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From: Peter Maydell <peter.maydell@linaro.org>
To: qemu-arm@nongnu.org, qemu-devel@nongnu.org
Cc: patches@linaro.org, Richard Henderson <rth@twiddle.net>
Subject: [Qemu-devel] [PATCH 5/7] arm: Move condition-failed codepath generation out of if()
Date: Mon, 10 Apr 2017 11:39:51 +0100	[thread overview]
Message-ID: <1491820793-5348-6-git-send-email-peter.maydell@linaro.org> (raw)
In-Reply-To: <1491820793-5348-1-git-send-email-peter.maydell@linaro.org>

Move the code to generate the "condition failed" instruction
codepath out of the if (singlestepping) {} else {}. This
will allow adding support for handling a new is_jmp type
which can't be neatly split into "singlestepping case"
versus "not singlestepping case".

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/translate.c | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/target/arm/translate.c b/target/arm/translate.c
index a1a0e73..87fd702 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -11988,9 +11988,9 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
     /* At this stage dc->condjmp will only be set when the skipped
        instruction was a conditional branch or trap, and the PC has
        already been written.  */
+    gen_set_condexec(dc);
     if (unlikely(cs->singlestep_enabled || dc->ss_active)) {
         /* Unconditional and "condition passed" instruction codepath. */
-        gen_set_condexec(dc);
         switch (dc->is_jmp) {
         case DISAS_SWI:
             gen_ss_advance(dc);
@@ -12013,13 +12013,6 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
             /* FIXME: Single stepping a WFI insn will not halt the CPU. */
             gen_singlestep_exception(dc);
         }
-        if (dc->condjmp) {
-            /* "Condition failed" instruction codepath. */
-            gen_set_label(dc->condlabel);
-            gen_set_condexec(dc);
-            gen_set_pc_im(dc, dc->pc);
-            gen_singlestep_exception(dc);
-        }
     } else {
         /* While branches must always occur at the end of an IT block,
            there are a few other things that can cause us to terminate
@@ -12029,7 +12022,6 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
             - Hardware watchpoints.
            Hardware breakpoints have already been handled and skip this code.
          */
-        gen_set_condexec(dc);
         switch(dc->is_jmp) {
         case DISAS_NEXT:
             gen_goto_tb(dc, 1, dc->pc);
@@ -12069,11 +12061,17 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
             gen_exception(EXCP_SMC, syn_aa32_smc(), 3);
             break;
         }
-        if (dc->condjmp) {
-            gen_set_label(dc->condlabel);
-            gen_set_condexec(dc);
+    }
+
+    if (dc->condjmp) {
+        /* "Condition failed" instruction codepath for the branch/trap insn */
+        gen_set_label(dc->condlabel);
+        gen_set_condexec(dc);
+        if (unlikely(cs->singlestep_enabled || dc->ss_active)) {
+            gen_set_pc_im(dc, dc->pc);
+            gen_singlestep_exception(dc);
+        } else {
             gen_goto_tb(dc, 1, dc->pc);
-            dc->condjmp = 0;
         }
     }
 
-- 
2.7.4

  parent reply	other threads:[~2017-04-10 10:45 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-10 10:39 [Qemu-devel] [PATCH 0/7] arm: Implement M profile exception return properly Peter Maydell
2017-04-10 10:39 ` [Qemu-devel] [PATCH 1/7] arm: Don't implement BXJ on M-profile CPUs Peter Maydell
2017-04-10 11:43   ` [Qemu-devel] [Qemu-arm] " Philippe Mathieu-Daudé
2017-04-10 10:39 ` [Qemu-devel] [PATCH 2/7] arm: Thumb shift operations should not permit interworking branches Peter Maydell
2017-04-10 10:39 ` [Qemu-devel] [PATCH 3/7] arm: Factor out "generate right kind of step exception" Peter Maydell
2017-04-10 11:43   ` [Qemu-devel] [Qemu-arm] " Philippe Mathieu-Daudé
2017-04-10 10:39 ` [Qemu-devel] [PATCH 4/7] arm: Move gen_set_condexec() and gen_set_pc_im() up in the file Peter Maydell
2017-04-10 11:44   ` [Qemu-devel] [Qemu-arm] " Philippe Mathieu-Daudé
2017-04-10 10:39 ` Peter Maydell [this message]
2017-04-10 13:22   ` [Qemu-devel] [Qemu-arm] [PATCH 5/7] arm: Move condition-failed codepath generation out of if() Philippe Mathieu-Daudé
2017-04-10 16:45     ` Peter Maydell
2017-04-10 10:39 ` [Qemu-devel] [PATCH 6/7] arm: Implement M profile exception return properly Peter Maydell
2017-04-10 13:52   ` [Qemu-devel] [Qemu-arm] " Philippe Mathieu-Daudé
2017-04-10 13:54     ` Peter Maydell
2017-04-10 16:28   ` Peter Maydell
2017-04-10 10:39 ` [Qemu-devel] [PATCH 7/7] arm: Remove workarounds for old M-profile exception return implementation Peter Maydell
2017-04-10 13:53   ` [Qemu-devel] [Qemu-arm] " Philippe Mathieu-Daudé

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