[llvm] [X86][GlobalISel] Enable G_SDIV/G_UDIV/G_SREM/G_UREM (PR #81615)

[Craig Topper via llvm-commits]

topperc wrote:

> One of the nice features of GlobalIsel is that you can test passes in isolation. Why did the mir tests did not reveal the bug? End-to-end tests are a SelectionDag feature.

They show the SUBREG_TO_REG, but SUBREG_TO_REG is often misunderstood and there's nothing that can check that is correctly used.

https://github.com/llvm/llvm-project/pull/81615