diff mbox

[SH,committed] Fix PR 69806

Message ID 1456148220.14977.11.camel@t-online.de
State New
Headers show

Commit Message

Oleg Endo Feb. 22, 2016, 1:37 p.m. UTC
Hi,

The attached patch fixes PR 69806.

Tested on sh-elf with
make -k check RUNTESTFLAGS="--target_board=sh-sim\{-m2/-ml,-m2/-mb,
-m2a/-mb,-m4/-ml,-m4/-mb,-m4a/-ml,-m4a/-mb}"

Committed as r233601.

Cheers,
Oleg

gcc/ChangeLog
	PR target/69806
	PR target/54089
	* config/sh/sh.c (sh_lshrsi_clobbers_t_reg_p, sh_dynamicalize_shift_p):
	Handle negative shift counts.
	* config/sh/sh.md (ashlsi3, lshrsi3_n, lshrsi3_n_clobbers_t): Don't use
	force_reg on the shift constant.
	(lshrsi3): Likewise.  Expand into lshrsi3_n* instead of lshrsi3_d.
	(lshrsi3_d): Handle negative shift counts.

gcc/testsuite/ChangeLog
	PR target/69806
	PR target/54089
	* gcc.target/sh/pr54089-10.c: New.
diff mbox

Patch

Index: gcc/config/sh/sh.c
===================================================================
--- gcc/config/sh/sh.c	(revision 233581)
+++ gcc/config/sh/sh.c	(working copy)
@@ -3259,7 +3259,8 @@ 
 {
   gcc_assert (CONST_INT_P (shift_amount));
 
-  const int shift_amount_i = INTVAL (shift_amount) & 31;
+  /* For right shifts the constant might be negative.  */
+  const int shift_amount_i = std::abs (INTVAL (shift_amount)) & 31;
  
   /* Special case for shift count of 31: use shll-movt sequence.  */
   if (shift_amount_i == 31)
@@ -3278,7 +3279,8 @@ 
 {
   gcc_assert (CONST_INT_P (count));
 
-  const int shift_amount_i = INTVAL (count) & 31;
+  /* For right shifts the constant might be negative.  */
+  const int shift_amount_i = std::abs (INTVAL (count)) & 31;
   int insn_count;
 
   /* For left and right shifts, there are shorter 2 insn sequences for
Index: gcc/config/sh/sh.md
===================================================================
--- gcc/config/sh/sh.md	(revision 233581)
+++ gcc/config/sh/sh.md	(working copy)
@@ -5011,7 +5011,10 @@ 
     }
   if (TARGET_DYNSHIFT
       && CONST_INT_P (operands[2]) && sh_dynamicalize_shift_p (operands[2]))
-      operands[2] = force_reg (SImode, operands[2]);
+    {
+      /* Don't force the constant into a reg yet.  Some other optimizations
+	 might not see through the reg that holds the shift count.  */
+    }
 
   /*  If the ashlsi3_* insn is going to clobber the T_REG it must be
       expanded here.  */
@@ -5567,9 +5570,12 @@ 
   if (TARGET_DYNSHIFT
       && CONST_INT_P (operands[2]) && sh_dynamicalize_shift_p (operands[2]))
     {
-      rtx neg_count = force_reg (SImode,
-			         gen_int_mode (- INTVAL (operands[2]), SImode));
-      emit_insn (gen_lshrsi3_d (operands[0], operands[1], neg_count));
+      /* Don't force the constant into a reg yet.  Some other optimizations
+	 might not see through the reg that holds the shift count.  */
+      if (sh_lshrsi_clobbers_t_reg_p (operands[2]))
+        emit_insn (gen_lshrsi3_n_clobbers_t (operands[0], operands[1], operands[2]));
+      else
+        emit_insn (gen_lshrsi3_n (operands[0], operands[1], operands[2]));
       DONE;
     }
 
