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-rw-r--r--packages/gcc/13.2.0/0028-aarch64-Put-LR-save-probe-in-first-16-bytes.patch406
1 files changed, 0 insertions, 406 deletions
diff --git a/packages/gcc/13.2.0/0028-aarch64-Put-LR-save-probe-in-first-16-bytes.patch b/packages/gcc/13.2.0/0028-aarch64-Put-LR-save-probe-in-first-16-bytes.patch
deleted file mode 100644
index 4ba2df93..00000000
--- a/packages/gcc/13.2.0/0028-aarch64-Put-LR-save-probe-in-first-16-bytes.patch
+++ /dev/null
@@ -1,406 +0,0 @@
-From 8433953434a7b58c0923140d39eb3c5988c1d097 Mon Sep 17 00:00:00 2001
-From: Richard Sandiford <richard.sandiford@arm.com>
-Date: Tue, 12 Sep 2023 16:07:19 +0100
-Subject: [PATCH 28/32] aarch64: Put LR save probe in first 16 bytes
-
--fstack-clash-protection uses the save of LR as a probe for the next
-allocation. The next allocation could be:
-
-* another part of the static frame, e.g. when allocating SVE save slots
- or outgoing arguments
-
-* an alloca in the same function
-
-* an allocation made by a callee function
-
-However, when -fomit-frame-pointer is used, the LR save slot is placed
-above the other GPR save slots. It could therefore be up to 80 bytes
-above the base of the GPR save area (which is also the hard fp address).
-
-aarch64_allocate_and_probe_stack_space took this into account when
-deciding how much subsequent space could be allocated without needing
-a probe. However, it interacted badly with:
-
- /* If doing a small final adjustment, we always probe at offset 0.
- This is done to avoid issues when LR is not at position 0 or when
- the final adjustment is smaller than the probing offset. */
- else if (final_adjustment_p && rounded_size == 0)
- residual_probe_offset = 0;
-
-which forces any allocation that is smaller than the guard page size
-to be probed at offset 0 rather than the usual offset 1024. It was
-therefore possible to construct cases in which we had:
-
-* a probe using LR at SP + 80 bytes (or some other value >= 16)
-* an allocation of the guard page size - 16 bytes
-* a probe at SP + 0
-
-which allocates guard page size + 64 consecutive unprobed bytes.
-
-This patch requires the LR probe to be in the first 16 bytes of the
-save area when stack clash protection is active. Doing it
-unconditionally would cause code-quality regressions.
-
-Putting LR before other registers prevents push/pop allocation
-when shadow call stacks are enabled, since LR is restored
-separately from the other callee-saved registers.
-
-The new comment doesn't say that the probe register is required
-to be LR, since a later patch removes that restriction.
-
-gcc/
- * config/aarch64/aarch64.cc (aarch64_layout_frame): Ensure that
- the LR save slot is in the first 16 bytes of the register save area.
- Only form STP/LDP push/pop candidates if both registers are valid.
- (aarch64_allocate_and_probe_stack_space): Remove workaround for
- when LR was not in the first 16 bytes.
-
-gcc/testsuite/
- * gcc.target/aarch64/stack-check-prologue-18.c: New test.
- * gcc.target/aarch64/stack-check-prologue-19.c: Likewise.
- * gcc.target/aarch64/stack-check-prologue-20.c: Likewise.
----
- gcc/config/aarch64/aarch64.cc | 72 ++++++-------
- .../aarch64/stack-check-prologue-18.c | 100 ++++++++++++++++++
- .../aarch64/stack-check-prologue-19.c | 100 ++++++++++++++++++
- .../aarch64/stack-check-prologue-20.c | 3 +
- 4 files changed, 233 insertions(+), 42 deletions(-)
- create mode 100644 gcc/testsuite/gcc.target/aarch64/stack-check-prologue-18.c
- create mode 100644 gcc/testsuite/gcc.target/aarch64/stack-check-prologue-19.c
- create mode 100644 gcc/testsuite/gcc.target/aarch64/stack-check-prologue-20.c
-
-diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
-index 5cad847977a4..a765f92329d3 100644
---- a/gcc/config/aarch64/aarch64.cc
-+++ b/gcc/config/aarch64/aarch64.cc
-@@ -8534,26 +8534,34 @@ aarch64_layout_frame (void)
- bool saves_below_hard_fp_p
- = maybe_ne (frame.below_hard_fp_saved_regs_size, 0);
- frame.bytes_below_hard_fp = offset;
-+
-+ auto allocate_gpr_slot = [&](unsigned int regno)
-+ {
-+ frame.reg_offset[regno] = offset;
-+ if (frame.wb_push_candidate1 == INVALID_REGNUM)
-+ frame.wb_push_candidate1 = regno;
-+ else if (frame.wb_push_candidate2 == INVALID_REGNUM)
-+ frame.wb_push_candidate2 = regno;
-+ offset += UNITS_PER_WORD;
