);    "
+"               beqz    a4,.S4;      "
+"               sb      a3,2(a2);    "
+"               bnez    a3,.S5;      "
+"  .S4:         ret;                 "
+"  .S5:         sb      zero,3(a2);  "
+"               ret;                 "
+"  .S1:         mv      a5,a0;       "
+"  .S6:         lbu     a4,0(a1);    "
+"               addi    a5,a5,1;     "
+"               addi    a1,a1,1;     "
+"               sb      a4,-1(a5);   "
+"               bnez    a4,.S6;      "
+"               ret;                 "
+);
+#endif
 
+#if 0
 int strcmp(const char *s1, const char *s2)
 {
 	// printf("[strcmp()]");
@@ -67,6 +200,81 @@ int strcmp(const char *s1, const char *s2)
 		s1++, s2++;
 	}
 }
+#else
+/* copy&paste from disassembled libc */
+asm (
+"               .global strcmp;      "
+"  strcmp:      or      a4,a0,a1;    "
+"               li      t2,-1;       "
+"               andi    a4,a4,3;     "
+"               bnez    a4,.K1;      "
+"               lui     t3,0x7f7f8;  "
+"               addi    t3,t3,-129;  "
+"  .K6:         lw      a2,0(a0);    "
+"               lw      a3,0(a1);    "
+"               and     t0,a2,t3;    "
+"               or      t1,a2,t3;    "
+"               add     t0,t0,t3;    "
+"               or      t0,t0,t1;    "
+"               bne     t0,t2,.K2;   "
+"               bne     a2,a3,.K3;   "
+"               lw      a2,4(a0);    "
+"               lw      a3,4(a1);    "
+"               and     t0,a2,t3;    "
+"               or      t1,a2,t3;    "
+"               add     t0,t0,t3;    "
+"               or      t0,t0,t1;    "
+"               bne     t0,t2,.K4;   "
+"               bne     a2,a3,.K3;   "
+"               lw      a2,8(a0);    "
+"               lw      a3,8(a1);    "
+"               and     t0,a2,t3;    "
+"               or      t1,a2,t3;    "
+"               add     t0,t0,t3;    "
+"               or      t0,t0,t1;    "
+"               bne     t0,t2,.K5;   "
+"               addi    a0,a0,12;    "
+"               addi    a1,a1,12;    "
+"               beq     a2,a3,.K6;   "
+"  .K3:         slli    a4,a2,0x10;  "
+"               slli    a5,a3,0x10;  "
+"               bne     a4,a5,.K7;   "
+"               srli    a4,a2,0x10;  "
+"               srli    a5,a3,0x10;  "
+"               sub     a0,a4,a5;    "
+"               andi    a1,a0,255;   "
+"               bnez    a1,.K8;      "
+"               ret;                 "
+"  .K7:         srli    a4,a4,0x10;  "
+"               srli    a5,a5,0x10;  "
+"               sub     a0,a4,a5;    "
+"               andi    a1,a0,255;   "
+"               bnez    a1,.K8;      "
+"               ret;                 "
+"  .K8:         andi    a4,a4,255;   "
+"               andi    a5,a5,255;   "
+"               sub     a0,a4,a5;    "
+"               ret;                 "
+"  .K1:         lbu     a2,0(a0);    "
+"               lbu     a3,0(a1);    "
+"               addi    a0,a0,1;     "
+"               addi    a1,a1,1;     "
+"               bne     a2,a3,.K9;   "
+"               bnez    a2,.K1;      "
+"  .K9:         sub     a0,a2,a3;    "
+"               ret;                 "
+"  .K4:         addi    a0,a0,4;     "
+"               addi    a1,a1,4;     "
+"  .K2:         bne     a2,a3,.K1;   "
+"               li      a0,0;        "
+"               ret;                 "
+"  .K5:         addi    a0,a0,8;     "
+"               addi    a1,a1,8;     "
+"               bne     a2,a3,.K1;   "
+"               li      a0,0;        "
+"               ret;                 "
+);
+#endif
 
 static void printf_c(int c)
 {