Add support for 1-wide scalar target.

Issue #40.

Makefile

@@ -72,7 +72,7 @@ CXX_SRC=ast.cpp builtins.cpp cbackend.cpp ctx.cpp decl.cpp expr.cpp func.cpp \
 HEADERS=ast.h builtins.h ctx.h decl.h expr.h func.h ispc.h llvmutil.h module.h \
 	opt.h stmt.h sym.h type.h util.h
 TARGETS=avx1 avx1-x2 avx2 avx2-x2 sse2 sse2-x2 sse4 sse4-x2 generic-4 generic-8 \
-	generic-16
+	generic-16 generic-1
 BUILTINS_SRC=$(addprefix builtins/target-, $(addsuffix .ll, $(TARGETS))) \
 	builtins/dispatch.ll
 BUILTINS_OBJS=$(addprefix builtins-, $(notdir $(BUILTINS_SRC:.ll=.o))) \

builtins.cpp

@@ -799,6 +799,13 @@ DefineStdlib(SymbolTable *symbolTable, llvm::LLVMContext *ctx, llvm::Module *mod
                                builtins_bitcode_generic_16_length, 
                                module, symbolTable);
             break;
+	case 1:
+            extern unsigned char builtins_bitcode_generic_1[];
+            extern int builtins_bitcode_generic_1_length;
+            AddBitcodeToModule(builtins_bitcode_generic_1, 
+                               builtins_bitcode_generic_1_length, 
+                               module, symbolTable);
+            break;
         default:
             FATAL("logic error in DefineStdlib");
         }
@@ -834,7 +841,7 @@ DefineStdlib(SymbolTable *symbolTable, llvm::LLVMContext *ctx, llvm::Module *mod
         // If the user wants the standard library to be included, parse the
         // serialized version of the stdlib.ispc file to get its
         // definitions added.
-        if (g->target.isa == Target::GENERIC) {
+      if (g->target.isa == Target::GENERIC&&g->target.vectorWidth!=1) { // 1 wide uses x86 stdlib
             extern char stdlib_generic_code[];
             yy_scan_string(stdlib_generic_code);
             yyparse();

ispc.cpp

@@ -185,6 +185,14 @@ Target::GetTarget(const char *arch, const char *cpu, const char *isa,
         t->allOffMaskIsSafe = true;
         t->maskBitCount = 1;
     }
+    else if (!strcasecmp(isa, "generic-1")) {
+        t->isa = Target::GENERIC;
+        t->nativeVectorWidth = 1;
+        t->vectorWidth = 1;
+        t->maskingIsFree = false;
+        t->allOffMaskIsSafe = false;
+        t->maskBitCount = 32;
+    }
 #if defined(LLVM_3_0) || defined(LLVM_3_0svn) || defined(LLVM_3_1svn)
     else if (!strcasecmp(isa, "avx")) {
         t->isa = Target::AVX;
@@ -270,7 +278,7 @@ Target::SupportedTargetISAs() {
 #ifdef LLVM_3_1svn
         ", avx2, avx2-x2"
 #endif // LLVM_3_1svn
-        ", generic-4, generic-8, generic-16";
+        ", generic-4, generic-8, generic-16, generic-1";
 }
 
 

parse.yy

@@ -1659,7 +1659,7 @@ lAddFunctionParams(Declarator *decl) {
 
 /** Add a symbol for the built-in mask variable to the symbol table */
 static void lAddMaskToSymbolTable(SourcePos pos) {
-    const Type *t = g->target.isa == Target::GENERIC ?
+    const Type *t = g->target.maskBitCount == 1 ?
         AtomicType::VaryingConstBool : AtomicType::VaryingConstUInt32;
     Symbol *maskSymbol = new Symbol("__mask", pos, t);
     m->symbolTable->AddVariable(maskSymbol);