https://gcc.gnu.org/g:093584abb854559393e36cd4cdcf9dc4862dd046
commit r15-5731-g093584abb854559393e36cd4cdcf9dc4862dd046
Author: Uros Bizjak <ubiz...@gmail.com>
Date: Wed Nov 27 20:45:25 2024 +0100
i386: x86 can use x >> y for x >> 32+y [PR36503]
x86 targets mask 32-bit shifts with a 5-bit mask (and 64-bit with 6-bit
mask),
so they can use x >> y instead of x >> 32+y.
The optimization converts:
leal 32(%rsi), %ecx
sall %cl, %eax
to:
sall %cl, %eax
PR target/36503
gcc/ChangeLog:
* config/i386/i386.md (*ashl<mode>3_add):
New define_insn_and_split pattern.
(*ashl<mode>3_add_1): Ditto.
(*<insn><mode>3_add): Ditto.
(*<insn><mode>3_add_1): Ditto.
(*ashl<mode>3_sub): Rename from *ashl<mode>3_negcnt.
(*ashl<mode>3_sub_1): Rename from *ashl<mode>3_negcnt_1.
(*<insn><mode>3_sub): Rename from *<insn><mode>3_negcnt.
(*<insn><mode>3_sub_1): Rename from *<insn><mode>3_negcnt_1.
gcc/testsuite/ChangeLog:
* gcc.target/i386/pr36503-3.c: New test.
* gcc.target/i386/pr36503-4.c: New test.
Diff:
---
gcc/config/i386/i386.md | 100 ++++++++++++++++++++++++++++--
gcc/testsuite/gcc.target/i386/pr36503-3.c | 20 ++++++
gcc/testsuite/gcc.target/i386/pr36503-4.c | 19 ++++++
3 files changed, 135 insertions(+), 4 deletions(-)
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index df78e4df9d82..2fc48006bca7 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -15896,7 +15896,53 @@
""
[(set_attr "isa" "*,bmi2")])
-(define_insn_and_split "*ashl<mode>3_negcnt"
+(define_insn_and_split "*ashl<mode>3_add"
+ [(set (match_operand:SWI48 0 "nonimmediate_operand")
+ (ashift:SWI48
+ (match_operand:SWI48 1 "nonimmediate_operand")
+ (subreg:QI
+ (plus
+ (match_operand 2 "int248_register_operand" "c,r")
+ (match_operand 3 "const_int_operand")) 0)))
+ (clobber (reg:CC FLAGS_REG))]
+ "ix86_binary_operator_ok (ASHIFT, <MODE>mode, operands)
+ && (INTVAL (operands[3]) & (<MODE_SIZE> * BITS_PER_UNIT - 1)) == 0
+ && ix86_pre_reload_split ()"
+ "#"
+ "&& 1"
+ [(parallel
+ [(set (match_dup 0)
+ (ashift:SWI48 (match_dup 1)
+ (match_dup 2)))
+ (clobber (reg:CC FLAGS_REG))])]
+{
+ operands[2] = force_reg (GET_MODE (operands[2]), operands[2]);
+ operands[2] = gen_lowpart (QImode, operands[2]);
+}
+ [(set_attr "isa" "*,bmi2")])
+
+(define_insn_and_split "*ashl<mode>3_add_1"
+ [(set (match_operand:SWI48 0 "nonimmediate_operand")
+ (ashift:SWI48
+ (match_operand:SWI48 1 "nonimmediate_operand")
+ (plus:QI
+ (match_operand:QI 2 "register_operand" "c,r")
+ (match_operand:QI 3 "const_int_operand"))))
+ (clobber (reg:CC FLAGS_REG))]
+ "ix86_binary_operator_ok (ASHIFT, <MODE>mode, operands)
+ && (INTVAL (operands[3]) & (<MODE_SIZE> * BITS_PER_UNIT - 1)) == 0
+ && ix86_pre_reload_split ()"
+ "#"
+ "&& 1"
+ [(parallel
+ [(set (match_dup 0)
+ (ashift:SWI48 (match_dup 1)
+ (match_dup 2)))
+ (clobber (reg:CC FLAGS_REG))])]
+ ""
+ [(set_attr "isa" "*,bmi2")])
+
+(define_insn_and_split "*ashl<mode>3_sub"
[(set (match_operand:SWI48 0 "nonimmediate_operand")
(ashift:SWI48
(match_operand:SWI48 1 "nonimmediate_operand")
@@ -15927,7 +15973,7 @@
}
[(set_attr "isa" "*,bmi2")])
-(define_insn_and_split "*ashl<mode>3_negcnt_1"
+(define_insn_and_split "*ashl<mode>3_sub_1"
[(set (match_operand:SWI48 0 "nonimmediate_operand")
(ashift:SWI48
