[libclc] [libclc] Produce subnormal results for fmod on FP32 (PR #215768)

[Wenju He via cfe-commits]

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@@ -6,17 +6,23 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include <clc/clc_convert.h>
-#include <clc/integer/clc_clz.h>
-#include <clc/internal/clc.h>
-#include <clc/math/clc_floor.h>
-#include <clc/math/clc_fma.h>
-#include <clc/math/clc_ldexp.h>
-#include <clc/math/clc_trunc.h>
-#include <clc/math/math.h>
-#include <clc/shared/clc_max.h>
-
-_CLC_DEF _CLC_OVERLOAD float __clc_fmod(float x, float y) {
+#include "clc/clc_convert.h"
+#include "clc/integer/clc_clz.h"
+#include "clc/internal/clc.h"
+#include "clc/math/clc_floor.h"
+#include "clc/math/clc_fma.h"
+#include "clc/math/clc_ldexp.h"
+#include "clc/math/clc_subnormal_config.h"
+#include "clc/math/clc_trunc.h"
+#include "clc/math/math.h"
+#include "clc/shared/clc_max.h"
+
+// Core fmod reduction. Assumes x and y are finite, non-zero and normal (the
+// exponent field is reconstructed from ex/ey and the result is rescaled with
+// as_float(ey << 23), which is only correct for normal operands and would
+// flush a subnormal result to zero). Callers must normalize subnormal inputs
+// before calling and handle NaN/Inf/zero edge cases.
+_CLC_DEF _CLC_OVERLOAD float __clc_fmod_impl(float x, float y) {
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wenju-he wrote:

change `_CLC_DEF _CLC_OVERLOAD` to `static` since this is an internal helper.

https://github.com/llvm/llvm-project/pull/215768