PPC: Support ELF v2 on powerpc64 big-endian

Detect ELF v2 on PowerPC 64-bit systems. Check for `_CALL_ELF`
preprocessor macro.

Fixes #21191

compiler/GHC/CmmToAsm/PPC/CodeGen.hs

@@ -1912,8 +1912,15 @@ genCCall' config gcp target dest_regs args
                          -- "Single precision floating point values
                          -- are mapped to the second word in a single
                          -- doubleword"
-                         GCP64ELF 1      -> stackOffset' + 4
-                         _               -> stackOffset'
+                         GCP64ELF 1 -> stackOffset' + 4
+                         -- ELF v2 ABI Revision 1.5 Section 2.2.3.3. requires
+                         -- a single-precision floating-point value
+                         -- to be mapped to the least-significant
+                         -- word in a single doubleword.
+                         GCP64ELF 2 -> case platformByteOrder platform of
+                                       BigEndian    -> stackOffset' + 4
+                                       LittleEndian -> stackOffset'
+                         _          -> stackOffset'
                      | otherwise = stackOffset'
 
                 stackSlot = AddrRegImm sp (ImmInt stackOffset'')

libraries/ghc-platform/src/GHC/Platform/ArchOS.hs

@@ -126,8 +126,7 @@ stringEncodeArch = \case
   ArchX86           -> "i386"
   ArchX86_64        -> "x86_64"
   ArchPPC           -> "powerpc"
-  ArchPPC_64 ELF_V1 -> "powerpc64"
-  ArchPPC_64 ELF_V2 -> "powerpc64le"
+  ArchPPC_64 _      -> "powerpc64"
   ArchS390X         -> "s390x"
   ArchARM ARMv5 _ _ -> "armv5"
   ArchARM ARMv6 _ _ -> "armv6"

m4/fptools_set_haskell_platform_vars.m4

@@ -14,11 +14,9 @@ AC_DEFUN([FPTOOLS_SET_HASKELL_PLATFORM_VARS_SHELL_FUNCTIONS],
         powerpc)
             test -z "[$]2" || eval "[$]2=ArchPPC"
             ;;
-        powerpc64)
-            test -z "[$]2" || eval "[$]2=\"ArchPPC_64 ELF_V1\""
-            ;;
-        powerpc64le)
-            test -z "[$]2" || eval "[$]2=\"ArchPPC_64 ELF_V2\""
+        powerpc64*)
+            GHC_GET_POWER_ABI()
+            test -z "[$]2" || eval "[$]2=\"ArchPPC_64 $POWER_ABI\""
             ;;
         s390x)
             test -z "[$]2" || eval "[$]2=ArchS390X"

m4/ghc_get_power_abi.m4

+# GHC_GET_POWER_ABI
+# ----------------------------------
+# Get version of the PowerPC ABI
+AC_DEFUN([GHC_GET_POWER_ABI],
+[
+    AC_COMPILE_IFELSE([
+        AC_LANG_PROGRAM(
+            [],
+            [#if defined(_CALL_ELF) && _CALL_ELF == 2
+                 return 0;
+             #else
+                 not ELF v2
+             #endif]
+        )],
+        [POWER_ABI=ELF_V2],
+        [POWER_ABI=ELF_V1])
+
+        AC_SUBST(POWER_ABI)
+])

rts/AdjustorAsm.S

@@ -2,8 +2,7 @@
 
 /* ******************************** PowerPC ******************************** */
 
-#if defined(powerpc_HOST_ARCH) || defined(powerpc64_HOST_ARCH)
-#if !(defined(powerpc_HOST_ARCH) && defined(linux_HOST_OS))
+#if defined(powerpc_HOST_ARCH) && defined(aix_HOST_OS) || defined(powerpc64_HOST_ARCH) && defined(__ELF__) && (!defined(_CALL_ELF) || _CALL_ELF == 1)
     /* The following code applies, with some differences,
        to all powerpc platforms except for powerpc32-linux,
        whose calling convention is annoyingly complex.
@@ -60,12 +59,12 @@ adjustorCode:
         /* save the link */
     mflr    0
     STORE   0, LINK_SLOT(1)
-    
+
         /* set up stack frame */
     LOAD    12, FRAMESIZE_OFF(2)
 #if defined(powerpc64_HOST_ARCH)
     stdux   1, 1, 12
-#else   
+#else
     stwux   1, 1, 12
 #endif /* defined(powerpc64_HOST_ARCH) */
 