-+ };
-+
- if (frame.emit_frame_chain)
- {
- /* FP and LR are placed in the linkage record. */
-- frame.reg_offset[R29_REGNUM] = offset;
-- frame.wb_push_candidate1 = R29_REGNUM;
-- frame.reg_offset[R30_REGNUM] = offset + UNITS_PER_WORD;
-- frame.wb_push_candidate2 = R30_REGNUM;
-- offset += 2 * UNITS_PER_WORD;
-+ allocate_gpr_slot (R29_REGNUM);
-+ allocate_gpr_slot (R30_REGNUM);
- }
-+ else if (flag_stack_clash_protection
-+ && known_eq (frame.reg_offset[R30_REGNUM], SLOT_REQUIRED))
-+ /* Put the LR save slot first, since it makes a good choice of probe
-+ for stack clash purposes. The idea is that the link register usually
-+ has to be saved before a call anyway, and so we lose little by
-+ stopping it from being individually shrink-wrapped. */
-+ allocate_gpr_slot (R30_REGNUM);
-
- for (regno = R0_REGNUM; regno <= R30_REGNUM; regno++)
- if (known_eq (frame.reg_offset[regno], SLOT_REQUIRED))
-- {
-- frame.reg_offset[regno] = offset;
-- if (frame.wb_push_candidate1 == INVALID_REGNUM)
-- frame.wb_push_candidate1 = regno;
-- else if (frame.wb_push_candidate2 == INVALID_REGNUM)
-- frame.wb_push_candidate2 = regno;
-- offset += UNITS_PER_WORD;
-- }
-+ allocate_gpr_slot (regno);
-
- poly_int64 max_int_offset = offset;
- offset = aligned_upper_bound (offset, STACK_BOUNDARY / BITS_PER_UNIT);
-@@ -8631,10 +8639,13 @@ aarch64_layout_frame (void)
- max_push_offset to 0, because no registers are popped at this time,
- so callee_adjust cannot be adjusted. */
- HOST_WIDE_INT max_push_offset = 0;
-- if (frame.wb_pop_candidate2 != INVALID_REGNUM)
-- max_push_offset = 512;
-- else if (frame.wb_pop_candidate1 != INVALID_REGNUM)
-- max_push_offset = 256;
-+ if (frame.wb_pop_candidate1 != INVALID_REGNUM)
-+ {
-+ if (frame.wb_pop_candidate2 != INVALID_REGNUM)
-+ max_push_offset = 512;
-+ else
-+ max_push_offset = 256;
-+ }
-
- HOST_WIDE_INT const_size, const_below_saved_regs, const_above_fp;
- HOST_WIDE_INT const_saved_regs_size;
-@@ -9654,29 +9665,6 @@ aarch64_allocate_and_probe_stack_space (rtx temp1, rtx temp2,
- = (final_adjustment_p
- ? guard_used_by_caller + byte_sp_alignment
- : guard_size - guard_used_by_caller);
-- /* When doing the final adjustment for the outgoing arguments, take into
-- account any unprobed space there is above the current SP. There are
-- two cases:
--
-- - When saving SVE registers below the hard frame pointer, we force
-- the lowest save to take place in the prologue before doing the final
-- adjustment (i.e. we don't allow the save to be shrink-wrapped).
-- This acts as a probe at SP, so there is no unprobed space.
--
-- - When there are no SVE register saves, we use the store of the link
-- register as a probe. We can't assume that LR was saved at position 0
-- though, so treat any space below it as unprobed. */
-- if (final_adjustment_p
-- && known_eq (frame.below_hard_fp_saved_regs_size, 0))
-- {
-- poly_int64 lr_offset = (frame.reg_offset[LR_REGNUM]
-- - frame.bytes_below_saved_regs);
-- if (known_ge (lr_offset, 0))
-- min_probe_threshold -= lr_offset.to_constant ();
-- else
-- gcc_assert (!flag_stack_clash_protection || known_eq (poly_size, 0));
-- }
--
- poly_int64 frame_size = frame.frame_size;
-
- /* We should always have a positive probe threshold. */
-@@ -9856,8 +9844,8 @@ aarch64_allocate_and_probe_stack_space (rtx temp1, rtx temp2,
- if (final_adjustment_p && rounded_size != 0)
- min_probe_threshold = 0;
- /* If doing a small final adjustment, we always probe at offset 0.
-- This is done to avoid issues when LR is not at position 0 or when
-- the final adjustment is smaller than the probing offset. */
-+ This is done to avoid issues when the final adjustment is smaller
-+ than the probing offset. */
- else if (final_adjustment_p && rounded_size == 0)
- residual_probe_offset = 0;
-
-diff --git a/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-18.c b/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-18.c
-new file mode 100644
-index 000000000000..82447d20fff5
---- /dev/null
-+++ b/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-18.c
-@@ -0,0 +1,100 @@
-+/* { dg-options "-O2 -fstack-clash-protection -fomit-frame-pointer --param stack-clash-protection-guard-size=12" } */
-+/* { dg-final { check-function-bodies "**" "" } } */
-+
-+void f(int, ...);
-+void g();
-+
-+/*
-+** test1:
-+** ...
