Implement support functions ourselves instead of relying on libgcc

src/Makefile

@@ -32,16 +32,12 @@ limine.bin: libgcc.a $(BC) $(ASM_OBJ)
 	llvm-link $(BC) -o bundle.bc
 	opt --O$(OPT_LEVEL) bundle.bc -o optimised_bundle.bc
 	clang --target=i386-elf -O$(OPT_LEVEL) -c optimised_bundle.bc -o optimised_bundle.o
-	ld.lld optimised_bundle.o $(ASM_OBJ) libgcc.a $(INTERNAL_LDFLAGS) -o stage2.elf
+	ld.lld optimised_bundle.o $(ASM_OBJ) $(INTERNAL_LDFLAGS) -o stage2.elf
 	llvm-objcopy -O binary stage2.elf stage2.bin
 	gzip -9 stage2.bin
 	$(MAKE) -C decompressor
 	cd bootsect && nasm bootsect.asm -fbin -o ../limine.bin
 
-libgcc.a:
-	curl https://mirror.netcologne.de/archlinux/core/os/x86_64/gcc-10.2.0-2-x86_64.pkg.tar.zst | \
-		tar -I zstd -xv --strip-components=6 --occurrence=1 usr/lib/gcc/x86_64-pc-linux-gnu/10.2.0/32/libgcc.a
-
 %.bc: %.c
 	clang --target=i386-elf $(CFLAGS) $(INTERNAL_CFLAGS) -c $< -o $@
 

src/decompressor/Makefile

@@ -30,7 +30,7 @@ decompressor.bin: $(BC)
 	llvm-link $(BC) -o bundle.bc
 	opt --O$(OPT_LEVEL) bundle.bc -o optimised_bundle.bc
 	clang --target=i386-elf -O$(OPT_LEVEL) -c optimised_bundle.bc -o optimised_bundle.o
-	ld.lld optimised_bundle.o ../libgcc.a $(INTERNAL_LDFLAGS) -o decompressor.elf
+	ld.lld optimised_bundle.o $(INTERNAL_LDFLAGS) -o decompressor.elf
 	llvm-objcopy -O binary decompressor.elf decompressor.bin
 
 %.bc: %.c

src/lib/builtins.asm

@@ -1,5 +1,50 @@
 section .text
 
+global __ashldi3
+__ashldi3:
+    push ebx
+    mov eax, dword [esp+8]
+    mov edx, dword [esp+12]
+    mov ecx, dword [esp+16]
+
+    test ecx, ecx
+    jz .done
+  .next:
+    shl edx, 1
+    shl eax, 1
+    setc bl
+    or dl, bl
+    loop .next
+
+  .done:
+    pop ebx
+    ret
+
+global __udivdi3
+__udivdi3:
+    mov eax, dword [esp+4]
+    mov edx, dword [esp+8]
+    div dword [esp+12]
+    xor edx, edx
+    ret
+
+global __divdi3
+__divdi3:
+    mov eax, dword [esp+4]
+    mov edx, dword [esp+8]
+    idiv dword [esp+12]
+    xor edx, edx
+    ret
+
+global __umoddi3
+__umoddi3:
+    mov eax, dword [esp+4]
+    mov edx, dword [esp+8]
+    div dword [esp+12]
+    mov eax, edx
+    xor edx, edx
+    ret
+
 global memcpy
 memcpy:
     push esi