Before optimization, the operation of taking fixed-point numbers from memory
and then forcing type conversion needs to be loaded into fixed-point registers
before conversion. After the optimization is completed, the fixed-point value
is directly transferred to the floating-point register for type conversion.
eg:
extern int a;
float
test(void)
{
return (float)a;
}
Assembly code before optimization:
pcalau12i $r12,%got_pc_hi20(a)
ld.d $r12,$r12,%got_pc_lo12(a)
ldptr.w $r12,$r12,0
movgr2fr.w $f0,$r12
ffint.s.w $f0,$f0
Optimized assembly code:
pcalau12i $r12,%got_pc_hi20(a)
ld.d $r12,$r12,%got_pc_lo12(a)
fld.s $f0,$r12,0
ffint.s.w $f0,$f0
gcc/ChangeLog:
* config/loongarch/loongarch.md: Allows fixed-point values to be loaded
from memory into floating-point registers.
gcc/testsuite/ChangeLog:
* gcc.target/loongarch/float-load.c: New test.
---
gcc/config/loongarch/loongarch.md | 4 ++--
gcc/testsuite/gcc.target/loongarch/float-load.c | 11 +++++++++++
2 files changed, 13 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/loongarch/float-load.c
diff --git a/gcc/config/loongarch/loongarch.md
b/gcc/config/loongarch/loongarch.md
index a6fb2b935fa..eb580697915 100644
--- a/gcc/config/loongarch/loongarch.md
+++ b/gcc/config/loongarch/loongarch.md
@@ -1828,8 +1828,8 @@ (define_expand "movsi"
})
(define_insn_and_split "*movsi_internal"
- [(set (match_operand:SI 0 "nonimmediate_operand"
"=r,r,r,w,*f,*f,*r,*m,*r,*z")
- (match_operand:SI 1 "move_operand" "r,Yd,w,rJ,*r*J,*m,*f,*f,*z,*r"))]
+ [(set (match_operand:SI 0 "nonimmediate_operand" "=r,r,r,w,*f,f,*r,*m,*r,*z")
+ (match_operand:SI 1 "move_operand" "r,Yd,w,rJ,*r*J,m,*f,*f,*z,*r"))]
"(register_operand (operands[0], SImode)
|| reg_or_0_operand (operands[1], SImode))"
{ return loongarch_output_move (operands[0], operands[1]); }
diff --git a/gcc/testsuite/gcc.target/loongarch/float-load.c
b/gcc/testsuite/gcc.target/loongarch/float-load.c
new file mode 100644
index 00000000000..c757a795e21
--- /dev/null
+++ b/gcc/testsuite/gcc.target/loongarch/float-load.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+/* { dg-final { scan-assembler "fld\\.s" } } */
+
+extern int a;
+float
+test (void)
+{
+ return (float)a;
+}
+
--
2.31.1
