1 files changed, 118 insertions, 0 deletions
diff --git a/libffi/src/arm/gentramp.sh b/libffi/src/arm/gentramp.sh
new file mode 100755
index 00000000000..74f0b867dae
--- /dev/null
+++ b/libffi/src/arm/gentramp.sh
@@ -0,0 +1,118 @@
+#!/bin/sh
+
+# -----------------------------------------------------------------------
+#  gentramp.sh - Copyright (c) 2010, Plausible Labs Cooperative, Inc.
+#  
+#  ARM Trampoline Page Generator
+#
+#  Permission is hereby granted, free of charge, to any person obtaining
+#  a copy of this software and associated documentation files (the
+#  ``Software''), to deal in the Software without restriction, including
+#  without limitation the rights to use, copy, modify, merge, publish,
+#  distribute, sublicense, and/or sell copies of the Software, and to
+#  permit persons to whom the Software is furnished to do so, subject to
+#  the following conditions:
+#
+#  The above copyright notice and this permission notice shall be included
+#  in all copies or substantial portions of the Software.
+#
+#  THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
+#  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+#  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+#  NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+#  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+#  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+#  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+#  DEALINGS IN THE SOFTWARE.
+#  -----------------------------------------------------------------------
+
+PROGNAME=$0
+
+# Each trampoline is exactly 3 instructions, or 12 bytes. If any of these values change,
+# the entire arm trampoline implementation must be updated to match, too.
+
+# Size of an individual trampoline, in bytes
+TRAMPOLINE_SIZE=12
+
+# Page size, in bytes
+PAGE_SIZE=4096
+
+# Compute the size of the reachable config page; The first 16 bytes of the config page
+# are unreachable due to our maximum pc-relative ldr offset.
+PAGE_AVAIL=`expr $PAGE_SIZE - 16`
+
+# Compute the number of of available trampolines. 
+TRAMPOLINE_COUNT=`expr $PAGE_AVAIL / $TRAMPOLINE_SIZE`
+
+header () {
+    echo "# GENERATED CODE - DO NOT EDIT"
+    echo "# This file was generated by $PROGNAME"
+    echo ""
+
+    # Write out the license header
+cat << EOF
+#  Copyright (c) 2010, Plausible Labs Cooperative, Inc.
+#  
+#  Permission is hereby granted, free of charge, to any person obtaining
+#  a copy of this software and associated documentation files (the
+#  ``Software''), to deal in the Software without restriction, including
+#  without limitation the rights to use, copy, modify, merge, publish,
+#  distribute, sublicense, and/or sell copies of the Software, and to
+#  permit persons to whom the Software is furnished to do so, subject to
+#  the following conditions:
+#
+#  The above copyright notice and this permission notice shall be included
+#  in all copies or substantial portions of the Software.
+#
+#  THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
+#  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+#  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+#  NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+#  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+#  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+#  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+#  DEALINGS IN THE SOFTWARE.
+#  -----------------------------------------------------------------------
+
+EOF
+
+    # Write out the trampoline table, aligned to the page boundary
+    echo ".text"
+    echo ".align 12"
+    echo ".globl _ffi_closure_trampoline_table_page"
+    echo "_ffi_closure_trampoline_table_page:"
+}
+
+
+# WARNING - Don't modify the trampoline code size without also updating the relevent libffi code
+trampoline () {
+    cat << END
+
+    // trampoline
+    // Save to stack
+    stmfd sp!, {r0-r3}
+
+    // Load the context argument from the config page.
+    // This places the first usable config value at _ffi_closure_trampoline_table-4080
+    // This accounts for the above 4-byte stmfd instruction, plus 8 bytes constant when loading from pc.
+    ldr r0, [pc, #-4092]
+
+    // Load the jump address from the config page.
+    ldr pc, [pc, #-4092]
+
+END
+}
+
+main () {
+    # Write out the header
+    header
+
+    # Write out the trampolines
+    local i=0
+    while [ $i -lt ${TRAMPOLINE_COUNT} ]; do
+        trampoline
+        local i=`expr $i + 1`
+    done
+}
+
+main