S390: Platform specific includes in common files

src/base/platform/platform-posix.cc

Index: src/base/platform/platform-posix.cc
diff --git a/src/base/platform/platform-posix.cc b/src/base/platform/platform-posix.cc
index 046dbb69c30f03f50a70d81114f60fd58173bb80..7e985e3fb70bc68bcc3c16789db9179dac7d298c 100644
--- a/src/base/platform/platform-posix.cc
+++ b/src/base/platform/platform-posix.cc
@@ -81,6 +81,8 @@ int OS::ActivationFrameAlignment() {
   return 8;
 #elif V8_TARGET_ARCH_MIPS
   return 8;
+#elif V8_TARGET_ARCH_S390
+  return 8;
 #else
   // Otherwise we just assume 16 byte alignment, i.e.:
   // - With gcc 4.4 the tree vectorization optimizer can generate code
@@ -185,6 +187,15 @@ void* OS::GetRandomMmapAddr() {
   // Little-endian Linux: 48 bits of virtual addressing.
   raw_addr &= V8_UINT64_C(0x3ffffffff000);
 #endif
+#elif V8_TARGET_ARCH_S390X
+  // Linux on Z uses bits 22-32 for Region Indexing, which translates to 42 bits
+  // of virtual addressing.  Truncate to 40 bits to allow kernel chance to
+  // fulfill request.
+  raw_addr &= V8_UINT64_C(0xfffffff000);
+#elif V8_TARGET_ARCH_S390
+  // 31 bits of virtual addressing.  Truncate to 29 bits to allow kernel chance
+  // to fulfill request.
+  raw_addr &= 0x1ffff000;
 #else
   raw_addr &= 0x3ffff000;
 
@@ -252,6 +263,9 @@ void OS::DebugBreak() {
 #endif  // V8_OS_NACL
 #elif V8_HOST_ARCH_X64
   asm("int $3");
+#elif V8_HOST_ARCH_S390
+  // Software breakpoint instruction is 0x0001
+  asm volatile(".word 0x0001");
 #else
 #error Unsupported host architecture.
 #endif