WIP: Add support for the llvm: use scheme

src/libponyc/codegen/genexe.c

@@ -606,7 +606,7 @@ bool genexe(compile_t* c, ast_t* program)
       return false;
   }
 
-  const char* file_o = genobj(c);
+  const char* file_o = genobj(c, program);
 
   if(file_o == NULL)
     return false;

src/libponyc/codegen/genobj.c

@@ -1,7 +1,10 @@
 #include "genobj.h"
+#include "../pkg/program.h"
 #include <llvm-c/BitWriter.h>
+#include <llvm-c/IRReader.h>
+#include <llvm-c/Linker.h>
 
-const char* genobj(compile_t* c)
+const char* genobj(compile_t* c, ast_t* program)
 {
   errors_t* errors = c->opt->check.errors;
 
@@ -48,6 +51,38 @@ const char* genobj(compile_t* c)
     return file_o;
   }
 
+  for(strlist_t* p = program_llvm_irs(program); p != NULL ; p = strlist_next(p))
+  {
+    const char* llvmir = strlist_data(p);
+
+    if(c->opt->verbosity >= VERBOSITY_ALL)
+      fprintf(stderr, "Reading llvm: %s\n", llvmir);
+
+    char* err;
+
+    LLVMMemoryBufferRef buf;
+    if(LLVMCreateMemoryBufferWithContentsOfFile(llvmir, &buf, &err) != 0)
+    {
+      errorf(errors, NULL, "couldn't find LLVMIR at %s: %s", llvmir, err);
+      LLVMDisposeMessage(err);
+      return NULL;
+    }
+
+    LLVMModuleRef mod;
+    if (LLVMParseIRInContext(c->context, buf, &mod, &err) != 0)
+    {
+      errorf(errors, NULL, "couldn't parse LLVMIR at %s: %s", llvmir, err);
+      LLVMDisposeMessage(err);
+      return NULL;
+    }
+
+    if (LLVMLinkModules2(c->module, mod) != 0)
+    {
+      errorf(errors, NULL, "failed to link: %s", llvmir);
+      return NULL;
+    }
+  }
+
   LLVMCodeGenFileType fmt;
   const char* file_o;
 

src/libponyc/codegen/genobj.h

@@ -6,7 +6,7 @@
 
 PONY_EXTERN_C_BEGIN
 
-const char* genobj(compile_t* c);
+const char* genobj(compile_t* c, ast_t* program);
 
 PONY_EXTERN_C_END
 

src/libponyc/pkg/program.c

@@ -16,6 +16,7 @@ typedef struct program_t
   uint32_t next_package_id;
   strlist_t* libpaths;
   strlist_t* libs;
+  strlist_t* llvm_irs;
   size_t lib_args_size;
   size_t lib_args_alloced;
   char* lib_args;
@@ -142,6 +143,41 @@ bool use_library(ast_t* use, const char* locator, ast_t* name,
   return true;
 }
 
+/// Process a "llvm:" scheme use command.
+bool use_llvm(ast_t* use, const char* locator, ast_t* name,
+  pass_opt_t* options)
+{
+  (void)name;
+  (void)options;
+
+  char absolute[FILENAME_MAX];
+  const char* prefix = NULL;
+
+  if(!is_path_absolute(locator)) {
+    ast_t* pkg_ast = ast_nearest(use, TK_PACKAGE);
+    prefix = package_path(pkg_ast);
+  }
+
+  path_cat(prefix, locator, absolute);
+
+  size_t len = strlen(absolute);
+  char* allocated = (char*)ponyint_pool_alloc_size(len + 4); // ".ll\0"
+  memcpy(allocated, absolute, len);
+  allocated[len] = '.';
+  allocated[len + 1] = 'l';
+  allocated[len + 2] = 'l';
+  allocated[len + 3] = '\0';
+  const char* libname = stringtab_consume(allocated, len + 4);
+
+  if(libname == NULL)
+    return false;
+
+  ast_t* p = ast_nearest(use, TK_PROGRAM);
+  program_t* prog = (program_t*)ast_data(p);
+
+  prog->llvm_irs = strlist_append(prog->llvm_irs, libname);
+  return true;
+}
 
 /// Process a "path:" scheme use command.
 bool use_path(ast_t* use, const char* locator, ast_t* name,
@@ -173,6 +209,16 @@ bool use_path(ast_t* use, const char* locator, ast_t* name,
   return true;
 }
 
+strlist_t* program_llvm_irs(ast_t* program)
+{
+  pony_assert(program != NULL);
+  pony_assert(ast_id(program) == TK_PROGRAM);
+
+  program_t* data = (program_t*)ast_data(program);
+  pony_assert(data != NULL);
+
+  return data->llvm_irs;
+}
 
 void program_lib_build_args(ast_t* program, pass_opt_t* opt,
   const char* path_preamble, const char* rpath_preamble,

src/libponyc/pkg/program.h

@@ -19,14 +19,24 @@ void program_free(program_t* program);
 /// The actual AST node passed in may be anywhere in the tree.
 uint32_t program_assign_pkg_id(ast_t* ast);
 
+
 /// Process a "lib:" scheme use command.
 bool use_library(ast_t* use, const char* locator, ast_t* name,
   pass_opt_t* options);
 
+/// Process an "llvm:" scheme use command.
+bool use_llvm(ast_t* use, const char* locator, ast_t* name,
+  pass_opt_t* options);
+
 /// Process a "path:" scheme use command.
 bool use_path(ast_t* use, const char* locator, ast_t* name,
   pass_opt_t* options);
 
+/** Assert that the provided ast_t* and the required field
+ * llvm_irs are not NULL before returning the field
+ */
+strlist_t* program_llvm_irs(ast_t* program);
+
 /** Build the required linker arguments based on the libraries we're using.
  * Once this has been called no more calls to use_library() are permitted.
  */

src/libponyc/pkg/use.c

@@ -34,6 +34,7 @@ static __pony_thread_local use_scheme_t handlers[] =
   {"package:", 8, true, false, use_package},
   {"lib:", 4, false, true, use_library},
   {"path:", 5, false, true, use_path},
+  {"llvm:", 5, false, true, use_llvm},
 
   {"test:", 5, false, false, NULL},  // For testing
   {NULL, 0, false, false, NULL}  // Terminator