The input constraint for the %vmovddup alternative was wrong, as the
upper 16 XMM registers require AVX512VL to be used with this insn. To
compensate, introduce a new alternative permitting all 32 registers, by
broadcasting to the full 512 bits in that case if AVX512VL is not
available.
gcc/
* config/i386/sse.md (vec_dupv2di): Correct %vmovddup input
constraint. Add new AVX512F alternative.
---
Strictly speaking the new alternative could be enabled from AVX2
onwards, but vmovddup can frequently be a shorter encoding (VEX2 vs
VEX3).
It was suggested that the previously flawed %vmovddup alternative could
use "xm" as source constraint. But then its destination would better also
use "x", I think?
---
v2: Use "* return ..." form. Set "mode" to XI for new alternative
without AVX512VL.
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -26033,19 +26033,35 @@
(symbol_ref "true")))])
(define_insn "*vec_dupv2di"
- [(set (match_operand:V2DI 0 "register_operand" "=x,v,v,x")
+ [(set (match_operand:V2DI 0 "register_operand" "=x,v,v,v,x")
(vec_duplicate:V2DI
- (match_operand:DI 1 "nonimmediate_operand" " 0,Yv,vm,0")))]
+ (match_operand:DI 1 "nonimmediate_operand" " 0,Yv,vm,Yvm,0")))]
"TARGET_SSE"
"@
punpcklqdq\t%0, %0
vpunpcklqdq\t{%d1, %0|%0, %d1}
+ * return TARGET_AVX512VL ? \"vpbroadcastq\t{%1, %0|%0, %1}\" :
\"vpbroadcastq\t{%1, %g0|%g0, %1}\";
%vmovddup\t{%1, %0|%0, %1}
movlhps\t%0, %0"
- [(set_attr "isa" "sse2_noavx,avx,sse3,noavx")
- (set_attr "type" "sselog1,sselog1,sselog1,ssemov")
- (set_attr "prefix" "orig,maybe_evex,maybe_vex,orig")
- (set_attr "mode" "TI,TI,DF,V4SF")])
+ [(set_attr "isa" "sse2_noavx,avx,avx512f,sse3,noavx")
+ (set_attr "type" "sselog1,sselog1,ssemov,sselog1,ssemov")
+ (set_attr "prefix" "orig,maybe_evex,evex,maybe_vex,orig")
+ (set (attr "mode")
+ (cond [(and (eq_attr "alternative" "2")
+ (match_test "!TARGET_AVX512VL"))
+ (const_string "XI")
+ (eq_attr "alternative" "3")
+ (const_string "DF")
+ (eq_attr "alternative" "4")
+ (const_string "V4SF")
+ ]
+ (const_string "TI")))
+ (set (attr "enabled")
+ (if_then_else
+ (eq_attr "alternative" "2")
+ (symbol_ref "TARGET_AVX512VL
+ || (TARGET_AVX512F && !TARGET_PREFER_AVX256)")
+ (const_string "*")))])
(define_insn "avx2_vbroadcasti128_<mode>"
[(set (match_operand:VI_256 0 "register_operand" "=x,v,v")
