Add support for a "strict" floating-point mode (#709)

This change adds an API function and command line options for controlling the default floating-point behavior for a target, with options for "fast" and "precise" computation.
The "precise" option gets mapped to the "IEEE strictness" mode in `fxc` and `dxc` (there is currently no equivalent option for glslang that I could find).

1 files changed, 19 insertions, 0 deletions

diff --git a/slang.h b/slang.h
index 83aece07f..f774ab323 100644
--- a/slang.h
+++ b/slang.h
@@ -451,6 +451,17 @@ extern "C"
     };
 
     /*!
+    @brief Options to control floating-point precision guarantees for a target.
+    */
+    typedef unsigned int SlangFloatingPointMode;
+    enum
+    {
+        SLANG_FLOATING_POINT_MODE_DEFAULT = 0,
+        SLANG_FLOATING_POINT_MODE_FAST,
+        SLANG_FLOATING_POINT_MODE_PRECISE,
+    };
+
+    /*!
     @brief Options to control emission of `#line` directives
     */
     typedef unsigned int SlangLineDirectiveMode;
@@ -877,6 +888,14 @@ extern "C"
         int                     targetIndex,
         SlangTargetFlags        flags);
 
+    /*!
+    @brief Set the floating point mode (e.g., precise or fast) to use a target.
+    */
+    SLANG_API void spSetTargetFloatingPointMode(
+        SlangCompileRequest*    request,
+        int                     targetIndex,
+        SlangFloatingPointMode  mode);
+
     /* DEPRECATED: use `spSetMatrixLayoutMode` instead. */
     SLANG_API void spSetTargetMatrixLayoutMode(
         SlangCompileRequest*    request,