[commit: ghc] ghc-7.10: RTS : Fix StgRun for aarch64-linux (#9935). (5f2af66)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : ghc-7.10
Link       : http://ghc.haskell.org/trac/ghc/changeset/5f2af6646067a6a66afa450c42482b5723172593/ghc

>---------------------------------------------------------------

commit 5f2af6646067a6a66afa450c42482b5723172593
Author: Erik de Castro Lopo <erikd at mega-nerd.com>
Date:   Tue Jan 27 10:12:49 2015 +1100

    RTS : Fix StgRun for aarch64-linux (#9935).
    
    Summary:
    The GCC assembler doesn't seem to recognise the 'fp' and 'lr' register
    names which are aliases for 'x29' and 'x30' respectively.
    
    Depends on D598.
    
    Test Plan: validate
    
    Reviewers: lukexi, bgamari, austin
    
    Reviewed By: austin
    
    Subscribers: carter, thomie
    
    Differential Revision: https://phabricator.haskell.org/D599
    
    GHC Trac Issues: #9935
    
    (cherry picked from commit b9063703301f0d902b4bb2eb28ac27e9bc050ea0)


>---------------------------------------------------------------

5f2af6646067a6a66afa450c42482b5723172593
 rts/StgCRun.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/rts/StgCRun.c b/rts/StgCRun.c
index 55e0a48..f8a3f0f 100644
--- a/rts/StgCRun.c
+++ b/rts/StgCRun.c
@@ -755,12 +755,14 @@ StgRun(StgFunPtr f, StgRegTable *basereg) {
     StgRegTable * r;
     __asm__ volatile (
         /*
-         * save callee-saves registers on behalf of the STG code.
-         * floating point registers only need the bottom 64 bits preserved.
-         * x16 and x17 are ip0 and ip1, but we can't refer to them by that name with clang.
+         * Save callee-saves registers on behalf of the STG code.
+         * Floating point registers only need the bottom 64 bits preserved.
+         * We need to use the the names x16, x17, x29 and x30 instead of ip0
+         * ip1, fp and lp because one of either clang or gcc doesn't understand
+         * the later names.
          */
-        "stp fp,  lr,  [sp, #-16]!\n\t"
-        "mov fp, sp\n\t"
+        "stp x29,  x30,  [sp, #-16]!\n\t"
+        "mov x29, sp\n\t"
         "stp x16, x17, [sp, #-16]!\n\t"
         "stp x19, x20, [sp, #-16]!\n\t"
         "stp x21, x22, [sp, #-16]!\n\t"
@@ -814,12 +816,12 @@ StgRun(StgFunPtr f, StgRegTable *basereg) {
         "ldp x21, x22, [sp], #16\n\t"
         "ldp x19, x20, [sp], #16\n\t"
         "ldp x16, x17, [sp], #16\n\t"
-        "ldp fp,  lr,  [sp], #16\n\t"
+        "ldp x29,  x30,  [sp], #16\n\t"
 
       : "=r" (r)
       : "r" (f), "r" (basereg), "i" (RESERVED_C_STACK_BYTES)
         : "%x19", "%x20", "%x21", "%x22", "%x23", "%x24", "%x25", "%x26", "%x27", "%x28",
-          "%x16", "%x17", "%lr"
+          "%x16", "%x17", "%x30"
     );
     return r;
 }