Add the smaller magnitude component first.

rhettinger · rhettinger · commit d274325737e3 · 2023-01-06T13:24:16.000-06:00
diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c
@@ -2900,8 +2900,8 @@ static inline DoubleLength
 dl_fma(DoubleLength total, double p, double q)
 {
     DoubleLength product = dl_mul(p, q);
-    total = dl_add(total, product.hi);
-    return dl_add(total, product.lo);
+    total = dl_add(total, product.lo);
+    return  dl_add(total, product.hi);
 }
 
 static inline double

Original file line number	Diff line number	Diff line change
`@@ -2900,8 +2900,8 @@ static inline DoubleLength`
`2900`	`2900`	`dl_fma(DoubleLength total, double p, double q)`
`2901`	`2901`	`{`
`2902`	`2902`	`DoubleLength product = dl_mul(p, q);`
`2903`		`- total = dl_add(total, product.hi);`
`2904`		`- return dl_add(total, product.lo);`
	`2903`	`+ total = dl_add(total, product.lo);`
	`2904`	`+ return dl_add(total, product.hi);`
`2905`	`2905`	`}`
`2906`	`2906`
`2907`	`2907`	`static inline double`