[clang] [llvm] [LLVM][SROA] Teach SROA how to "bitcast" between fixed and scalable vectors. (PR #130973)

[Paul Walker via cfe-commits]

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@@ -26,11 +26,15 @@ typedef vbool64_t fixed_bool64_t __attribute__((riscv_rvv_vector_bits(__riscv_v_
 //
 // CHECK-128-LABEL: @call_bool32_ff(
 // CHECK-128-NEXT:  entry:
+// CHECK-128-NEXT:    [[SAVED_VALUE:%.*]] = alloca <1 x i8>, align 1
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paulwalker-arm wrote:

@nikic - Is the removal a prerequisite of being able to land this PR?

@topperc / @asi-sc - Any objections to the PR being reverted? Fully or Partly?

Given the size of the regression (9x) I was hoping to backport this fix to LLVM 20. I guess this might not be possible if that means removing https://github.com/llvm/llvm-project/pull/100110 from LLVM 20 as well? 

https://github.com/llvm/llvm-project/pull/130973