@@ -5621,6 +5627,10 @@ 
    && ! sh_lshrsi_clobbers_t_reg_p (operands[2])"
   [(const_int 0)]
 {
+  /* The shift count const_int is a negative value for all dynamic
+     right shift insns.  */
+  operands[2] = GEN_INT (- INTVAL (operands[2]));
+
   if (satisfies_constraint_P27 (operands[2]))
     {
       /* This will not be done for a shift amount of 1, because it would
@@ -5679,8 +5689,7 @@ 
     {
       /* If this pattern was picked and dynamic shifts are supported, switch
 	 to dynamic shift pattern before reload.  */
-      operands[2] = force_reg (SImode,
-			       gen_int_mode (- INTVAL (operands[2]), SImode));
+      operands[2] = GEN_INT (- INTVAL (operands[2]));
       emit_insn (gen_lshrsi3_d (operands[0], operands[1], operands[2]));
     }
   else
@@ -5711,8 +5720,7 @@ 
     {
       /* If this pattern was picked and dynamic shifts are supported, switch
 	 to dynamic shift pattern before reload.  */
-      operands[2] = force_reg (SImode,
-			       gen_int_mode (- INTVAL (operands[2]), SImode));
+      operands[2] = GEN_INT (- INTVAL (operands[2]));
       emit_insn (gen_lshrsi3_d (operands[0], operands[1], operands[2]));
     }
   else
Index: gcc/testsuite/gcc.target/sh/pr54089-10.c
===================================================================
--- gcc/testsuite/gcc.target/sh/pr54089-10.c	(revision 0)
+++ gcc/testsuite/gcc.target/sh/pr54089-10.c	(working copy)
@@ -0,0 +1,153 @@ 
+/* Check that there are no redundant zero extensions around logical right
+   shifts.  */
+/* { dg-do compile }  */
+/* { dg-options "-O1" }  */
+/* { dg-final { scan-assembler-times "extu" 20 } }  */
+
+/* { dg-final { scan-assembler-times "shll" 2 { target { "! sh2a" && has_dyn_shift } } } }  */
+/* { dg-final { scan-assembler-times "shll" 3 { target { "! sh2a" && "! has_dyn_shift" } } } }  */
+/* { dg-final { scan-assembler-times "movt" 2 { target { ! sh2a } } } }  */
+
+/* { dg-final { scan-assembler-times "bld" 1 { target { sh2a } } } }  */
+/* { dg-final { scan-assembler-times "movt" 1 { target { sh2a } } } }  */
+/* { dg-final { scan-assembler-times "movrt" 1 { target { sh2a } } } }  */
+/* { dg-final { scan-assembler-times "cmp/pz" 1 { target { sh2a } } } }  */
+
+/* { dg-final { scan-assembler-times "shld" 9 { target { has_dyn_shift } } } }  */
+
+void
+test_0 (unsigned char* x, unsigned int* y)
+{
+  y[0] = x[1] >> 1;
+}
+
+void
+test_1 (unsigned char* x, unsigned int* y)
+{
+  y[0] = x[1] >> 2;
+}
+
+void
+test_2 (unsigned char* x, unsigned int* y)
+{
+  y[0] = x[1] >> 3;
+}
+
+void
+test_3 (unsigned char* x, unsigned int* y)
+{
+  y[0] = x[1] >> 4;
+}
+
+void
+test_4 (unsigned char* x, unsigned int* y)
+{
+  y[0] = x[1] >> 5;
+}
+
+void
+test_5 (unsigned char* x, unsigned int* y)
+{
+  y[0] = x[1] >> 6;
+}
+
+void
+test_6 (unsigned char* x, unsigned int* y)
+{
+  /* non-SH2A: shll, movt
+     SH2A: bld, movt */
+  y[0] = x[1] >> 7;
+}
+
+
+void
+test_100 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 1;
+}
+
+void
+test_101 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 2;
+}
+
+void
+test_102 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 3;
+}
+
+void
+test_103 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 4;
+}
+
+void
+test_104 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 5;
+}
+
+void
+test_105 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 6;
+}
+
+void
+test_106 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 7;
+}
+
+void
+test_107 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 8;
+}
+
+void
+test_108 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 9;
+}
+
+void
+test_109 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 10;
+}
+
+void
+test_110 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 11;
+}
+
+void
+test_111 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 12;
+}
+
+void
+test_112 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 13;
+}
+
+void
+test_113 (unsigned short* x, unsigned int* y)
+{
+  y[0] = x[1] >> 14;
+}
+
+void
+test_114 (unsigned short* x, unsigned int* y)
+{
+  /* non-SH2A: shll, movt
+     SH2A: cmp/pz, movrt */
+  y[0] = x[1] >> 15;
+}