[llvm] [Offload] Erase entries from JIT cache when program is destroyed (PR #148847)

[Ross Brunton via llvm-commits]

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@@ -285,8 +285,8 @@ JITEngine::compile(const __tgt_device_image &Image,
 
   // Check if we JITed this image for the given compute unit kind before.
   ComputeUnitInfo &CUI = ComputeUnitMap[ComputeUnitKind];
-  if (__tgt_device_image *JITedImage = CUI.TgtImageMap.lookup(&Image))
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RossBrunton wrote:

I'm still unsure of why we need to keep them around after the backing image has been dropped. I can't see the user constantly recreating the same buffer many times with the same contents and expecting high performance.

https://github.com/llvm/llvm-project/pull/148847