Literal handling improvements (#1202)

* WIP: 64 literal diagnostic and truncation.

* Improve how integer truncation is handled/supported.
Added literal-int64.slang test.
Set a suffix on all literals.
Fixed problem on C++ based targets where l suffix was not the same as int() cast. So on C++ derived emitters, int() is used instead of l suffix to have same behavior across targets.

* Add literal diagnostic testing.

* Allow lexer to lex - in front of literals.

* Fix lexing and converting int literal with -.

* Too large small values of floats become inf.
Handling writing inf types out on different targets.
Add function to deterimine if a float literals kind.

* Roll back the support of lexer lexing negative literals.

* Fixed tests broken because of diagnostics numbers.
Improved _isFinite

* Fix compilation on linux.

* Fix problem with abs on linux - use Math::Abs.

* Fix typo.

* * Improve warnings for float literals zeroed
* Improved 64 bit type documentation
* Handle half
* Improved comments
* Fixed tests broken
* Use capital letters for suffixes.

* Make default behavior on outputting a int literal that is an 'int32_t' is cast (not suffix) to avoid platform inconsistencies.
Improve documentation for 64 bit types.
Make tests cover material in docs.

* Fixed tests.

* Rename FloatKind::Normal -> Finite

* Fix half zero check.

1 files changed, 32 insertions, 0 deletions

diff --git a/source/slang/slang-ir.cpp b/source/slang/slang-ir.cpp
index 4f33e08ee..b121307ee 100644
--- a/source/slang/slang-ir.cpp
+++ b/source/slang/slang-ir.cpp
@@ -1674,6 +1674,38 @@ namespace Slang
         }
     }
 
+    bool IRConstant::isFinite() const
+    {
+        SLANG_ASSERT(op == kIROp_FloatLit);
+        
+        // Lets check we can analyze as double, at least in principal
+        SLANG_COMPILE_TIME_ASSERT(sizeof(IRFloatingPointValue) == sizeof(double));
+        // We are in effect going to type pun (yay!), lets make sure they are the same size
+        SLANG_COMPILE_TIME_ASSERT(sizeof(IRIntegerValue) == sizeof(IRFloatingPointValue));
+
+        const uint64_t i = uint64_t(value.intVal);
+        int e = int(i >> 52) & 0x7ff;
+        return (e != 0x7ff);
+    }
+
+    IRConstant::FloatKind IRConstant::getFloatKind() const
+    {
+        SLANG_ASSERT(op == kIROp_FloatLit);
+
+        const uint64_t i = uint64_t(value.intVal);
+        int e = int(i >> 52) & 0x7ff;
+        if ( e == 0x7ff)
+        {
+            if (i << 12)
+            {
+                return FloatKind::Nan;
+            }
+            // Sign bit (top bit) will indicate positive or negative nan
+            return value.intVal < 0 ? FloatKind::NegativeInfinity : FloatKind::PositiveInfinity;
+        }
+        return FloatKind::Finite;
+    }
+
     bool IRConstant::isValueEqual(IRConstant* rhs)
     {
         // If they are literally the same thing..