Simplify

Author: rui314

src/passes.cc

@@ -2435,27 +2435,6 @@ static void set_virtual_addresses_regular(Context<E> &ctx) {
   std::vector<Chunk<E> *> &chunks = ctx.chunks;
   u64 addr = ctx.arg.image_base;
 
-  // TLS chunks alignments are special: in addition to having their virtual
-  // addresses aligned, they also have to be aligned when the region of
-  // tls_begin is copied to a new thread's storage area. In other words, their
-  // offset against tls_begin also has to be aligned.
-  //
-  // A good way to achieve this is to take the largest alignment requirement
-  // of all TLS sections and make tls_begin also aligned to that.
-  Chunk<E> *first_tls_chunk = nullptr;
-  u64 tls_alignment = 1;
-  for (Chunk<E> *chunk : chunks) {
-    if (chunk->shdr.sh_flags & SHF_TLS) {
-      if (!first_tls_chunk)
-        first_tls_chunk = chunk;
-      tls_alignment = std::max(tls_alignment, (u64)chunk->shdr.sh_addralign);
-    }
-  }
-
-  auto alignment = [&](Chunk<E> *chunk) {
-    return chunk == first_tls_chunk ? tls_alignment : (u64)chunk->shdr.sh_addralign;
-  };
-
   auto is_tbss = [](Chunk<E> *chunk) {
     return (chunk->shdr.sh_type == SHT_NOBITS) && (chunk->shdr.sh_flags & SHF_TLS);
   };
@@ -2527,7 +2506,7 @@ static void set_virtual_addresses_regular(Context<E> &ctx) {
     if (is_tbss(chunks[i])) {
       u64 addr2 = addr;
       for (;;) {
-        addr2 = align_to(addr2, alignment(chunks[i]));
+        addr2 = align_to(addr2, chunks[i]->shdr.sh_addralign);
         chunks[i]->shdr.sh_addr = addr2;
         addr2 += chunks[i]->shdr.sh_size;
         if (i + 2 == chunks.size() || !is_tbss(chunks[i + 1]))
@@ -2537,7 +2516,7 @@ static void set_virtual_addresses_regular(Context<E> &ctx) {
       continue;
     }
 
-    addr = align_to(addr, alignment(chunks[i]));
+    addr = align_to(addr, chunks[i]->shdr.sh_addralign);
     chunks[i]->shdr.sh_addr = addr;
     addr += chunks[i]->shdr.sh_size;
   }

test/tls-alignment-multi.sh

@@ -9,42 +9,39 @@
 # order to be triggered.
 
 cat <<EOF | $CC -fPIC -c -o $t/a.o -xc -
-#include <assert.h>
-#include <stdlib.h>
+#include <stdio.h>
 
 // .tdata
 _Thread_local int x = 42;
+
 // .tbss
-__attribute__ ((aligned(64)))
-_Thread_local int y = 0;
+__attribute__((aligned(64))) _Thread_local int y;
 
-void *verify(void *unused) {
-  assert((unsigned long)(&y) % 64 == 0);
+void *test(void *) {
+  printf("%p %lu", &y, (unsigned long)&y % 64);
   return NULL;
 }
 EOF
 
 cat <<EOF | $CC -fPIC -c -o $t/b.o -xc -
+#include <stdio.h>
 #include <pthread.h>
 #include <dlfcn.h>
-#include <assert.h>
-void *(*verify)(void *);
 
 int main() {
-  void *handle = dlopen("a.so", RTLD_NOW);
-  assert(handle);
-  *(void**)(&verify) = dlsym(handle, "verify");
-  assert(verify);
-
-  pthread_t thread;
+  void *handle = dlopen("c.so", RTLD_NOW);
+  void *(*test)(void *) = dlsym(handle, "test");
+  pthread_t th;
 
-  verify(NULL);
+  test(NULL);
+  printf(" ");
 
-  pthread_create(&thread, NULL, verify, NULL);
-  pthread_join(thread, NULL);
+  pthread_create(&th, NULL, test, NULL);
+  pthread_join(th, NULL);
+  printf("\n");
 }
 EOF
 
-$CC -B. -shared -o $t/a.so $t/a.o
+$CC -B. -shared -o $t/c.so $t/a.o
 $CC -B. -ldl -pthread -o $t/exe $t/b.o -Wl,-rpath,$t
-$QEMU $t/exe
+$QEMU $t/exe | grep -E '^0x[0-9a-f]+ 0 0x[0-9a-f]+ 0$'