Add some comments for TableGen's NeonEmitter.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120596 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bob Wilson 2010-12-01 19:49:56 +00:00
parent 5b7fe5920d
commit 95148ad023
2 changed files with 16 additions and 11 deletions

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@ -293,9 +293,9 @@ static std::string BuiltinTypeString(const char mod, StringRef typestr,
bool pntr = false;
if (mod == 'v')
return "v";
return "v"; // void
if (mod == 'i')
return "i";
return "i"; // int
// base type to get the type string for.
char type = ClassifyType(typestr, quad, poly, usgn);
@ -303,11 +303,13 @@ static std::string BuiltinTypeString(const char mod, StringRef typestr,
// Based on the modifying character, change the type and width if necessary.
type = ModType(mod, type, quad, poly, usgn, scal, cnst, pntr);
// All pointers are void* pointers. Change type to 'v' now.
if (pntr) {
usgn = false;
poly = false;
type = 'v';
}
// Treat half-float ('h') types as unsigned short ('s') types.
if (type == 'h') {
type = 's';
usgn = true;
@ -320,7 +322,7 @@ static std::string BuiltinTypeString(const char mod, StringRef typestr,
if (usgn)
s.push_back('U');
if (type == 'l')
if (type == 'l') // 64-bit long
s += "LLi";
else
s.push_back(type);
@ -338,7 +340,7 @@ static std::string BuiltinTypeString(const char mod, StringRef typestr,
// fashion, storing them to a pointer arg.
if (ret) {
if (mod >= '2' && mod <= '4')
return "vv*";
return "vv*"; // void result with void* first argument
if (mod == 'f' || (ck != ClassB && type == 'f'))
return quad ? "V4f" : "V2f";
if (ck != ClassB && type == 's')
@ -711,9 +713,9 @@ static std::string GenBuiltin(const std::string &name, const std::string &proto,
// the immediate passed by the user.
bool define = proto.find('i') != std::string::npos;
// If all types are the same size, bitcasting the args will take care
// of arg checking. The actual signedness etc. will be taken care of with
// special enums.
// Check if the prototype has a scalar operand with the type of the vector
// elements. If not, bitcasting the args will take care of arg checking.
// The actual signedness etc. will be taken care of with special enums.
if (proto.find('s') == std::string::npos)
ck = ClassB;
@ -736,6 +738,7 @@ static std::string GenBuiltin(const std::string &name, const std::string &proto,
s += "__builtin_neon_";
if (splat) {
// Call the non-splat builtin: chop off the "_n" suffix from the name.
std::string vname(name, 0, name.size()-2);
s += MangleName(vname, typestr, ck);
} else {
@ -750,6 +753,8 @@ static std::string GenBuiltin(const std::string &name, const std::string &proto,
for (unsigned i = 1, e = proto.size(); i != e; ++i, ++arg) {
std::string args = std::string(&arg, 1);
// Wrap macro arguments in parenthesis.
if (define)
args = "(" + args + ")";

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@ -56,10 +56,10 @@ enum OpKind {
enum ClassKind {
ClassNone,
ClassI,
ClassS,
ClassW,
ClassB
ClassI, // generic integer instruction, e.g., "i8" suffix
ClassS, // signed/unsigned/poly, e.g., "s8", "u8" or "p8" suffix
ClassW, // width-specific instruction, e.g., "8" suffix
ClassB // bitcast arguments with enum argument to specify type
};
namespace llvm {