Add LoongArch detection

- detect the LoongArch architecture, define Q_PROCESSOR_LOONGARCH and
  Q_PROCESSOR_LOONGARCH_{32,64} appropriately
- document the macros as being available starting from 6.5
- add LoongArch ELF support in QElfParser

Change-Id: I438146af49ec3adacacec84c27c9f4abaa542830
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/global/archdetect.cpp

@@ -25,6 +25,10 @@
 #  define ARCH_PROCESSOR "x86_64"
 #elif defined(Q_PROCESSOR_IA64)
 #  define ARCH_PROCESSOR "ia64"
+#elif defined(Q_PROCESSOR_LOONGARCH_32)
+#  define ARCH_PROCESSOR "loongarch32"
+#elif defined(Q_PROCESSOR_LOONGARCH_64)
+#  define ARCH_PROCESSOR "loongarch64"
 #elif defined(Q_PROCESSOR_M68K)
 #  define ARCH_PROCESSOR "m68k"
 #elif defined(Q_PROCESSOR_MIPS_64)

src/corelib/global/qprocessordetection.h

@@ -199,6 +199,20 @@
 #  define Q_PROCESSOR_WORDSIZE   8
 // Q_BYTE_ORDER not defined, use endianness auto-detection
 
+/*
+    LoongArch family, known variants: 32- and 64-bit
+
+    LoongArch is little-endian.
+*/
+#elif defined(__loongarch__)
+#  define Q_PROCESSOR_LOONGARCH
+#  if __loongarch_grlen == 64
+#    define Q_PROCESSOR_LOONGARCH_64
+#  else
+#    define Q_PROCESSOR_LOONGARCH_32
+#  endif
+#  define Q_BYTE_ORDER Q_LITTLE_ENDIAN
+
 /*
     Motorola 68000 family, no revisions or variants
 

src/corelib/global/qprocessordetection.qdoc

@@ -105,6 +105,40 @@
     \sa QSysInfo::buildCpuArchitecture()
 */
 
+/*!
+    \macro Q_PROCESSOR_LOONGARCH
+    \relates <QtProcessorDetection>
+    \since 6.5
+
+    Defined if the application is compiled for LoongArch processors.
+
+    \sa QSysInfo::buildCpuArchitecture()
+*/
+
+/*!
+    \macro Q_PROCESSOR_LOONGARCH_32
+    \relates <QtProcessorDetection>
+    \since 6.5
+
+    Defined if the application is compiled for 32-bit LoongArch processors.
+    The \l Q_PROCESSOR_LOONGARCH macro is also defined when
+    Q_PROCESSOR_LOONGARCH_32 is defined.
+
+    \sa QSysInfo::buildCpuArchitecture()
+*/
+
+/*!
+    \macro Q_PROCESSOR_LOONGARCH_64
+    \relates <QtProcessorDetection>
+    \since 6.5
+
+    Defined if the application is compiled for 64-bit LoongArch processors.
+    The \l Q_PROCESSOR_LOONGARCH macro is also defined when
+    Q_PROCESSOR_LOONGARCH_64 is defined.
+
+    \sa QSysInfo::buildCpuArchitecture()
+*/
+
 /*!
     \macro Q_PROCESSOR_M68K
     \relates <QtProcessorDetection>

src/corelib/plugin/qelfparser_p.cpp

@@ -122,6 +122,8 @@ struct ElfMachineCheck
             EM_PARISC
 #elif defined(Q_PROCESSOR_IA64)
             EM_IA_64
+#elif defined(Q_PROCESSOR_LOONGARCH)
+            EM_LOONGARCH
 #elif defined(Q_PROCESSOR_M68K)
             EM_68K
 #elif defined(Q_PROCESSOR_MIPS)
@@ -387,6 +389,9 @@ Q_DECL_UNUSED Q_DECL_COLD_FUNCTION static QDebug &operator<<(QDebug &d, ElfHeade
     case EM_BLACKFIN:   d << ", Blackfin"; break;
 #endif
     case EM_IA_64:      d << ", IA-64"; break;
+#ifdef EM_LOONGARCH
+    case EM_LOONGARCH:  d << ", LoongArch"; break;
+#endif
     case EM_MIPS:       d << ", MIPS"; break;
     case EM_PARISC:     d << ", HPPA"; break;
     case EM_PPC:        d << ", PowerPC"; break;