This is the next piece towards a fix for (the x86_64 ABI issues affecting) PR 88873. This patch generalizes the recent tweak to ix86_expand_move for setting the highpart of a TImode reg from a DImode source using *insvti_highpart_1, to handle both DImode and DFmode sources, and also use the recently added *insvti_lowpart_1 for setting the lowpart. Although this is another intermediate step (not yet a fix), towards enabling *insvti and *concat* patterns to be candidates for TImode STV (by using V2DI/V2DF instructions), it already improves things a little. For the test case from PR 88873 typedef struct { double x, y; } s_t; typedef double v2df __attribute__ ((vector_size (2 * sizeof(double)))); s_t foo (s_t a, s_t b, s_t c) { return (s_t) { fma(a.x, b.x, c.x), fma (a.y, b.y, c.y) }; } With -O2 -march=cascadelake, GCC currently generates: Before (29 instructions): vmovq %xmm2, -56(%rsp) movq -56(%rsp), %rdx vmovq %xmm4, -40(%rsp) movq $0, -48(%rsp) movq %rdx, -56(%rsp) movq -40(%rsp), %rdx vmovq %xmm0, -24(%rsp) movq %rdx, -40(%rsp) movq -24(%rsp), %rsi movq -56(%rsp), %rax movq $0, -32(%rsp) vmovq %xmm3, -48(%rsp) movq -48(%rsp), %rcx vmovq %xmm5, -32(%rsp) vmovq %rax, %xmm6 movq -40(%rsp), %rax movq $0, -16(%rsp) movq %rsi, -24(%rsp) movq -32(%rsp), %rsi vpinsrq $1, %rcx, %xmm6, %xmm6 vmovq %rax, %xmm7 vmovq %xmm1, -16(%rsp) vmovapd %xmm6, %xmm3 vpinsrq $1, %rsi, %xmm7, %xmm7 vfmadd132pd -24(%rsp), %xmm7, %xmm3 vmovapd %xmm3, -56(%rsp) vmovsd -48(%rsp), %xmm1 vmovsd -56(%rsp), %xmm0 ret After (20 instructions): vmovq %xmm2, -56(%rsp) movq -56(%rsp), %rax vmovq %xmm3, -48(%rsp) vmovq %xmm4, -40(%rsp) movq -48(%rsp), %rcx vmovq %xmm5, -32(%rsp) vmovq %rax, %xmm6 movq -40(%rsp), %rax movq -32(%rsp), %rsi vpinsrq $1, %rcx, %xmm6, %xmm6 vmovq %xmm0, -24(%rsp) vmovq %rax, %xmm7 vmovq %xmm1, -16(%rsp) vmovapd %xmm6, %xmm2 vpinsrq $1, %rsi, %xmm7, %xmm7 vfmadd132pd -24(%rsp), %xmm7, %xmm2 vmovapd %xmm2, -56(%rsp) vmovsd -48(%rsp), %xmm1 vmovsd -56(%rsp), %xmm0 ret This patch has been tested on x86_64-pc-linux-gnu with make bootstrap and make -k check, both with and without --target_board=unix{-m32} with no new failures. No testcase yet, as the above code will hopefully change dramatically with the next pieces. Ok for mainline? 2023-07-13 Roger Sayle gcc/ChangeLog * config/i386/i386-expand.cc (ix86_expand_move): Generalize special case inserting of 64-bit values into a TImode register, to handle both DImode and DFmode using either *insvti_lowpart_1 or *isnvti_highpart_1. Thanks again, Roger --