[Bug rtl-optimization/113597] [14 Regression] aarch64: Significant code quality regression since r14-8346-ga98d5130a6dcff

[acoplan at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113597

--- Comment #6 from Alex Coplan <acoplan at gcc dot gnu.org> ---
Looking at the dump files, the first difference seems to be in 292r.dse1:

     8: NOTE_INSN_BASIC_BLOCK 2
     2: r116:SI=zero_extend(x0:HI)
       REG_DEAD x0:HI
@@ -178,7 +161,26 @@
     5: NOTE_INSN_FUNCTION_BEG
    10: r119:DI=sfp:DI-0x200
    12: r121:V16QI=const_vector
+   13: [r119:DI]=unspec[r121:V16QI,r121:V16QI] 38
+   14: [r119:DI+0x20]=unspec[r121:V16QI,r121:V16QI] 38
+   15: [r119:DI+0x40]=unspec[r121:V16QI,r121:V16QI] 38
+   16: [r119:DI+0x60]=unspec[r121:V16QI,r121:V16QI] 38
+   17: [r119:DI+0x80]=unspec[r121:V16QI,r121:V16QI] 38
+   18: [r119:DI+0xa0]=unspec[r121:V16QI,r121:V16QI] 38
+   19: [r119:DI+0xc0]=unspec[r121:V16QI,r121:V16QI] 38
+   20: [r119:DI+0xe0]=unspec[r121:V16QI,r121:V16QI] 38
+      REG_DEAD r119:DI
    21: r122:DI=sfp:DI-0x100
+   24: [r122:DI]=unspec[r121:V16QI,r121:V16QI] 38
+   25: [r122:DI+0x20]=unspec[r121:V16QI,r121:V16QI] 38
+   26: [r122:DI+0x40]=unspec[r121:V16QI,r121:V16QI] 38
+   27: [r122:DI+0x60]=unspec[r121:V16QI,r121:V16QI] 38
+   28: [r122:DI+0x80]=unspec[r121:V16QI,r121:V16QI] 38
+   29: [r122:DI+0xa0]=unspec[r121:V16QI,r121:V16QI] 38
+   30: [r122:DI+0xc0]=unspec[r121:V16QI,r121:V16QI] 38
+   31: [r122:DI+0xe0]=unspec[r121:V16QI,r121:V16QI] 38
+      REG_DEAD r122:DI
+      REG_DEAD r121:V16QI
     6: r100:V4SF=const_vector
     7: r106:SI=0
    32: cc:CC=cmp(r116:SI,0)
@@ -254,6 +256,7 @@
    73: r100:V4SF={r147:V4SF*r147:V4SF+r115:V4SF}
       REG_DEAD r147:V4SF
       REG_DEAD r115:V4SF
+   74: [sfp:DI-0x200]=r100:V4SF
    75: r148:SI=r106:SI+0x2
       REG_DEAD r106:SI
    76: r106:SI=zero_extend(r148:SI#0)

(the unspec 38s are store pairs).