clang is suboptimal for `x / sqrt(y / z)` with fast-math

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Test case:
https://godbolt.org/z/joGE9G4KM

#include<math.h>

double test_sqrt1(double x, double y, double z) { 
  return x / sqrt(y / z); 
}

double test_sqrt2(double x, double y, double z) { 
  return x * sqrt(z / y); 
}

My expectation is that the output of test_sqrt1 will be the same as test_sqrt2. The same transformatin is true not only for sqrt but also for cbrt.

[zjaffal]

looking into this,
For this I guess the assumption is that both the first and second div have the following are true?

• hasAllowReassoc
• hasAllowReciprocal

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The patch was reverted by f022aaf.

[dtcxzyw]

The patch was reverted by f022aaf.

cc @arsenm

[zjaffal]

i will take a look at why it was reverted

[zjaffal]

fix #81970

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The fix has been merged. I will close this issue.