Replace simm32 extractor with i32_from_iconst
#8842
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This commit removes the `simm32` extractor from lowerings as it's not as useful as it was when it was first introduced. Nowadays an `Imm64` needs to be interpreted with the type known as well to understand whether bits being masked off is significant or not. The old `simm32` extractor only took `Imm64` meaning that it was unable to do this and wouldn't match negative numbers. This is because the high 32 bits of `Imm64` were always zero and `simm64` would take the `i64` value from `Imm64` and try to convert it to an `i32`. This commit replaces `simm32`, and uses of it, with a new extractor `i32_from_iconst`. This matches the preexisting `i64_from_iconst` and is able to take the type of the value into account and produce a correctly sign-extended value. cc bytecodealliance#8706
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Jun 19, 2024
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This commit removes the
simm32extractor from lowerings as it's not as useful as it was when it was first introduced. Nowadays anImm64needs to be interpreted with the type known as well to understand whether bits being masked off is significant or not. The oldsimm32extractor only tookImm64meaning that it was unable to do this and wouldn't match negative numbers. This is because the high 32 bits ofImm64were always zero andsimm64would take thei64value fromImm64and try to convert it to ani32.This commit replaces
simm32, and uses of it, with a new extractori32_from_iconst. This matches the preexistingi64_from_iconstand is able to take the type of the value into account and produce a correctly sign-extended value.cc #8706