[JIT] Be more silent about internal failures

Loudly complaining about internal failures tends to upset some people.

src/jit/compile.c

@@ -123,19 +123,22 @@ MVMJitCode * MVM_jit_compiler_assemble(MVMThreadContext *tc, MVMJitCompiler *cl,
 
    /* compile the function */
     if ((dasm_error = dasm_link(cl, &codesize)) != 0) {
-        fprintf(stderr, "DynASM could not link, error: %d\n", dasm_error);
+        if (tc->instance->jit_debug_enabled)
+            fprintf(stderr, "DynASM could not link, error: %d\n", dasm_error);
         return NULL;
     }
 
     memory = MVM_platform_alloc_pages(codesize, MVM_PAGE_READ|MVM_PAGE_WRITE);
     if ((dasm_error = dasm_encode(cl, memory)) != 0) {
-        fprintf(stderr, "DynASM could not encode, error: %d\n", dasm_error);
+        if (tc->instance->jit_debug_enabled)
+            fprintf(stderr, "DynASM could not encode, error: %d\n", dasm_error);
         return NULL;
     }
 
     /* set memory readable + executable */
     if (!MVM_platform_set_page_mode(memory, codesize, MVM_PAGE_READ|MVM_PAGE_EXEC)) {
-        fprintf(stderr, "Setting jit page executable failed or was denied. deactivating jit.\n");
+        if (tc->instance->jit_debug_enabled)
+            fprintf(stderr, "JIT: Impossible to mark code read/executable");
         /* our caller allocated the compiler and our caller must clean it up */
         tc->instance->jit_enabled = 0;
         return NULL;
@@ -171,8 +174,12 @@ MVMJitCode * MVM_jit_compiler_assemble(MVMThreadContext *tc, MVMJitCompiler *cl,
 
     for (i = 0; i < code->num_labels; i++) {
         MVMint32 offset = dasm_getpclabel(cl, i);
-        if (offset < 0)
-            fprintf(stderr, "JIT ERROR: Negative offset for dynamic label %d\n", i);
+        if (offset < 0) {
+            if (tc->instance->jit_debug_enabled)
+                fprintf(stderr, "JIT ERROR: Negative offset for dynamic label %d\n", i);
+            MVM_jit_code_destroy(tc, code);
+            return NULL;
+        }
         code->labels[i] = memory + offset;
     }
     /* We only ever use one global label, which is the exit label */

src/jit/dump.c

@@ -1,30 +1,22 @@
 #include "moar.h"
 
 void MVM_jit_dump_bytecode(MVMThreadContext *tc, MVMJitCode *code) {
-    /* Filename format: moar-jit-%d.bin. number can consume at most 10
-     * bytes, moar-jit-.bin is 13 bytes, one byte for the zero at the
-     * end, one byte for the directory separator is 25 bytes, plus the
-     * length of the bytecode directory itself */
-    size_t filename_size = strlen(tc->instance->jit_bytecode_dir) + 25;
-    char * filename = MVM_malloc(filename_size);
+    char filename[1024];
     FILE * dump;
-    snprintf(filename, filename_size, "%s/moar-jit-%04d.bin",
+    snprintf(filename, sizeof(filename), "%s/moar-jit-%04d.bin",
              tc->instance->jit_bytecode_dir, code->seq_nr);
     dump = fopen(filename, "w");
     if (dump) {
         fwrite(code->func_ptr, sizeof(char), code->size, dump);
         fclose(dump);
-        if (tc->instance->spesh_log_fh) {
-            fprintf(tc->instance->spesh_log_fh,
-                    "JIT: Dumped bytecode to %s\n\n", filename);
-        }
-    } else {
+        if (MVM_spesh_debug_enabled(tc))
+            MVM_spesh_debug_printf(tc, "JIT: Dumped bytecode to %s\n\n", filename);
+    } else if (tc->instance->jit_debug_enabled) {
         FILE *file = tc->instance->spesh_log_fh ?
             tc->instance->spesh_log_fh : stderr;
         fprintf(file, "JIT ERROR: could not dump bytecode: %s",
                 strerror(errno));
     }
-    MVM_free(filename);
 }