[libunwind] b559777 - [libunwind] Remove __ANDROID_API__ < 18 workaround

[Fangrui Song via cfe-commits]

Author: Fangrui Song
Date: 2022-08-12T10:46:46-07:00
New Revision: b559777c308dcdf40a5dc8dffd35867083a46c3c

URL: https://github.com/llvm/llvm-project/commit/b559777c308dcdf40a5dc8dffd35867083a46c3c
DIFF: https://github.com/llvm/llvm-project/commit/b559777c308dcdf40a5dc8dffd35867083a46c3c.diff

LOG: [libunwind] Remove __ANDROID_API__ < 18 workaround

https://github.com/android/ndk/wiki/Changelog-r24 shows that the NDK has
moved forward to at least a minimum target API of 19. Remove old workaround.

Reviewed By: #libunwind, danalbert

Differential Revision: https://reviews.llvm.org/D131792

Added: 
    

Modified: 
    libunwind/src/AddressSpace.hpp

Removed: 
    


################################################################################
diff  --git a/libunwind/src/AddressSpace.hpp b/libunwind/src/AddressSpace.hpp
index f1ba94ed732e3..315289cd4211b 100644
--- a/libunwind/src/AddressSpace.hpp
+++ b/libunwind/src/AddressSpace.hpp
@@ -373,28 +373,6 @@ LocalAddressSpace::getEncodedP(pint_t &addr, pint_t end, uint8_t encoding,
   typedef ElfW(Addr) Elf_Addr;
 #endif
 
-static Elf_Addr calculateImageBase(struct dl_phdr_info *pinfo) {
-  Elf_Addr image_base = pinfo->dlpi_addr;
-#if defined(__ANDROID__) && __ANDROID_API__ < 18
-  if (image_base == 0) {
-    // Normally, an image base of 0 indicates a non-PIE executable. On
-    // versions of Android prior to API 18, the dynamic linker reported a
-    // dlpi_addr of 0 for PIE executables. Compute the true image base
-    // using the PT_PHDR segment.
-    // See https://github.com/android/ndk/issues/505.
-    for (Elf_Half i = 0; i < pinfo->dlpi_phnum; i++) {
-      const Elf_Phdr *phdr = &pinfo->dlpi_phdr[i];
-      if (phdr->p_type == PT_PHDR) {
-        image_base = reinterpret_cast<Elf_Addr>(pinfo->dlpi_phdr) -
-          phdr->p_vaddr;
-        break;
-      }
-    }
-  }
-#endif
-  return image_base;
-}
-
 struct _LIBUNWIND_HIDDEN dl_iterate_cb_data {
   LocalAddressSpace *addressSpace;
   UnwindInfoSections *sects;
@@ -468,7 +446,7 @@ static int findUnwindSectionsByPhdr(struct dl_phdr_info *pinfo,
   (void)pinfo_size;
 #endif
 
-  Elf_Addr image_base = calculateImageBase(pinfo);
+  Elf_Addr image_base = pinfo->dlpi_addr;
 
   // Most shared objects seen in this callback function likely don't contain the
   // target address, so optimize for that. Scan for a matching PT_LOAD segment