An Introduction to RISC-V Vector Programming with C Intrinsics

on YouTube ↗10m

" summary

Overview of the RISC-V vector ISA and a C intrinsics proposal on GitHub with concrete examples using an Andes NX27V core and an LLVM-based toolchain. Demonstrates vsetvl/vl to select runtime vector length, vle/vse loads/stores, masking and LMUL widening (e.g., LMUL=2), a vectorized loop that returns VL for leftovers, and compiler actions that emit v-instructions and remove redundant vsetvl. Claims conformance to vector spec v0.9 and working codegen on NX27V.

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" chapters (6)

1. 0:00Introduction to Vector Tool
2. 0:21Vector Data and Mask Types
3. 3:41Intrinsic Functions & Overloads
4. 6:09Masked Operations
5. 6:57Vectorization Example
6. 9:09Compiler Support & Conclusion

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