Support hardware divide instruction

Bug: 11299025

Uses sdiv for division and a combo of sdiv, mul and sub for modulus.
Only does this on processors that are capable of the sdiv instruction, as determined
by the build system.

Also provides a command line arg --instruction-set-features= to allow cross compilation.
Makefile adds the --instruction-set-features= arg to build-time dex2oat runs and defaults
it to something obtained from the target architecture.

Provides a GetInstructionSetFeatures() function on CompilerDriver that can be
queried for various features.  The only feature supported right now is hasDivideInstruction().

Also adds a few more instructions to the ARM disassembler

b/11535253 is an addition to this CL to be done later.

Change-Id: Ia8aaf801fd94bc71e476902749cf20f74eba9f68

1 files changed, 29 insertions, 0 deletions

diff --git a/runtime/utils.cc b/runtime/utils.cc
index 9796b9963..e039581b0 100644
--- a/runtime/utils.cc
+++ b/runtime/utils.cc
@@ -889,6 +889,35 @@ void Split(const std::string& s, char separator, std::vector<std::string>& resul
   }
 }
 
+std::string Trim(std::string s) {
+  std::string result;
+  unsigned int start_index = 0;
+  unsigned int end_index = s.size() - 1;
+
+  // Skip initial whitespace.
+  while (start_index < s.size()) {
+    if (!isspace(s[start_index])) {
+      break;
+    }
+    start_index++;
+  }
+
+  // Skip terminating whitespace.
+  while (end_index >= start_index) {
+    if (!isspace(s[end_index])) {
+      break;
+    }
+    end_index--;
+  }
+
+  // All spaces, no beef.
+  if (end_index < start_index) {
+    return "";
+  }
+  // Start_index is the first non-space, end_index is the last one.
+  return s.substr(start_index, end_index - start_index + 1);
+}
+
 template <typename StringT>
 std::string Join(std::vector<StringT>& strings, char separator) {
   if (strings.empty()) {