[gcc r12-3449] bpf: correct zero_extend output templates

[gcc r12-3449] bpf: correct zero_extend output templates

[David Faust]

https://gcc.gnu.org/g:4f0f696fea17cd91b184181abcf596df0e857304

commit r12-3449-g4f0f696fea17cd91b184181abcf596df0e857304
Author: David Faust <david.faust@oracle.com>
Date:   Fri Aug 20 14:54:42 2021 -0700

    bpf: correct zero_extend output templates
    
    The output templates for zero_extendhidi2 and zero_extendqidi2 could
    lead to incorrect code generation when zero-extending one register into
    another. This patch adds a new output template to the define_insns to
    handle such cases and produce correct asm.
    
    gcc/ChangeLog:
            * config/bpf/bpf.md (zero_extendhidi2): Add new output template
            for register-to-register extensions.
            (zero_extendqidi2): Likewise.

Diff:
---
 gcc/config/bpf/bpf.md | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/gcc/config/bpf/bpf.md b/gcc/config/bpf/bpf.md
index 03830cc250e..c51add728ef 100644
--- a/gcc/config/bpf/bpf.md
+++ b/gcc/config/bpf/bpf.md
@@ -241,22 +241,24 @@
 ;; the ldx{bhwdw} instructions to load the values in registers.
 
 (define_insn "zero_extendhidi2"
-  [(set (match_operand:DI 0 "register_operand" "=r,r")
-	(zero_extend:DI (match_operand:HI 1 "nonimmediate_operand" "r,m")))]
+  [(set (match_operand:DI 0 "register_operand" "=r,r,r")
+	(zero_extend:DI (match_operand:HI 1 "nonimmediate_operand" "0,r,m")))]
   ""
   "@
    and\t%0,0xffff
+   mov\t%0,%1\;and\t%0,0xffff
    ldxh\t%0,%1"
-  [(set_attr "type" "alu,ldx")])
+  [(set_attr "type" "alu,alu,ldx")])
 
 (define_insn "zero_extendqidi2"
-  [(set (match_operand:DI 0 "register_operand" "=r,r")
-	(zero_extend:DI (match_operand:QI 1 "nonimmediate_operand" "r,m")))]
+  [(set (match_operand:DI 0 "register_operand" "=r,r,r")
+	(zero_extend:DI (match_operand:QI 1 "nonimmediate_operand" "0,r,m")))]
   ""
   "@
    and\t%0,0xff
+   mov\t%0,%1\;and\t%0,0xff
    ldxb\t%0,%1"
-  [(set_attr "type" "alu,ldx")])
+  [(set_attr "type" "alu,alu,ldx")])
 
 (define_insn "zero_extendsidi2"
   [(set (match_operand:DI 0 "register_operand" "=r,r")