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-rw-r--r--packages/gcc/13.2.0/0015-aarch64-Avoid-a-use-of-callee_offset.patch73
1 files changed, 73 insertions, 0 deletions
diff --git a/packages/gcc/13.2.0/0015-aarch64-Avoid-a-use-of-callee_offset.patch b/packages/gcc/13.2.0/0015-aarch64-Avoid-a-use-of-callee_offset.patch
new file mode 100644
index 00000000..8a30f5a6
--- /dev/null
+++ b/packages/gcc/13.2.0/0015-aarch64-Avoid-a-use-of-callee_offset.patch
@@ -0,0 +1,73 @@
+From 89a9fa287706c5011f61926eaf65e7b996b963a3 Mon Sep 17 00:00:00 2001
+From: Richard Sandiford <richard.sandiford@arm.com>
+Date: Tue, 12 Sep 2023 16:07:12 +0100
+Subject: [PATCH 15/32] aarch64: Avoid a use of callee_offset
+
+When we emit the frame chain, i.e. when we reach Here in this statement
+of aarch64_expand_prologue:
+
+ if (emit_frame_chain)
+ {
+ // Here
+ ...
+ }
+
+the stack is in one of two states:
+
+- We've allocated up to the frame chain, but no more.
+
+- We've allocated the whole frame, and the frame chain is within easy
+ reach of the new SP.
+
+The offset of the frame chain from the current SP is available
+in aarch64_frame as callee_offset. It is also available as the
+chain_offset local variable, where the latter is calculated from other
+data. (However, chain_offset is not always equal to callee_offset when
+!emit_frame_chain, so chain_offset isn't redundant.)
+
+In c600df9a4060da3c6121ff4d0b93f179eafd69d1 I switched to using
+chain_offset for the initialisation of the hard frame pointer:
+
+ aarch64_add_offset (Pmode, hard_frame_pointer_rtx,
+- stack_pointer_rtx, callee_offset,
++ stack_pointer_rtx, chain_offset,
+ tmp1_rtx, tmp0_rtx, frame_pointer_needed);
+
+But the later REG_CFA_ADJUST_CFA handling still used callee_offset.
+
+I think the difference is harmless, but it's more logical for the
+CFA note to be in sync, and it's more convenient for later patches
+if it uses chain_offset.
+
+gcc/
+ * config/aarch64/aarch64.cc (aarch64_expand_prologue): Use
+ chain_offset rather than callee_offset.
+---
+ gcc/config/aarch64/aarch64.cc | 4 +---
+ 1 file changed, 1 insertion(+), 3 deletions(-)
+
+diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
+index 5d473d161d97..4f233c95140e 100644
+--- a/gcc/config/aarch64/aarch64.cc
++++ b/gcc/config/aarch64/aarch64.cc
+@@ -9985,7 +9985,6 @@ aarch64_expand_prologue (void)
+ poly_int64 initial_adjust = frame.initial_adjust;
+ HOST_WIDE_INT callee_adjust = frame.callee_adjust;
+ poly_int64 final_adjust = frame.final_adjust;
+- poly_int64 callee_offset = frame.callee_offset;
+ poly_int64 sve_callee_adjust = frame.sve_callee_adjust;
+ poly_int64 below_hard_fp_saved_regs_size
+ = frame.below_hard_fp_saved_regs_size;
+@@ -10098,8 +10097,7 @@ aarch64_expand_prologue (void)
+ implicit. */
+ if (!find_reg_note (insn, REG_CFA_ADJUST_CFA, NULL_RTX))
+ {
+- rtx src = plus_constant (Pmode, stack_pointer_rtx,
+- callee_offset);
++ rtx src = plus_constant (Pmode, stack_pointer_rtx, chain_offset);
+ add_reg_note (insn, REG_CFA_ADJUST_CFA,
+ gen_rtx_SET (hard_frame_pointer_rtx, src));
+ }
+--
+2.42.0
+