Commit f69ec6f35db93163b7f33e43129d274995c8122d
2014-12-18T16:21:07
s390: Use pc-relative insns in 31-bit mode It's silly to stick to esa/390 features when the compiler won't. Detect when brasl and larl are used by the compiler and then use them in the assembly.
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diff --git a/configure.ac b/configure.ac
index d5414f9..2941cd7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -183,6 +183,23 @@ if test x$TARGET = xX86 || test x$TARGET = xX86_WIN32 || test x$TARGET = xX86_64
fi
fi
+if test x$TARGET = xS390; then
+ AC_CACHE_CHECK([compiler uses zarch features],
+ libffi_cv_as_s390_zarch, [
+ libffi_cv_as_s390_zarch=no
+ echo 'void foo(void) { bar(); bar(); }' > conftest.c
+ if $CC $CFLAGS -S conftest.c > /dev/null 2>&1; then
+ if grep -q brasl conftest.s; then
+ libffi_cv_as_s390_zarch=yes
+ fi
+ fi
+ ])
+ if test "x$libffi_cv_as_s390_zarch" = xyes; then
+ AC_DEFINE(HAVE_AS_S390_ZARCH, 1,
+ [Define if the compiler uses zarch features.])
+ fi
+fi
+
# On PaX enable kernels that have MPROTECT enable we can't use PROT_EXEC.
AC_ARG_ENABLE(pax_emutramp,
[ --enable-pax_emutramp enable pax emulated trampolines, for we can't use PROT_EXEC],
diff --git a/src/s390/sysv.S b/src/s390/sysv.S
index df9083e..1869269 100644
--- a/src/s390/sysv.S
+++ b/src/s390/sysv.S
@@ -55,13 +55,21 @@ ffi_call_SYSV:
.cfi_rel_offset r14, 56
.cfi_def_cfa_register r13
l %r15,60(%r2) # Set up outgoing stack
+#ifdef HAVE_AS_S390_ZARCH
+ larl %r14,.Ltable
+#else
basr %r14,0 # Set up base register
.Lbase:
+#endif
sla %r3,3 # ret_type *= 8
lr %r12,%r4 # Save ret_addr
lr %r1,%r5 # Save fun
lr %r0,%r6 # Install static chain
+#ifdef HAVE_AS_S390_ZARCH
+ la %r14,0(%r14,%r3) # Set return address
+#else
la %r14,.Ltable-.Lbase(%r14,%r3) # Set return address
+#endif
lm %r2,%r6,8(%r13) # Load arguments
ld %f0,64(%r13)
ld %f2,72(%r13)
@@ -141,10 +149,12 @@ ffi_closure_SYSV:
.cfi_rel_offset r13, 52
.cfi_rel_offset r14, 56
.cfi_rel_offset r15, 60
+#ifndef HAVE_AS_S390_ZARCH
basr %r13,0 # Set up base register
.Lcbase:
- ahi %r15,-96-8 # Set up stack frame
l %r1,.Lchelper-.Lcbase(%r13) # Get helper function
+#endif
+ ahi %r15,-96-8 # Set up stack frame
st %r12,0(%r15) # Set up back chain
std %f0,64(%r12) # Save fp arguments
@@ -154,7 +164,11 @@ ffi_closure_SYSV:
st %r5,96(%r15)
la %r6,64(%r12) # FPRs
la %r5,8(%r12) # GPRs
+#ifdef HAVE_AS_S390_ZARCH
+ brasl %r14,ffi_closure_helper_SYSV
+#else
bas %r14,0(%r1,%r13) # Call helper
+#endif
lr %r15,%r12
.cfi_def_cfa_register r15
@@ -165,10 +179,11 @@ ffi_closure_SYSV:
br %r14
.cfi_endproc
+#ifndef HAVE_AS_S390_ZARCH
.align 4
.Lchelper:
.long ffi_closure_helper_SYSV-.Lcbase
-
+#endif
.size ffi_closure_SYSV,.-ffi_closure_SYSV