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<span>Hi,</span></div>
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<span>I'm new to LLVM and I ran llc with -print-before-all and I can see that the IR is already wrong before Expand ISel Pseudo-instructions. The MOVE instruction moves a register to itself and shouldn't be there. How do you debug something like this?
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<span style="font-family:"Courier New",monospace">*** IR Dump After Module Verifier ***</span><span><br>
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<div><span style="font-family:"Courier New",monospace">define i32* @_Z9test_mathv() #0 {</span><br>
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<div><span style="font-family:"Courier New",monospace"> %a = alloca i32, align 4</span><br>
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<div><span style="font-family:"Courier New",monospace"> ret i32* %a</span><br>
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<div><span style="font-family:"Courier New",monospace">}</span><br>
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<div><span style="font-family:"Courier New",monospace"># *** IR Dump Before Expand ISel Pseudo-instructions ***:</span><br>
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<div><span style="font-family:"Courier New",monospace"># Machine code for function _Z9test_mathv: Properties: <></span><br>
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<div><span style="font-family:"Courier New",monospace">Frame Objects:</span><br>
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<div><span style="font-family:"Courier New",monospace"> fi#0: size=4, align=4, at location [SP]</span><br>
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<div><span style="font-family:"Courier New",monospace">BB#0: derived from LLVM BB %0</span><br>
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<div><span style="font-family:"Courier New",monospace"> <b>%vreg0<def> = MOVE %vreg0;</b> CPURegs:%vreg0</span><br>
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<div><span style="font-family:"Courier New",monospace"> %R4<def> = COPY %vreg0; CPURegs:%vreg0</span><br>
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<span style="font-family:"Courier New",monospace"> JLR %R4</span></div>
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<span style="font-family:Calibri,Helvetica,sans-serif">Thanks</span><br>
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