qemu/tcg-sparc-Fix-temp_allocate_frame-vs-spa.patch

From: Richard Henderson <richard.henderson@linaro.org>
Date: Fri, 18 Jun 2021 16:49:26 -0700
Subject: tcg/sparc: Fix temp_allocate_frame vs sparc stack bias
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Git-commit: 9defd1bdfb0f2ddb3ca9863e39577f3a9929d58c

We should not be aligning the offset in temp_allocate_frame,
because the odd offset produces an aligned address in the end.
Instead, pass the logical offset into tcg_set_frame and add
the stack bias last.

Cc: qemu-stable@nongnu.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Jose R. Ziviani <jziviani@suse.de>
---
 tcg/sparc/tcg-target.c.inc | 16 ++++++++++------
 tcg/tcg.c                  |  9 +++------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/tcg/sparc/tcg-target.c.inc b/tcg/sparc/tcg-target.c.inc
index 3d50f985c6cde71a5d2928db1f4f..c046d1cc6098c0a148fde7a8d7a9 100644
--- a/tcg/sparc/tcg-target.c.inc
+++ b/tcg/sparc/tcg-target.c.inc
@@ -987,14 +987,18 @@ static void tcg_target_qemu_prologue(TCGContext *s)
 {
     int tmp_buf_size, frame_size;
 
-    /* The TCG temp buffer is at the top of the frame, immediately
-       below the frame pointer.  */
+    /*
+     * The TCG temp buffer is at the top of the frame, immediately
+     * below the frame pointer.  Use the logical (aligned) offset here;
+     * the stack bias is applied in temp_allocate_frame().
+     */
     tmp_buf_size = CPU_TEMP_BUF_NLONGS * (int)sizeof(long);
-    tcg_set_frame(s, TCG_REG_I6, TCG_TARGET_STACK_BIAS - tmp_buf_size,
-                  tmp_buf_size);
+    tcg_set_frame(s, TCG_REG_I6, -tmp_buf_size, tmp_buf_size);
 
-    /* TCG_TARGET_CALL_STACK_OFFSET includes the stack bias, but is
-       otherwise the minimal frame usable by callees.  */
+    /*
+     * TCG_TARGET_CALL_STACK_OFFSET includes the stack bias, but is
+     * otherwise the minimal frame usable by callees.
+     */
     frame_size = TCG_TARGET_CALL_STACK_OFFSET - TCG_TARGET_STACK_BIAS;
     frame_size += TCG_STATIC_CALL_ARGS_SIZE + tmp_buf_size;
     frame_size += TCG_TARGET_STACK_ALIGN - 1;
diff --git a/tcg/tcg.c b/tcg/tcg.c
index 1fbe0b686d57361ed698c4ab5e5c..a9cf55531e2b9ae06d5d852cc563 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -3489,17 +3489,14 @@ static void check_regs(TCGContext *s)
 
 static void temp_allocate_frame(TCGContext *s, TCGTemp *ts)
 {
-#if !(defined(__sparc__) && TCG_TARGET_REG_BITS == 64)
-    /* Sparc64 stack is accessed with offset of 2047 */
-    s->current_frame_offset = (s->current_frame_offset +
-                               (tcg_target_long)sizeof(tcg_target_long) - 1) &
-        ~(sizeof(tcg_target_long) - 1);
-#endif
     if (s->current_frame_offset + (tcg_target_long)sizeof(tcg_target_long) >
         s->frame_end) {
         tcg_abort();
     }
     ts->mem_offset = s->current_frame_offset;
+#if defined(__sparc__)
+    ts->mem_offset += TCG_TARGET_STACK_BIAS;
+#endif
     ts->mem_base = s->frame_temp;
     ts->mem_allocated = 1;
     s->current_frame_offset += sizeof(tcg_target_long);