@@ -108,7 +107,7 @@ L2:
     LOAD    12, WPTR_OFF(2)
     LOAD    0, 0(12)
         /* The function we're calling will never be a nested function,
-           so we don't load r11. 
+           so we don't load r11.
         */
     mtctr   0
     LOAD    2, WS(12)
@@ -118,8 +117,7 @@ L2:
     LOAD    0, LINK_SLOT(1)
     mtlr    0
     blr
-#endif /* !(defined(powerpc_HOST_ARCH) && defined(linux_HOST_OS)) */
-#endif /* defined(powerpc_HOST_ARCH) || defined(powerpc64_HOST_ARCH) */
+#endif
 
 /* mark stack as nonexecutable */
 #if defined(__linux__) && defined(__ELF__)

rts/StgCRun.c

@@ -670,7 +670,7 @@ StgRunIsImplementedInAssembler(void)
    Everything is in assembler, so we don't have to deal with GCC...
    -------------------------------------------------------------------------- */
 
-#if defined(powerpc64_HOST_ARCH)
+#if defined(powerpc64_HOST_ARCH) && (!defined _CALL_ELF || _CALL_ELF == 1)
 /* 64-bit PowerPC ELF ABI 1.9
  *
  * Stack frame organization (see Figure 3-17, ELF ABI 1.9, p 14)

rts/StgCRunAsm.S

@@ -5,11 +5,11 @@
  * then functions StgRun/StgReturn are implemented in file StgCRun.c */
 #if !defined(USE_MINIINTERPRETER)
 
-#if defined(powerpc64le_HOST_ARCH)
-# if defined(linux_HOST_OS)
-/* 64-bit PowerPC ELF V2 ABI Revision 1.4
+#if defined(powerpc64le_HOST_ARCH) || defined(powerpc64_HOST_ARCH)
+# if defined(_CALL_ELF) && _CALL_ELF == 2
+/* 64-bit PowerPC ELF V2 ABI Revision 1.5
  *
- * Stack frame organization (see Figure 2.18, ELF V2 ABI Revision 1.4, p 31)
+ * Stack frame organization (see Figure 2.18, ELF V2 ABI Revision 1.5, p 34)
  *
  * +-> Back Chain (points to the prevoius stack frame)
  * |   Floating point register save area (f14-f31)
@@ -66,8 +66,10 @@ StgReturn:
         addi 12,1,-(8*18)
         bl _restgpr1_14
         b _restfpr_14
-# else // linux_HOST_OS
-# error Only Linux support for power64 little endian right now.
+
+	.section	.note.GNU-stack,"",@progbits
+# else // Not ELF v2
+# error Only ELF v2 supported.
 # endif
 
 #elif defined(powerpc_HOST_ARCH)
@@ -449,7 +451,7 @@ StgReturn:
 	ld.d	$fp,$sp,144
 	.cfi_restore 22
 	ld.d	$s0,$sp,136
-	.cfi_restore 23 
+	.cfi_restore 23
 	ld.d	$s1,$sp,128
 	.cfi_restore 24
 	ld.d	$s2,$sp,120

rts/adjustor/NativePowerPC.c

@@ -29,8 +29,7 @@ __asm__("obscure_ccall_ret_code:\n\t"
 extern void obscure_ccall_ret_code(void);
 #endif /* defined(linux_HOST_OS) */
 
-#if defined(powerpc_HOST_ARCH) || defined(powerpc64_HOST_ARCH)
-#if !(defined(powerpc_HOST_ARCH) && defined(linux_HOST_OS))
+#if defined(powerpc_HOST_ARCH) && defined(aix_HOST_OS) || defined(powerpc64_HOST_ARCH) && defined(__ELF__) && (!defined(_CALL_ELF) || _CALL_ELF == 1)
 
 /* !!! !!! WARNING: !!! !!!
  * This structure is accessed from AdjustorAsm.s
@@ -50,8 +49,7 @@ typedef struct AdjustorStub {
     StgInt          extrawords_plus_one;
 } AdjustorStub;
 
-#endif /* !(defined(powerpc_HOST_ARCH) && defined(linux_HOST_OS)) */
-#endif /* defined(powerpc_HOST_ARCH) || defined(powerpc64_HOST_ARCH) */
+#endif
 
 void initAdjustors(void) { }