runtime: do not use buggy llvm.eh.sjlj.* intrinsics

artiq/devices/runtime.py

@@ -62,6 +62,10 @@ class LinkInterface:
             self.llvm_module.add_function(func_type, "__syscall_"+func_name)
 
         # exception handling
+        func_type = lc.Type.function(lc.Type.int(), [lc.Type.pointer(lc.Type.int(8))])
+        function = self.llvm_module.add_function(func_type, "__eh_setjmp")
+        function.add_attribute(lc.ATTR_NO_UNWIND)
+
         func_type = lc.Type.function(lc.Type.pointer(lc.Type.int(8)), [])
         self.llvm_module.add_function(func_type, "__eh_push")
 
@@ -90,11 +94,10 @@ class LinkInterface:
         return r
 
     def build_catch(self, builder):
+        eh_setjmp = self.llvm_module.get_function_named("__eh_setjmp")
         eh_push = self.llvm_module.get_function_named("__eh_push")
-        setjmp = lc.Function.intrinsic(self.llvm_module,
-                                       lc.INTR_EH_SJLJ_SETJMP, [])
         jmpbuf = builder.call(eh_push, [])
-        exception_occured = builder.call(setjmp, [jmpbuf])
+        exception_occured = builder.call(eh_setjmp, [jmpbuf])
         return builder.icmp(lc.ICMP_NE,
                             exception_occured,
                             lc.Constant.int(lc.Type.int(), 0))

soc/runtime/Makefile

@@ -3,7 +3,7 @@ include $(MSCDIR)/software/common.mak
 BOARD=papilio_pro
 SERIAL=/dev/ttyUSB1
 
-OBJECTS=isr.o elf_loader.o exceptions.o services.o corecom_serial.o gpio.o rtio.o dds.o main.o
+OBJECTS=isr.o elf_loader.o exception_jmp.o exceptions.o services.o corecom_serial.o gpio.o rtio.o dds.o main.o
 
 all: runtime.bin
 

soc/runtime/exception_jmp.S

@@ -0,0 +1,41 @@
+.global exception_setjmp
+.type exception_setjmp,@function
+exception_setjmp:
+    l.sw    0(r3), r1
+    l.sw    4(r3), r2
+    l.sw    8(r3), r9
+    l.sw    12(r3), r10
+    l.sw    16(r3), r14
+    l.sw    20(r3), r16
+    l.sw    24(r3), r18
+    l.sw    28(r3), r20
+    l.sw    32(r3), r22
+    l.sw    36(r3), r24
+    l.sw    40(r3), r26
+    l.sw    44(r3), r28
+    l.sw    48(r3), r30
+    l.jr    r9
+    l.ori   r11,r0,0
+
+.global exception_longjmp
+.type   exception_longjmp,@function
+exception_longjmp:
+    l.sfeqi r4, 0
+    l.bnf   1f
+    l.addi  r11, r4, 0
+    l.ori   r11, r0, 1
+1:  l.lwz   r1, 0(r3)
+    l.lwz   r2, 4(r3)
+    l.lwz   r9, 8(r3)
+    l.lwz   r10, 12(r3)
+    l.lwz   r14, 16(r3)
+    l.lwz   r16, 20(r3)
+    l.lwz   r18, 24(r3)
+    l.lwz   r20, 28(r3)
+    l.lwz   r22, 32(r3)
+    l.lwz   r24, 36(r3)
+    l.lwz   r26, 40(r3)
+    l.lwz   r28, 44(r3)
+    l.lwz   r30, 48(r3)
+    l.jr    r9
+    l.nop

soc/runtime/exceptions.c

@@ -1,9 +1,10 @@
 #include "exceptions.h"
+#include "corecom.h"
 
 #define MAX_EXCEPTION_CONTEXTS 64
 
 struct exception_context {
-    void *jb[5];
+    void *jb[13];
 };
 
 static struct exception_context exception_contexts[MAX_EXCEPTION_CONTEXTS];
@@ -29,5 +30,5 @@ int exception_getid(void)
 
 void exception_raise(int id)
 {
-    __builtin_longjmp(exception_contexts[--ec_top].jb, 1);
+    exception_longjmp(exception_contexts[--ec_top].jb, 1);
 }

soc/runtime/exceptions.h

@@ -5,6 +5,9 @@ enum {
 	EID_NOMEM = 0
 };
 
+int exception_setjmp(void *jb) __attribute__((returns_twice));
+void exception_longjmp(void *jb, int val) __attribute__((noreturn));
+
 void *exception_push(void);
 void exception_pop(int levels);
 int exception_getid(void);

soc/runtime/main.c

@@ -77,7 +77,7 @@ static int run_kernel(const char *kernel_name, int *eid)
     }
 
     jb = exception_push();
-    if(__builtin_setjmp(jb)) {
+    if(exception_setjmp(jb)) {
         *eid = exception_getid();
         return KERNEL_RUN_EXCEPTION;
     } else {

soc/runtime/services.c

@@ -21,6 +21,7 @@ static const struct symbol syscalls[] = {
 };
 
 static const struct symbol eh[] = {
+    {"setjmp", exception_setjmp},
     {"push", exception_push},
     {"pop", exception_pop},
     {"getid", exception_getid},