-+** str x30, \[sp\]
-+** sub sp, sp, #4064
-+** str xzr, \[sp\]
-+** cbnz w0, .*
-+** bl g
-+** ...
-+** str x26, \[sp, #?4128\]
-+** ...
-+*/
-+int test1(int z) {
-+ __uint128_t x = 0;
-+ int y[0x400];
-+ if (z)
-+ {
-+ asm volatile ("" :::
-+ "x19", "x20", "x21", "x22", "x23", "x24", "x25", "x26");
-+ f(0, 0, 0, 0, 0, 0, 0, &y,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x);
-+ }
-+ g();
-+ return 1;
-+}
-+
-+/*
-+** test2:
-+** ...
-+** str x30, \[sp\]
-+** sub sp, sp, #1040
-+** str xzr, \[sp\]
-+** cbnz w0, .*
-+** bl g
-+** ...
-+*/
-+int test2(int z) {
-+ __uint128_t x = 0;
-+ int y[0x400];
-+ if (z)
-+ {
-+ asm volatile ("" :::
-+ "x19", "x20", "x21", "x22", "x23", "x24", "x25", "x26");
-+ f(0, 0, 0, 0, 0, 0, 0, &y,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x);
-+ }
-+ g();
-+ return 1;
-+}
-+
-+/*
-+** test3:
-+** ...
-+** str x30, \[sp\]
-+** sub sp, sp, #1024
-+** cbnz w0, .*
-+** bl g
-+** ...
-+*/
-+int test3(int z) {
-+ __uint128_t x = 0;
-+ int y[0x400];
-+ if (z)
-+ {
-+ asm volatile ("" :::
-+ "x19", "x20", "x21", "x22", "x23", "x24", "x25", "x26");
-+ f(0, 0, 0, 0, 0, 0, 0, &y,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x);
-+ }
-+ g();
-+ return 1;
-+}
-diff --git a/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-19.c b/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-19.c
-new file mode 100644
-index 000000000000..73ac3e4e4eb0
---- /dev/null
-+++ b/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-19.c
-@@ -0,0 +1,100 @@
-+/* { dg-options "-O2 -fstack-clash-protection -fomit-frame-pointer --param stack-clash-protection-guard-size=12 -fsanitize=shadow-call-stack -ffixed-x18" } */
-+/* { dg-final { check-function-bodies "**" "" } } */
-+
-+void f(int, ...);
-+void g();
-+
-+/*
-+** test1:
-+** ...
-+** str x30, \[sp\]
-+** sub sp, sp, #4064
-+** str xzr, \[sp\]
-+** cbnz w0, .*
-+** bl g
-+** ...
-+** str x26, \[sp, #?4128\]
-+** ...
-+*/
-+int test1(int z) {
-+ __uint128_t x = 0;
-+ int y[0x400];
-+ if (z)
-+ {
-+ asm volatile ("" :::
-+ "x19", "x20", "x21", "x22", "x23", "x24", "x25", "x26");
-+ f(0, 0, 0, 0, 0, 0, 0, &y,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x);
-+ }
-+ g();
-+ return 1;
-+}
-+
-+/*
-+** test2:
-+** ...
-+** str x30, \[sp\]
-+** sub sp, sp, #1040
-+** str xzr, \[sp\]
-+** cbnz w0, .*
-+** bl g
-+** ...
-+*/
-+int test2(int z) {
-+ __uint128_t x = 0;
-+ int y[0x400];
-+ if (z)
-+ {
-+ asm volatile ("" :::
-+ "x19", "x20", "x21", "x22", "x23", "x24", "x25", "x26");
-+ f(0, 0, 0, 0, 0, 0, 0, &y,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x);
-+ }
-+ g();
-+ return 1;
-+}
-+
-+/*
-+** test3:
-+** ...
-+** str x30, \[sp\]
-+** sub sp, sp, #1024
-+** cbnz w0, .*
-+** bl g
-+** ...
-+*/
-+int test3(int z) {
-+ __uint128_t x = 0;
-+ int y[0x400];
-+ if (z)
-+ {
-+ asm volatile ("" :::
-+ "x19", "x20", "x21", "x22", "x23", "x24", "x25", "x26");
-+ f(0, 0, 0, 0, 0, 0, 0, &y,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x,
-+ x, x, x, x, x, x, x, x, x, x, x, x, x, x, x, x);
-+ }
-+ g();
-+ return 1;
-+}
-diff --git a/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-20.c b/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-20.c
-new file mode 100644
-index 000000000000..690aae8dfd5b
---- /dev/null
-+++ b/gcc/testsuite/gcc.target/aarch64/stack-check-prologue-20.c
-@@ -0,0 +1,3 @@
-+/* { dg-options "-O2 -fstack-protector-all -fstack-clash-protection -fomit-frame-pointer --param stack-clash-protection-guard-size=12 -fsanitize=shadow-call-stack -ffixed-x18" } */
-+
-+#include "stack-check-prologue-19.c"
---
-2.42.0
-
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-08 14:57:06 +0000