aboutsummaryrefslogtreecommitdiff
path: root/gcc
diff options
context:
space:
mode:
authorSegher Boessenkool <segher@kernel.crashing.org>2017-02-17 16:00:37 +0100
committerSegher Boessenkool <segher@gcc.gnu.org>2017-02-17 16:00:37 +0100
commit4bcd6597a33c86615059873504b3140f49c3b96c (patch)
treec24026ef6a29900599fb94c54cebfb9bcba423b2 /gcc
parent3185712c775f226df6f06304a1d7e0e87a1b99c3 (diff)
downloadgcc-4bcd6597a33c86615059873504b3140f49c3b96c.zip
gcc-4bcd6597a33c86615059873504b3140f49c3b96c.tar.gz
gcc-4bcd6597a33c86615059873504b3140f49c3b96c.tar.bz2
rs6000: Fix extendsfdf2 for signaling NaNs
A cast from float to double should turn a signaling NaN into a quiet NaN, if using -fsignaling-nans. On PowerPC single-precision floats are stored as double precision in registers, and so, the cast normally does nothing. This causes gcc.dg/pr59833.c to fail (it does such a cast, and expects a quiet NaN as output). This patch adds a new pattern, used with -fsignaling-nans in effect, that creates an frsp instruction (or xsrsp) in this case. Since the input already is SFmode, that instruction turns signaling NaNs into quiet NaNs and does nothing more. * config/rs6000/rs6000.md (extendsfdf2): Remove default arguments. If HONOR_SNANS (SFmode) force the input to a register. (*extendsfdf2_fpr): Add !HONOR_SNANS (SFmode) condition. (*extendsfdf2_snan): New pattern, used when using SNaNs; it generates an frsp or similar insn. From-SVN: r245534
Diffstat (limited to 'gcc')
-rw-r--r--gcc/ChangeLog8
-rw-r--r--gcc/config/rs6000/rs6000.md22
2 files changed, 26 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2960c7d..0339ac9 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2017-02-17 Segher Boessenkool <segher@kernel.crashing.org>
+
+ * config/rs6000/rs6000.md (extendsfdf2): Remove default arguments.
+ If HONOR_SNANS (SFmode) force the input to a register.
+ (*extendsfdf2_fpr): Add !HONOR_SNANS (SFmode) condition.
+ (*extendsfdf2_snan): New pattern, used when using SNaNs; it generates
+ an frsp or similar insn.
+
2017-02-17 Martin Liska <mliska@suse.cz>
PR rtl-optimization/79577
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index fca6de0..58e63c1 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -4648,15 +4648,19 @@
;; Floating point conversions
(define_expand "extendsfdf2"
- [(set (match_operand:DF 0 "gpc_reg_operand" "")
- (float_extend:DF (match_operand:SF 1 "reg_or_none500mem_operand" "")))]
+ [(set (match_operand:DF 0 "gpc_reg_operand")
+ (float_extend:DF (match_operand:SF 1 "reg_or_none500mem_operand")))]
"TARGET_HARD_FLOAT && ((TARGET_FPRS && TARGET_DOUBLE_FLOAT) || TARGET_E500_DOUBLE)"
- "")
+{
+ if (HONOR_SNANS (SFmode))
+ operands[1] = force_reg (SFmode, operands[1]);
+})
(define_insn_and_split "*extendsfdf2_fpr"
[(set (match_operand:DF 0 "gpc_reg_operand" "=d,?d,d,ws,?ws,wu,wb")
(float_extend:DF (match_operand:SF 1 "reg_or_mem_operand" "0,f,m,0,wy,Z,wY")))]
- "TARGET_HARD_FLOAT && TARGET_FPRS && TARGET_DOUBLE_FLOAT"
+ "TARGET_HARD_FLOAT && TARGET_FPRS && TARGET_DOUBLE_FLOAT
+ && !HONOR_SNANS (SFmode)"
"@
#
fmr %0,%1
@@ -4673,6 +4677,16 @@
}
[(set_attr "type" "fp,fpsimple,fpload,fp,fpsimple,fpload,fpload")])
+(define_insn "*extendsfdf2_snan"
+ [(set (match_operand:DF 0 "gpc_reg_operand" "=d,ws")
+ (float_extend:DF (match_operand:SF 1 "gpc_reg_operand" "f,wy")))]
+ "TARGET_HARD_FLOAT && TARGET_FPRS && TARGET_DOUBLE_FLOAT
+ && HONOR_SNANS (SFmode)"
+ "@
+ frsp %0,%1
+ xsrsp %x0,%x1"
+ [(set_attr "type" "fp")])
+
(define_expand "truncdfsf2"
[(set (match_operand:SF 0 "gpc_reg_operand" "")
(float_truncate:SF (match_operand:DF 1 "gpc_reg_operand" "")))]