feat(arm): add TLS Local Exec code generation and linker relocations

arm-gen.c

@@ -572,7 +572,7 @@ static void load_value(SValue *sv, int r)
 void load(int r, SValue *sv)
 {
   int v, ft, fc, fr, sign;
-  uint32_t op;
+  uint32_t op, base;
   SValue v1;
 
   fr = sv->r;
@@ -588,7 +588,15 @@ void load(int r, SValue *sv)
 
   v = fr & VT_VALMASK;
   if (fr & VT_LVAL) {
-    uint32_t base = 0xB; // fp
+    if ((fr & VT_SYM) && sv->sym->type.t & VT_TLS) {
+        uint32_t op;
+        o(0xee1d0fe0); /* mrc p15, 0, lr, c13, c0, 3 */
+        op = 0xe510e000; /* ldr r, [lr, #0] */
+        greloca(cur_text_section, sv->sym, ind, R_ARM_TLS_LE32, 0);
+        o(op | (intr(r) << 12));
+        return;
+    }
+    base = 0xB; // fp
     if(v == VT_LLOCAL) {
       v1.type.t = VT_PTR;
       v1.r = VT_LOCAL | VT_LVAL;
@@ -703,7 +711,7 @@ void store(int r, SValue *sv)
 {
   SValue v1;
   int v, ft, fc, fr, sign;
-  uint32_t op;
+  uint32_t op, base;
 
   fr = sv->r;
   ft = sv->type.t;
@@ -718,7 +726,15 @@ void store(int r, SValue *sv)
 
   v = fr & VT_VALMASK;
   if (fr & VT_LVAL || fr == VT_LOCAL) {
-    uint32_t base = 0xb; /* fp */
+    if ((fr & VT_SYM) && sv->sym->type.t & VT_TLS) {
+        uint32_t op;
+        o(0xee1d0fe0); /* mrc p15, 0, lr, c13, c0, 3 */
+        op = 0xe500e000; /* str r, [lr, #0] */
+        greloca(cur_text_section, sv->sym, ind, R_ARM_TLS_LE32, 0);
+        o(op | (intr(r) << 12));
+        return;
+    }
+    base = 0xb; /* fp */
     if(v < VT_CONST) {
       base=intr(v);
       v=VT_LOCAL;

arm-link.c

@@ -44,6 +44,7 @@ ST_FUNC int code_reloc (int reloc_type)
 	case R_ARM_TARGET1:
 	case R_ARM_MOVT_PREL:
 	case R_ARM_MOVW_PREL_NC:
+	case R_ARM_TLS_LE32:
             return 0;
 
         case R_ARM_PC24:
@@ -70,6 +71,7 @@ ST_FUNC int gotplt_entry_type (int reloc_type)
 	case R_ARM_COPY:
 	case R_ARM_GLOB_DAT:
 	case R_ARM_JUMP_SLOT:
+	case R_ARM_TLS_LE32:
             return NO_GOTPLT_ENTRY;
 
         case R_ARM_PC24:
@@ -430,6 +432,36 @@ ST_FUNC void relocate(TCCState *s1, ElfW_Rel *rel, int type, unsigned char *ptr,
 #endif
             /* do nothing */
             return;
+        case R_ARM_TLS_LE32:
+            {
+                ElfW(Sym) *sym;
+                Section *sec;
+                int32_t x;
+                addr_t tls_start = 0, tls_end = 0, tls_align = 1;
+                int i;
+
+                sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+                sec = s1->sections[sym->st_shndx];
+
+                for (i = 1; i < s1->nb_sections; i++) {
+                    Section *s = s1->sections[i];
+                    if (s->sh_flags & SHF_TLS && s->sh_size) {
+                        if (!tls_start || s->sh_addr < tls_start)
+                            tls_start = s->sh_addr;
+                        if (s->sh_addr + s->sh_size > tls_end)
+                            tls_end = s->sh_addr + s->sh_size;
+                        if (s->sh_addralign > tls_align)
+                            tls_align = s->sh_addralign;
+                    }
+                }
+                if (tls_end > tls_start) {
+                    x = val - tls_start + 8;
+                } else {
+                    x = val - sec->sh_addr - sec->data_offset + 8;
+                }
+                add32le(ptr, x);
+            }
+            return;
         default:
             fprintf(stderr,"FIXME: handle reloc type %d at %x [%p] to %x\n",
                 type, (unsigned)addr, ptr, (unsigned)val);

tests/tests2/Makefile

@@ -19,8 +19,8 @@ ifeq (,$(filter i386 x86_64,$(ARCH)))
  SKIP += 85_asm-outside-function.test # x86 asm
  SKIP += 127_asm_goto.test    # hardcodes x86 asm
 endif
-ifeq (,$(filter x86_64 riscv64 arm64,$(ARCH)))
+ifeq (,$(filter x86_64 riscv64 arm64 arm,$(ARCH)))
- SKIP += 144_tls.test # TLS only implemented on x86_64 so far
+ SKIP += 144_tls.test # TLS only implemented on these architectures so far
 endif
 ifeq ($(CONFIG_backtrace),no)
  SKIP += 113_btdll.test