Fix rawBufferVectorLoad/Store to widen min precision types to 32-bit#8274
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alsepkow wants to merge 1 commit intomicrosoft:mainfrom
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Fix rawBufferVectorLoad/Store to widen min precision types to 32-bit#8274alsepkow wants to merge 1 commit intomicrosoft:mainfrom
alsepkow wants to merge 1 commit intomicrosoft:mainfrom
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RawBufferVectorLoad/Store for min precision types (min16int, min16uint, min16float) was emitting i16/f16 vector operations (e.g., v3i16) which causes WARP and potentially other drivers to load/store 2 bytes per element instead of 4. This mismatches the buffer layout when the CPU writes 32-bit values. Pre-SM6.9 RawBufferLoad correctly handles this by loading as i32/f32 and truncating. Apply the same pattern for SM6.9 vector variants: - RawBufferVectorLoad: load as v_i32/v_f32, then trunc to i16/half - RawBufferVectorStore: sext/fpext to i32/f32, then store as v_i32/v_f32 This matches the existing bool widening pattern already in TranslateBufLoad. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Summary
Fixes rawBufferVectorLoad/Store to use 32-bit element types (i32/f32) for min precision types (min16int, min16uint, min16float) instead of 16-bit (i16/f16). This matches how pre-SM6.9 RawBufferLoad handles min precision.
Resolves #8273
Root Cause
\TranslateBufLoad\ in \HLOperationLower.cpp\ creates the vector type directly from the min precision element type (i16/f16) without widening to i32/f32. This causes WARP (and potentially other drivers) to load/store 2 bytes per element instead of 4, mismatching the buffer layout.
Fix
Apply the same widening pattern used for bool types:
awBufferVectorLoad.v_i32/v_f32, then \ runc/\ ptrunc\ back
awBufferVectorStore.v_i32/v_f32\
Testing
Added FileCheck test verifying all 3 min precision types produce i32/f32 vector load/store ops.
Co-authored-by: Copilot 223556219+Copilot@users.noreply.github.com