While working on a new testcase that uses the RTL frontend,
I hit a bug where a (reg ...) that spans multiple hard registers
had REG_NREGS set to 1. This caused various things to misbehave.
For example, if the (reg ...) in question was used as crtl->return_rtx,
only the first register in the group would be marked as live on exit.
Tested on aarch64-linux-gnu and aarch64_be-elf. OK to install?
Richard
gcc/
* read-rtl-function.cc (function_reader::read_rtx_operand_r): Use
hard_regno_nregs to work out REG_NREGS for hard registers.
---
gcc/read-rtl-function.cc | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/gcc/read-rtl-function.cc b/gcc/read-rtl-function.cc
index fb9c9554ea3..1f08c50cc12 100644
--- a/gcc/read-rtl-function.cc
+++ b/gcc/read-rtl-function.cc
@@ -1065,7 +1065,10 @@ function_reader::read_rtx_operand_r (rtx x)
if (regno == -1)
fatal_at (loc, "unrecognized register: '%s'", name.string);
- set_regno_raw (x, regno, 1);
+ int nregs = 1;
+ if (HARD_REGISTER_NUM_P (regno))
+ nregs = hard_regno_nregs (regno, GET_MODE (x));
+ set_regno_raw (x, regno, nregs);
/* Consolidate singletons. */
x = consolidate_singletons (x);
--
2.43.0
