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    <head>
      <base href="https://bugs.llvm.org/">
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - InstCombine leaves extra call to sqrtf from pow transform"
   href="https://bugs.llvm.org/show_bug.cgi?id=47613">47613</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>InstCombine leaves extra call to sqrtf from pow transform
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>libraries
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>trunk
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>All
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>All
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Transformation Utilities
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>unassignedbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>hstong@ca.ibm.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org, spatel+llvm@rotateright.com
          </td>
        </tr></table>
      <p>
        <div>
        <pre>As noted in the review of D88066, there is an extra `sqrtf` call formed from
the call to `pow` in `shrink_pow_libcall_half` (below, extracted from
`llvm/test/Transforms/InstCombine/pow-4.ll`).

### SOURCE (<stdin>):
declare double @pow(double, double)

define float @shrink_pow_libcall_half(float %x) {
  %dx = fpext float %x to double
  %call = call fast double @pow(double %dx, double 0.5)
  %fr = fptrunc double %call to float
  ret float %fr
}


### LLVM INVOCATION:
opt -instcombine -S


### ACTUAL OUTPUT:
; ModuleID = '<stdin>'
source_filename = "<stdin>"

declare double @pow(double, double)

define float @shrink_pow_libcall_half(float %x) {
  %sqrtf = call fast float @sqrtf(float %x)
  %sqrtf1 = call fast float @sqrtf(float %x)
  ret float %sqrtf1
}

declare float @powf(float, float)

declare double @sqrt(double)

declare float @sqrtf(float)


### EXPECTED OUTPUT:
(only one call to `sqrtf`)


### LLVM VERSION INFO (opt --version):
LLVM (<a href="http://llvm.org/">http://llvm.org/</a>):
  LLVM version 12.0.0git
  Optimized build.
  Default target: x86_64-unknown-linux-gnu
  Host CPU: sandybridge


### LLVM VERSION INFO:
<a href="https://github.com/llvm/llvm-project.git">https://github.com/llvm/llvm-project.git</a>
a8b8a9374a3c555ac8528fc37b92935554083b9f</pre>
        </div>
      </p>


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