Merge pull request #106 from turbolent/break-data-segment-arrays

turbolent · Oct 14, 2024 · 3b37454 · 3b37454
2 parents 8c0e9dd + a03b8aa
commit 3b37454
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Showing 2 changed files with 33 additions and 11 deletions.
diff --git a/README.md b/README.md
@@ -26,7 +26,7 @@ Working towards [WebAssembly as the Elusive Universal Binary](https://kripken.gi
   - [Sign-extension operators](https://github.com/WebAssembly/sign-extension-ops/blob/master/proposals/sign-extension-ops/Overview.md)
   - [Non-trapping float-to-int conversions](https://github.com/WebAssembly/nontrapping-float-to-int-conversions/blob/main/proposals/nontrapping-float-to-int-conversion/Overview.md)
 - Passes 99.9% of the WebAssembly core semantics test suite
-- Written in C89 and generates C89
+- Written in (mostly) C89 and generates (mostly) C89 (some common extensions are used and not all limits are followed, see e.g. #98)
 - Support for many operating systems (e.g. Mac OS X, Mac OS 9, Haiku, Rhapsody, OPENSTEP, NeXTSTEP, DOS, Windows XP, etc.)
 - Support for many architectures (e.g. x86, ARM, PowerPC, SPARC, PA-RISC, etc.)
 - Support for big-endian systems (e.g. PowerPC, SPARC, PA-RISC, etc.)

diff --git a/w2c2/c.c b/w2c2/c.c
@@ -5105,6 +5105,8 @@ wasmCWriteExports(
     }
 }
 
+#define DATA_SEGMENT_CHUNK_LENGTH 18
+
 /* TODO: add support for multiple modules */
 static
 void
@@ -5121,30 +5123,50 @@ wasmCWriteDataSegments(
             U32 dataSegmentIndex = 0;
             for (; dataSegmentIndex < dataSegmentCount; dataSegmentIndex++) {
                 const WasmDataSegment dataSegment = module->dataSegments.dataSegments[dataSegmentIndex];
+                const size_t byteCount = dataSegment.bytes.length;
 
                 fputs("const U8 ", file);
                 /* TODO: add support for multiple modules */
                 wasmCWriteFileDataSegmentName(file, dataSegmentIndex);
                 if (pretty) {
-                    fputs("[] = {\n", file);
+                    fputs("[] = {", file);
                 } else {
-                    fputs("[]={\n", file);
+                    fputs("[]={", file);
                 }
-                if (pretty) {
-                    fputs(indentation, file);
+                if (byteCount > DATA_SEGMENT_CHUNK_LENGTH) {
+                    fputc('\n', file);
+                    if (pretty) {
+                        fputs(indentation, file);
+                    }
                 }
                 {
                     U32 byteIndex = 0;
-                    for (; byteIndex < dataSegment.bytes.length; byteIndex++) {
-                        fprintf(file, "0x%x", dataSegment.bytes.data[byteIndex]);
-                        if (pretty) {
-                            fputs(", ", file);
+                    for (; byteIndex < byteCount; byteIndex++) {
+                        U8 value = dataSegment.bytes.data[byteIndex];
+                        if (byteIndex > 0) {
+                            if (pretty) {
+                                fputs(", ", file);
+                            } else {
+                                fputc(',', file);
+                            }
+                            if (byteIndex % DATA_SEGMENT_CHUNK_LENGTH == 0) {
+                                fputs("\n", file);
+                                if (pretty) {
+                                    fputs(indentation, file);
+                                }
+                            }
+                        }
+                        if (value < 10) {
+                            fprintf(file, "%u", value);
                         } else {
-                            fputc(',', file);
+                            fprintf(file, "0x%x", value);
                         }
                     }
                 }
-                fputs("\n};\n\n", file);
+                if (byteCount > DATA_SEGMENT_CHUNK_LENGTH) {
+                    fputc('\n', file);
+                }
+                fputs("};\n\n", file);
             }
             break;
         }