commit 1c04069c7a2bfa78c0d49d730bf089be7bf3b8b8
author Daniel Verkamp <dverkamp@google.com> Fri Jan 31 11:52:14 2025 -0800
committer Daniel Verkamp <dverkamp@google.com> Mon Feb 03 14:29:12 2025 -0800
tree 03a4e40b36566696a6378ac40da9b73727dd2059
parent 076a08b8ce8f154400339b9dfe6c7be6cabcb792

Provide x86_64 mem* functions in librust_baremetal.

On arm/arm64, these functions (memset, memcpy, etc.) are provided by
libarm-optimized-routines-mem, which is included in librust_baremetal.
However, that library does not provide x86_64 implementations, so we
include the same assembly versions of these functions used elsewhere in
Bionic to satisfy downstream librust_baremetal users.

The librust_baremetal library is now also explicitly disabled for 32-bit
x86 and arm; the Virtualization module where librust_baremetal is used
only works on 64-bit platforms for now.

Bug: 389669171
Test: link x86_64 pvmfw
Change-Id: I63d88b1d05f84f511ecfca4262c30858fda08eb9

libc/Android.bp

diff --git a/libc/Android.bp b/libc/Android.bp
index ee50dad..76f0dfb 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -2079,6 +2079,7 @@
 
 // This library contains the following unresolved symbols:
 //     __errno
+//     __x86_shared_cache_size_half (x86_64 only)
 //     abort
 //     async_safe_fatal_va_list
 cc_library_static {
@@ -2098,11 +2099,33 @@
         "bionic/strtol.cpp",
     ],
     arch: {
+        arm: {
+            enabled: false,
+        },
         arm64: {
             srcs: [
                 "arch-arm64/string/__memcpy_chk.S",
             ],
         },
+        x86: {
+            enabled: false,
+        },
+        x86_64: {
+            srcs: [
+                "arch-x86_64/string/sse2-memmove-slm.S",
+                "arch-x86_64/string/sse2-memset-slm.S",
+                "arch-x86_64/string/sse2-stpcpy-slm.S",
+                "arch-x86_64/string/sse2-stpncpy-slm.S",
+                "arch-x86_64/string/sse2-strcat-slm.S",
+                "arch-x86_64/string/sse2-strcpy-slm.S",
+                "arch-x86_64/string/sse2-strlen-slm.S",
+                "arch-x86_64/string/sse2-strncat-slm.S",
+                "arch-x86_64/string/sse2-strncpy-slm.S",
+                "arch-x86_64/string/sse4-memcmp-slm.S",
+                "arch-x86_64/string/ssse3-strcmp-slm.S",
+                "arch-x86_64/string/ssse3-strncmp-slm.S",
+            ],
+        },
     },
     whole_static_libs: [
         "//external/llvm-libc:llvmlibc",