[Mlir-commits] [mlir] [mlir][complex] Fix exp special values for infinite real part (PR #232791)

[Chang Yong Lik]

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@@ -361,6 +361,26 @@ struct ExpOpConversion : public OpConversionPattern<complex::ExpOp> {
         arith::SelectOp::create(b, expIsInf, imagOverflow, imagNormal);
     Value resultImag = arith::SelectOp::create(b, yIsZero, zero, imagNonZero);
 
+    // When x is +-inf and y is +-inf or NaN, exp(x) * cos(y) is inf * NaN or
+    // 0 * NaN. C99 Annex G gives exp(-inf + I*y) = +-0 +- 0*I and
+    // exp(+inf + I*y) = +-inf + NaN*I for these y.
+    if (!arith::bitEnumContainsAll(fmf, arith::FastMathFlags::ninf)) {
+      Value absX = math::AbsFOp::create(b, x);
+      Value absY = math::AbsFOp::create(b, y);
+      Value negInf = arith::ConstantOp::create(
+          b, ET, b.getFloatAttr(ET, APFloat::getInf(floatSemantics, true)));
+      Value yIsNotFinite =
+          arith::CmpFOp::create(b, arith::CmpFPredicate::UGE, absY, inf);
+      Value xIsInf =
+          arith::CmpFOp::create(b, arith::CmpFPredicate::OEQ, absX, inf);
+      Value xIsNegInf =
+          arith::CmpFOp::create(b, arith::CmpFPredicate::OEQ, x, negInf);
+      Value useExpX = arith::AndIOp::create(b, xIsInf, yIsNotFinite);
+      Value useZeroImag = arith::AndIOp::create(b, xIsNegInf, yIsNotFinite);
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ahlag wrote:

Done in f168710, thanks.

https://github.com/llvm/llvm-project/pull/232791