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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hello folks,<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>Some ARMv7-A processor implementations (e.g, Qualcomm 8960, ARM Cortex-A5) support fused multiply add/subtract instructions (VFMA/VFMS) which have lower latency and greater accuracy than the chained multiply add/subtract instructions (VMLA/VMLS).<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>I have modified LLVM ARM target files to add support for fused multiply add/subtract instructions. A processor definition just needs to add ‘FeatureNEONVFP4’ to its list of subtarget features in order to enable the generation of fused multiply add/subtract instructions.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The patch is attached for your review, if you have interest in merging this change into LLVM.<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal><b>Patch details:</b><o:p></o:p></p><p class=MsoNormal>fusedMACpatch.diff<o:p></o:p></p><p class=MsoNormal>Changes to ARM-specific files to support fused multiply add/subtract instructions.<o:p></o:p></p><p class=MsoNormal>Associated fused multiply add/subtract instructions with processor subtarget feature ‘FeatureNEONVFP4’ and with the assembler feature flag ‘neon-vfpv4’ .<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>fusedMAC.ll<o:p></o:p></p><p class=MsoNormal>Test to check for generated fused multiply accumulate and subtract instructions.<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>failures.txt<o:p></o:p></p><p class=MsoNormal>Failure report from running llvm/test and projects/test-suite on ARM.<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal>Thank you,<o:p></o:p></p><p class=MsoNormal>Ana.<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>--<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>Qualcomm Innovation Center, Inc is a member of Code Aurora Forum<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>