(match_operand:SWI48 1 "nonimmediate_operand")
@@ -16678,7 +16724,53 @@
""
[(set_attr "isa" "*,bmi2")])
-(define_insn_and_split "*<insn><mode>3_negcnt"
+(define_insn_and_split "*<insn><mode>3_add"
+ [(set (match_operand:SWI48 0 "nonimmediate_operand")
+ (any_shiftrt:SWI48
+ (match_operand:SWI48 1 "nonimmediate_operand")
+ (subreg:QI
+ (plus
+ (match_operand 2 "int248_register_operand" "c,r")
+ (match_operand 3 "const_int_operand")) 0)))
+ (clobber (reg:CC FLAGS_REG))]
+ "ix86_binary_operator_ok (<CODE>, <MODE>mode, operands)
+ && (INTVAL (operands[3]) & (<MODE_SIZE> * BITS_PER_UNIT - 1)) == 0
+ && ix86_pre_reload_split ()"
+ "#"
+ "&& 1"
+ [(parallel
+ [(set (match_dup 0)
+ (any_shiftrt:SWI48 (match_dup 1)
+ (match_dup 2)))
+ (clobber (reg:CC FLAGS_REG))])]
+{
+ operands[2] = force_reg (GET_MODE (operands[2]), operands[2]);
+ operands[2] = gen_lowpart (QImode, operands[2]);
+}
+ [(set_attr "isa" "*,bmi2")])
+
+(define_insn_and_split "*<insn><mode>3_add_1"
+ [(set (match_operand:SWI48 0 "nonimmediate_operand")
+ (any_shiftrt:SWI48
+ (match_operand:SWI48 1 "nonimmediate_operand")
+ (plus:QI
+ (match_operand:QI 2 "register_operand" "c,r")
+ (match_operand:QI 3 "const_int_operand"))))
+ (clobber (reg:CC FLAGS_REG))]
+ "ix86_binary_operator_ok (<CODE>, <MODE>mode, operands)
+ && (INTVAL (operands[3]) & (<MODE_SIZE> * BITS_PER_UNIT - 1)) == 0
+ && ix86_pre_reload_split ()"
+ "#"
+ "&& 1"
+ [(parallel
+ [(set (match_dup 0)
+ (any_shiftrt:SWI48 (match_dup 1)
+ (match_dup 2)))
+ (clobber (reg:CC FLAGS_REG))])]
+ ""
+ [(set_attr "isa" "*,bmi2")])
+
+(define_insn_and_split "*<insn><mode>3_sub"
[(set (match_operand:SWI48 0 "nonimmediate_operand")
(any_shiftrt:SWI48
(match_operand:SWI48 1 "nonimmediate_operand")
@@ -16709,7 +16801,7 @@
}
[(set_attr "isa" "*,bmi2")])
-(define_insn_and_split "*<insn><mode>3_negcnt_1"
+(define_insn_and_split "*<insn><mode>3_sub_1"
[(set (match_operand:SWI48 0 "nonimmediate_operand")
(any_shiftrt:SWI48
(match_operand:SWI48 1 "nonimmediate_operand")
diff --git a/gcc/testsuite/gcc.target/i386/pr36503-3.c
b/gcc/testsuite/gcc.target/i386/pr36503-3.c
new file mode 100644
index 000000000000..6ac4f416c1b0
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr36503-3.c
@@ -0,0 +1,20 @@
+/* PR target/36503 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -masm=att" } */
+/* { dg-additional-options "-mregparm=3" { target ia32 } } */
+/* { dg-final { scan-assembler-not "leal\[ \\t\]+32" } } */
+
+int foo (int i, int n)
+{
+ return i << (32 + n);
+}
+
+int bar (int i, int n)
+{
+ return i >> (32 + n);
+}
+
+unsigned int baz (unsigned int i, int n)
+{
+ return i >> (32 + n);
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr36503-4.c
b/gcc/testsuite/gcc.target/i386/pr36503-4.c
new file mode 100644
index 000000000000..1fd81f26f591
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr36503-4.c
@@ -0,0 +1,19 @@
+/* PR target/36503 */
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-O2 -masm=att" } */
+/* { dg-final { scan-assembler-not "leal\[ \\t\]+64" } } */
+
+long long foo (long long i, int n)
+{
+ return i << (64 + n);
+}
+
+long long bar (long long i, int n)
+{
+ return i >> (64 + n);
+}
+
+unsigned long long baz (unsigned long long i, int n)
+{
+ return i >> (64 + n);
+}
